Unit 2 Study Guides

Question 1

What are the three main functions of the lymphatic system? What is a lacteal?

Answer 1

1) Fluid recovery, immunity, and lipid absorption
2) Lacteals are lymphatic vessels in the small intestine that absorb dietary lipids that are not absorbed by the blood capillaries

Question 2

What 4 structures make up the lymphatic system? How much fluid enters the lymphatic system?

Answer 2

1) Lymph, lymphatic vessels, lymphatic tissues, and lymphatic organs
2) 15% (~3 L/day) of fluid enters the lymphatic system

Question 3

How does lymph form and what’s it color? What fluid is lymph most similar to?

Answer 3

1) It’s colorless and forms when interstitial fluid enters the lymphatic capillaries.
2) Most similar to interstitial fluid, which is similar to plasma but has less protein.

Question 4

List the order of the flow of lymph

Answer 4

1) Lymphatic capillaries take in interstitial fluid, which becomes lymph
2) Lymphatic collecting vessels
3) Lymphatic trunks
4) Lymphatic ducts

Question 5

Are lymphatic vessels more similar to an artery, vein or capillary? Why?

Answer 5

Veins, because they both have unidirectional valves and thin walls

Question 6

Can you tell the difference between lymphatic capillaries and blood capillaries?

Answer 6

Yes; Unlike blood capillaries, fluid can flow into lymph capillaries but can’t flow out through the cell walls

Question 7

Do blood capillaries or lymph capillaries have valves? Which is more permeable?

Answer 7

Lymphatic capillaries have valves formed by overlapping endothelial cells; they’re more permeable than blood capillaries.

Question 8

What structure starts the thoracic duct, where does it empty into and what parts of the body does it drain?

Answer 8

The cisterna chyli starts the thoracic duct, which empties into the lefts subclavian vein. It drains the right and left abdomen, right and left legs, left arm and upper body, left thoracic region

Question 9

What drains the upper part of the right side of the body and where does it empty into?

Answer 9

The right lymphatic duct drains the right head, neck, thorax, and arm. It drains into the right subclavian vein.

Question 10

Can you name the six major cells of the lymphatic tissues and what functions they perform?

Answer 10

1) Natural Killer/ NK cells: large lymphocytes that attack bacteria, transplanted tissue, viral-infected cells, or cancer
2) T-lymphocytes (T-cells): Each T-cell develops unique antigen receptors that correspond to a specific antigen while in the thymus; once given these receptors they’re activated, which means they can recognize antigens presented to them.
3) B-lymphocytes (B-cells): Activation causes proliferation and differentiation into plasma cells that produce antibodies
4) Macrophages: large phagocytes that develop from monocytes; work as antigen-presenting cells for T-cells
5) Dendritic cells: branched, mobile antigen-presenting cells found in the epidermis, mucosal membranes, and lymphatic organs
6) Reticular cells: form the stroma (soft skeleton) of a lymphatic organ

Question 11

List the 4 types of T-cells and describe what they do

Answer 11

1) Cytotoxic T cells: attack enemy cells.
2) Helper T cells: promote cytotoxic t-cell and b-cell activation.
3) Regulatory T cells: inhibit multiplication and cytokine secretion by other T cells and limit immune response.
4) Memory T cells: are responsible for memory and cellular immunity.

Question 12

1) Which lymphatic cell type matures in the thymus?
2) Which lymphatic cell gives rise to plasma cells that produce antibodies?
3) Which lymphatic cell is capable of attacking cancerous cells or an organ transplant recipient?

Answer 12

1) T-cells mature in the thymus
2) B-cells
3) NK cells

Question 13

What type of lymphatic cell forms the soft skeleton of the lymphatic organ?

Answer 13

Reticular cells

Question 14

What are the two primary lymphatic organs? Why are they the only two considered to be primary lymphatic organs?

Answer 14

1) Red bone marrow and thymus.
2) There are only two because those are the only two places where lymphatic cells are ‘made and educated’

Question 15

1) What are three secondary lymphatic organs?
2) What does it mean if a cell is immunocompetent?

Answer 15

1) Lymph nodes, tonsils, and the spleen.
2)Immunocompetent cells have receptors for an antigen and are able to recognize and respond to it

Question 16

Describe the structure and function of the red bone marrow and thymus

Answer 16

1) Red bone marrow:
a) Structure: Soft, loosely organized, highly vascular material that’s separated from osseous tissue by the endosteum of bone
b) Function: Hemopoiesis and immunity
2) Thymus:
a) Structure: A bilobed organ located in the superior mediastinum that shows degeneration with age. The lobules are divided into cortex and medulla.
b) Function: T-lymphocytes develop in the cortex and move to the medulla. Produces signaling molecules thymosin, thymopoietin, thymulin, interleukins, and interferon.

Question 17

Describe the structure and function of the lymph nodes and tonsils

Answer 17

1) Lymph nodes:
a) Structure: An elongated, bean-shaped structure with a hilum that’s enclosed with a fibrous capsule with trabeculae that divide its interior into compartments. Its two regions are cortex and medulla.
b) Functions: Cleanse the lymph and act as a site of T and B cell activation.
2) Tonsils:
a) Structure: Patches of lymphatic tissue located at the entrance to the pharynx that are covered with epithelium and have deep pits (tonsillar crypts) which are lined with lymphatic nodules.
b) Function: Guard against ingested or inhaled pathogens.

Question 18

Describe the structure and function of the spleen

Answer 18

1) Structure: The largest lymphatic organ; made up of red and white pulp. Red pulp are sinuses filled with RBCs, and white pulp is lymphocytes and macrophages surrounding the small branches of the splenic artery.
2) Function: Produces RBCs in fetuses and breaks down old RBCs, stabilizes blood volume through plasma transfers to the lymphatic system, and white pulp monitors for foreign antigens and keeps an army of monocytes for release when needed.

Question 19

What is metastasis and why is this a concern?

Answer 19

1) Metastasis is when cancerous cells break free from the original tumor, travel to other sites in the body, and establish new tumors
2) It’s a concern for the lymphatic system because metastasizing cells easily enter lymph vessels and get lodged in the first lymph nodes they encounter. They then multiply in the lymph node and destroy it, and swim on to the next node.

Question 20

1) Define pathogen
2) Is our immune system an organ system? Why or why not?

Answer 20

1) Pathogens are defined as agents capable of producing disease. Includes bacteria, viruses, and fungi.
2) Our immune system is an organ system because its made up of the functions of multiple organs and vessels.

Question 21

What is the composition of the first line of defense and what’s its purpose?

Answer 21

1) Composition: Skin and mucous membranes; acid mantle and fluid flow
2) Purpose: Keep pathogens out of the body

Question 22

What is the composition of the second line of defense and what’s its purpose?

Answer 22

1) Composition: Protective cells (leukocytes, macrophages, NK cells), protective proteins (interferons and complement proteins), and protective responses (fever and inflammation)
2) Purpose: Keep the pathogen from replicating and spreading throughout the body

Question 23

1) What is the purpose of histamine and which cell types produce this substance?
2) What is the purpose of heparin and what cell types produce this substance?
3) What is the difference between a fixed and a wandering macrophage?

Answer 23

1) Basophils secrete histamine which promotes inflammation.
2) Basophils secrete heparin which inhibits clot formation.
3) Wandering macrophages seek out pathogens, whereas fixed macrophages only kill pathogens that come to them.

Question 24

1) Why does an NK cell release perforins?
2) What does an NK cell secrete to cause death?
3) Which leukocyte does phagocytosis on the enemy cell?

Answer 24

1) NK cells release perforins to create pores in the cell
2) NK cells secrete granzymes to induce apoptosis (programmed cell death)
3) Neutrophils can kill bacteria using phagocytosis and digestion

Question 25

Which cells release interferon and what ends of happening to that cell? Which cells benefit from interferon being released?

Answer 25

Interferon is secreted by certain cells infected by viruses to alert neighboring cells, doesn’t benefit the cell itself. Activates NK cells and macrophages and causes the alerted cell to synthesize anti-viral proteins

Question 26

List the 4 methods that the complement system uses and describe them

Answer 26

1) Inflammation: Stimulates mast cells and basophils to secrete histamine; activates and attracts neutrophils and macrophages
2) Immune clearance: Binds with antigen–antibody (Ag-Ab) complexes to red blood cells, so when they circulate through liver and spleen, macrophages strip off and destroy the Ag–Ab complexes leaving RBCs unharmed. Principal means of clearing foreign antigens from the bloodstream.
3) Phagocytosis: Assists phagocytes by opsonization (coating microbial cells)
4) Cytolysis: Forms a Membrane Attack Complex, which forms a hole in the target cell. This causes electrolytes to leak out, water to flow in rapidly, and the cell to rupture

Question 27

What organ controls elevation of body temperature? What protein is released?

Answer 27

1) The hypothalamus of the brain controls the elevation of body temperature
2) Promotes interferon activity

Question 28

Are all fevers beneficial? Why or why not? What are the 4 signs of inflammation?

Answer 28

1) Moderate fevers are helpful because they promote interferon activity, elevate metabolic rate and accelerates tissue repair, and inhibits reproduction of bacteria and viruses.High temperatures are harmful because we can cause brain damage and denature our own proteins.
2) Heat, pain, redness, swelling

Question 29

Can you correctly order the steps in the mobilization of defenses?

Answer 29

1) Step 1: Release of inflammatory chemicals such Histamine and other cytokines (from basophils, mast cells, damaged cells, toxins, etc.)
2) Step 2: The chemicals cause Vasodilation, which increases blood flow (local hyperemia). Hyperemia helps washes toxins and metabolic waste from area
3) Step 3: The chemicals increase capillary permeability. Fluid, leukocytes, and plasma proteins leave blood. Edema occurs
4) Step 4: Neutrophils leave bloodstream to injury site; accumulate within an hour. Margination, diapedesis, and chemotaxis occur.
5) Step 5: Fibrinogen (and other clotting factors) released in interstitial fluid clots to wall off microbes.

Question 30

Define margination, diapedesis, and chemotaxis

Answer 30

1) Margination: Selectins cause leukocytes to adhere to blood vessel walls
2) Diapedesis (emigration): Leukocytes squeeze between endothelial cells into tissue space
3) Use chemotaxis to guide them to the injury site.

Question 31

What do edema and hyperemia do?

Answer 31

1) Edema contributes to tissue cleanup; forces more fluid into lymphatic system
2) Hyperemia delivers oxygen, amino acids, and other necessities for protein synthesis

Question 32

What leukocyte arrives first to bacterial infections? What is the primary agent of tissue cleanup?

Answer 32

1) Neutrophils typically arrive first to a bacterial infection.
2) Monocytes are the primary agents of tissue cleanup and repair.

Question 33

What are the three characteristics that distinguish adaptive immunity from innate immunity?

Answer 33

1) Systemic effect: throughout the body
2) Specificity: immunity directed against a particular pathogen
3) Memory: when reexposed to the same pathogen, the body reacts so quickly that there is no noticeable illness

Question 34

What is the difference between cellular immunity and humoral immunity and which is better on extracellular pathogens and which is better for intracellular pathogens?

Answer 34

1) Cellular (cell-mediated) immunity: T-Cells directly attack and destroy foreign cells or diseased host cells and gets rid of intracellular pathogens by killing the cell
2) Humoral (antibody-mediated) immunity: B-Cells into plasma cell which secrete antibodies. Antibodies do not directly destroy a pathogen but tag it for destruction; works on extracellular stages of infections

Question 35

What’s the difference between natural immunity and artificial immunity? What’s the difference between active and passive immunity?

Answer 35

1) Natural immunity means you got sick
2) Active immunity means your body made the antibodies

Question 36

Can you define antigen, epitope, hapten and relate to how an antibody would react?

Answer 36

1) Antigen: any molecule that triggers an immune response
-An antibody would bind to it
2) Epitope: a fragment of an antigen presented by an antigen-presenting cell
-This is directed at T-cells, not antibodies.
3) Hapten: things that can trigger an immune response by combining with a host macromolecule and creating a complex that the body recognizes as foreign, but they’re too small to be antigenic in themselves. Afterwards, haptens alone can trigger a response.
-An antibody would bind to it if it has combined with a host macromolecule

Question 37

What are the three classes of lymphocytes? Which are third line of defense and which are second?

Answer 37

1) T-lymphocytes: third line of defense
2) B-lymphocytes: third line of defense
3) Natural Killer (NK) cells: second line of defense

Question 38

What are the three stages in a T cell’s life? What organs/tissues are involved in each stage of a T cell’s life cycle?

Answer 38

1) Born in bone marrow
2) Educated in thymus
3) Deployed to carry out immune function in lymphatic tissues and organs

Question 39

Can you explain what it means to be in a naïve lymphocyte pool or what deployment means?

Answer 39

1) Naive lymphocyte pool: immunocompetent T cells that have not yet encountered foreign antigens
2) Deployment: Naive T cells leave thymus and colonize lymphatic tissues and organs everywhere in the body

Question 40

What are the three stages in a B cell’s life? What organs/tissues are involved in each stage of a B cell’s life cycle?

Answer 40

1) Born in red bone marrow
2) Educated in red bone marrow
3) Deployed to same lymphatic tissues and organs as T cells

Question 41

Why does a T cell need an antigen presenting cell? What four cells are antigen presenting cells? What protein class acts as an identification tag?

Answer 41

1) T-cells cannot recognize antigens on their own
2) Dendritic cells, macrophages, reticular cells, and B cells
3) Major histocompatibility (MHC) complex proteins

Question 42

What does an antigen presenting cell display in the grooves of the class of protein that acts as an identification tag? What organelle helps antigen presenting cells process foreign antigens?

Answer 42

1) Epitopes are displayed in the grooves of the MHC protein.
2) Phagolysosomes

Question 43

What will a T cell do if the antigen presenting cell is displaying a self-antigen? A nonself-antigen?

Answer 43

Ignores self-antigens, attacks nonself-antigens

Question 44

What is cellular mediated immunity? What do the T lymphocytes do? Do you directly attack and kill with cellular immunity?

Answer 44

Cellular mediated immunity is when T lymphocytes directly attack and destroy diseased or foreign cells. Then the immune system remembers the antigens and prevents them from causing disease in the future

Question 45

Which is the effector T cell of cellular immunity? What type helps in both innate and adaptive immunity? Which helps prevent the body from overreacting i.e., limits your immune response?

Answer 45

1) Cytotoxic T-cells
2) Helper T-cells
3) Regulatory T-cells

Question 46

Can you explain the three Rs of immunity- recognize, react and remember?

Answer 46

Recognition: Recognize
Attack: React
Memory: Remember

Question 47

What is the purpose of costimulation for a T cell?

Answer 47

Costimulation is important because it helps ensure the immune system does not launch an attack in the absence of an enemy, in which case it would turn against one’s own body and injure our tissues

Question 48

A T cell releases perforin and granzymes just like ______________________.
What happens to the T cell after releasing chemicals, does it die?

Answer 48

1) NK cells
2) They undergo repeated mitosis

Question 49

What is the T cell recall response?

Answer 49

The idea that upon re-exposure to same pathogen later in life, memory cells launch a quick attack so that no noticeable illness occur. The person is immune to the disease

Question 50

1) What is humoral immunity; do you directly attack and kill with humoral immunity?
2) Which type of T cell helps B cells get activated?
3) What do we call a B cell that has come in contact with its specific antigen?

Answer 50

1) B lymphocytes produce antibodies that bind to antigens and tag them for destruction by other means; you do not directly attack and kill.
2) Helper T cells: bind to a Ag–MHC protein complex and secretes interleukins that activate B cell
3)Immunocompetent

Question 51

1) What is clonal selection?
2) What type of cell is the B cell differentiating into?
3) What will that cell secrete, and what 2 organelles do you expect that cell to have a lot of?

Answer 51

1) Clonal selection is when interleukins secreted by a helper T cell triggers a B cell to quickly replicate
2) Plasma cells
3) Plasma cells secrete antibodies, so you’d expect them to have a lot of rough ER.

Question 52

Define immunoglobulin. What letter of the alphabet does an antibody look like?

Answer 52

1) Immunoglobulin (IG): an antibody; a defensive gamma globulin found in blood plasma, tissue fluids, body secretions, and some leukocyte membranes
2) Antibodies are shaped like the letter Y

Question 53

Can you differentiate between the five classes of antibodies?

Answer 53

1) IgG: 80% of total; a monomer; most abundant and diverse; crosses placenta to fetus; secreted in secondary immune response; complement fixation
2) IgA: 10-15% of total; monomer in plasma; dimer in secretions (mucus, saliva, tears, breast milk, and intestinal secretions; too large to cross placenta.) Prevents pathogen adherence to epithelia and penetrating underlying tissues
3) IgM: 5-10% of total, pentamer; secreted in primary immune response (indicates a current infection); agglutination during ABO incompatibility; complement fixation
4) IgD: 0.02% of total, monomer; B cell transmembrane antigen receptor. Thought to function in B cell activation by antigens
5) IgE: 0.002% of total, monomer; transmembrane protein on basophils and mast cells causing release of histamine when activated.

Question 54

1) Which immunoglobin type crosses the placenta to the fetus?
2) Which type is in body secretions?
3) Which type is a pentamer and indicates a current infection? 4) Which helps in B cell activation? 5) Which is on basophils or masts cells?

Answer 54

1) IgG crosses placenta to fetus
2) IgA is in body secretions
3) IgM is a pentamer and indicates infection
4) IgD helps in B-cell activation
5) IgE is on basophils and mast cells

Question 55

Can you briefly explain how antibodies work? What is neutralization? What is complement fixation and what does it lead to? What is agglutination? What is precipitation?

Answer 55

Antibodies have 4 mechanisms of attack against antigens:
1) Neutralization: Antibodies mask pathogenic region of antigen
2) Complement fixation: Leads to inflammation, phagocytosis, immune clearance, or cytolysis
3) Agglutination: Antibody has 2 to 10 binding sites; binds to multiple enemy cells, immobilizing them from spreading. Enhances phagocytosis by creating “bigger bites”
4) Precipitation: Antibody binds antigen molecules (not cells); creates antigen–antibody complex that precipitates, allowing them to be removed by immune clearance or phagocytized by eosinophils.

Question 56

1) Can you explain the primary immune response?
2) Which antibody class appears first?
3) What is going on with your health during the lag time of the primary immune response; why is there lag time?

Answer 56

1) Primary immune response: The immune reaction brought about by the first exposure to an antigen. Has a lag period (3-6 days) while naive B cells multiply and differentiate into plasma cells. As plasma cells produce antibodies, the antibody titer (level in the blood plasma) rises
2) IgM appears first, peaks in about 10 days, soon declines
3) During the lag period, which is needed for naive B cells to multiply and differentiate into plasma cells, you get sick.

Question 57

1) If you have the IgG antibody present, what does that indicate?
2) Is there a lag if you have secondary response? What is going on with your health during the secondary immune response?

Answer 57

1) If you have the IgG antibody, the you were either sick during the lag time of primary immune response about 11-14 days ago, or you’ve been re-exposed to an antigen and have long-term immunity
2) No lag time in secondary response; totally healthy

Question 58

Compare and contrast what cellular and humoral immunity are best for, their effector cells, and their memory

Answer 58

1) Cellular Immunity:
a) Best for: Intracellular pathogens, cancer cells, transplanted tissues
b) Effector cells: Cytotoxic T cells (helped by Helper T cells)
c) Memory: usually last life-time
2) Humoral Immunity:
a) Best for: extracellular pathogens, toxins, venoms, allergens, mismatched RBCs
b) Effector cells: Plasma cells (develop from B cells and helped by Helper T cells)
c) Memory: does not last as long as cellular immunity

Question 59

Can you define hypersensitivity, alloimmunity, autoimmunity, allergen, allergy, and anaphylaxis?

Answer 59

1)Hypersensitivity: an excessive immune reaction against antigens that most people tolerate. Includes alloimmunity, autoimmunity, and allergies.
2) Alloimmunity: Transplanted organs
3) Autoimmunity: When your body uses immune responses against itself
4) Allergen: A particle that can cause a type 1 hypersensitivity reaction
5) Allergy: A type I hypersensitivity reaction
6) Anaphylaxis: an immediate, severe type I reaction; local anaphylaxis can be relieved with antihistamines

Question 60

What are the four types of hyper sensitivity? Which is T cell based? Which are antibody based?

Answer 60

1) Type I acute (immediate) hypersensitivity
-Very rapid response
-Based on antibodies
2) Type II and Type III subacute hypersensitivity
-Slower onset (1 to 3 hours after exposure)
-Last longer (10 to 15 hours)
-Based on antibodies
3) Type IV: delayed cell-mediated response
-Signs appear 12 to 72 hours after exposure
-Cosmetics, poison ivy, graft rejection, TB skin test
-T-cell based

Question 61

1) In a type 1 reaction, what contact causes the person to have symptoms; is it the first, second or all exposures to the allergen?
2) If you have a reaction to poison ivy, this is what type of hypersensitivity?

Answer 61

1) In type I (acute), the initial contact is asymptomatic but sensitizes person. The second contact causes symptoms.
2) Poison ivy is type IV hypersensitivity.

Question 62

What treatment would be prescribed for a person going into anaphylactic shock and why?

Answer 62

-Antihistamines are inadequate by themselves
-Epinephrine relieves the symptoms by dilating bronchioles, increasing cardiac output, and restoring blood pressure
-Fluid therapy and respiratory support are sometimes required

Question 63

AIDs is caused by what virus? What T cells is destroyed by the virus?

Answer 63

1) Human immunodeficiency virus (HIV)
2) Helper T-cells

Question 64

1) What are common signs and symptoms of HIV/AIDS?
2) How is the virus transmitted? 3) What does the virus do to the immune system?

Answer 64

1) Early symptoms: flu-like symptoms of chills and fever. Progresses to night sweats, fatigue, headache, extreme weight loss, lymphadenitis. Susceptibility to opportunistic infections, candida (thrush), kaposi sarcoma (cancer)
2) HIV is transmitted through blood, semen, vaginal secretions, breast milk, or across the placenta. By sexual intercourse (vaginal, anal, oral), contaminated blood products, and contaminated needles; not by casual contact.
3) By destroying TH cells, HIV strikes at the central coordinating agent of innate defense, humoral immunity, and cellular immunity

Question 65

What are the four principal mechanisms of communication between cells? Describe them

Answer 65

1) Gap junctions: Allow molecules, nutrients, and electrolytes to move from cell to cell
2) Neurotransmitters: Released from presynaptic neurons to postsynaptic neurons
3) Paracrines: Secreted into tissue fluids to affect nearby cells
4) Hormones: Chemical messengers that travel in the bloodstream to other tissues and organs

Question 66

The endocrine system consists of glands, tissues and cells that secrete what? Define endocrinology

Answer 66

1) Hormones
2) Endocrinology: the study of the endocrine system and the diagnosis and treatment of its disorders

Question 67

What properties does a hormone have? (3)
What are some endocrine glands?

Answer 67

1) Properties:
a) They’re chemical messengers
b) They’re transported by the bloodstream. c) They stimulate physiological responses in target cells
2) Examples of endocrine glands include the thyroid, pituitary gland, hypothalamus, and pancreas.

Question 68

How do exocrine and endocrine glands secrete their products? Which has external secretions; which have internal secretions?

Answer 68

1) Exocrine glands use ducts, endocrine glands do not.
2) Exocrine glands have external secretions, whereas endocrine glands have internal secretions.

Question 69

What are examples of exocrine secretions? What are examples of endocrine secretions?

Answer 69

1) Examples of exocrine secretions include sweat, tears, digestive juices, and saliva
2) Examples of endocrine secretions include the secretion of hormones (ADH, FSH, OT, ACTH, GH, etc)

Question 70

1) In comparing the nervous system to the endocrine system, what is something they have in common regarding specificity, receptors, and communication? 2) Both neurotransmitters and hormones depend on target cells to provide what?

Answer 70

1) Both rely on their targets having receptors, both serve for internal communication, several chemicals act as both hormones and neurotransmitters, and both systems can have a similar effect on target cells.
2) The targets of the nervous and endocrine systems (the postsynaptic neuron and target organ/cells respectively) both must have receptors.

Question 71

In comparing the nervous system to the endocrine system, what is different regarding speed and persistence of response, adaptation to long-term stimuli and area of effect? Is one more focused on a particular organ or limited number of cells or does one have a more widespread effect?

Answer 71

1) The nervous system has a quicker but more short-lived response than the endocrine system; it may take the endocrine system seconds or days to respond, but the effect can last for days or longer.
2) The nervous system adapts quickly to long-term stimuli and the response declines, whereas the endocrine system adapts more slowly and response persists.
3) The nervous system is targeted and specific (one organ) whereas the endocrine system is general and widespread (many organs)

Question 72

1) Give 3 examples of chemicals that function both as neurotransmitters and hormones. 2) Some hormones and neurotransmitters produce identical effects on the same targets, can you think of an example?

Answer 72

1) Norepinephrine, dopamine, and ADH
2) Norepinephrine and glucagon both cause glycogen hydrolysis in liver

Question 73

1) How does the nervous and endocrine systems regulate each other?

Answer 73

1) Neurotransmitters can affect glands, and hormones can affect neurons

Question 74

1) Where is the location of the hypothalamus? 2) List some of the primitive functions it regulates.
3) How is the pituitary gland connected to the hypothalamus, what is the name of the stalk?
4) The pituitary gland is housed in a depression of which bone and its bone marking?

Answer 74

1) The hypothalamus is above the pituitary gland in the brain
2) Water balance, thermoregulation, sex drive, childbirth
3) The pituitary gland is connected by the stalk called the infundibulum.
4) The pituitary gland is housed in the sella turcica of the sphenoid bone.

Question 75

Which structure of the pituitary has no nervous connection to the hypothalamus? How is it linked to it then?

Answer 75

The anterior pituitary is connected to the hypothalamus by the hypophyseal portal system.

Question 76

What does the hypophyseal portal system consist of, and where are these things located?

Answer 76

The primary capillary bed in the hypothalamus and the secondary capillary bed in the anterior pituitary.

Question 77

How many hormones (by number) are released by the hypothalamus that regulate the anterior pituitary? Of that number, how many stimulate release and how many inhibit release?

Answer 77

6 hormones; 4 stimulate and 2 inhibit (PIH and somatostatin)

Question 78

1) Can you list the 6 hormones released by the anterior pituitary? 2) Can you list the 6 hypothalamic hormones that control the hormones released from the anterior pituitary?

Answer 78

1) FSH, LH, ACTH, TSH are the tropic hormones; PRL and GH are non-tropic.
2) TRH, CRH, GnRH, and GHRH promote secretion; PIH and somatostatin inhibit.

Question 79

1) The posterior pituitary constitutes the posterior one-quarter of the pituitary. How does the hypothalamus connect with it? 2) What are the names of the two hormones stored here?
3) What causes the hormones stored in the posterior pituitary to be released?

Answer 79

1) The hypothalamo-hypophyseal tract (nerves).
2) ADH and OT are stored in the posterior pituitary. 3) They’re released by an action potential moving down the nerve

Question 80

1) In summary, how many total hormones are released by the hypothalamus? 2) How many regulate the anterior pituitary? 3) Of the hormones in the posterior pituitary, how many were produced by the posterior pituitary?

Answer 80

1) There are 8 hypothalamic hormones
2) 6 regulate the anterior pituitary. 3) Neither of the 2 hormones stored in the posterior pituitary were produced there.

Question 81

1) What does FSH target?
2) What does LH stimulate in females? In males?
3) What hypothalamic hormone stimulates release of FSH and LH?

Answer 81

1) The gonads
2) In females it stimulates ovulation, stimulates corpus luteum to secrete progesterone. In males it stimulates testes to secrete testosterone
3) GnRH releases FSH and LH

Question 82

1) TSH stands for what?
2) What organ does TSH target, and what hormone is stimulated to be released?
3) What hypothalamic hormone stimulates release of TSH; what hypothalamic hormone inhibits release of TSH?

Answer 82

1) Thyroid stimulating hormone.
2) Targets the thyroid to release thyroid hormone. 3) TRH stimulates the release of TSH, somatostatin inhibits the release of TSH.

Question 83

1) ACTH stands for what?
2) What specific part of an organ does ACTH target, and what hormone is stimulated to be released?
3) What hypothalamic hormone stimulates release of ACTH?

Answer 83

1)Adrenocorticotropic hormone
2) It stimulates the adrenal cortex to secrete glucocorticoid.
3) Corticotropin-releasing hormone (CRH) stimulates its release.

Question 84

1) What does PRL stand for?
2) What organ does PRL target, and what is stimulated to be released?
3) What hypothalamic hormone stimulates release of PRL; what hypothalamic hormone inhibits release of PRL?

Answer 84

1) PRL stands for prolactin.
2) Targets the mammary glands to produce milk.
3) TRH promotes the release of PRL; PIH inhibits the release of PRL.

Question 85

1) What does GH stand for?
2) What does GH do?
3) What hypothalamic hormone stimulates release of GH; what hypothalamic hormone inhibits release of GH? Note that the hypothalamic hormone that inhibits release of GH, is the same that inhibits release of what other anterior pituitary hormone?

Answer 85

1) GH stands for growth hormone, 2) It primarily stimulates mitosis and cellular division; this increases blood glucose, lipid metabolism, and blood glucose levels.
3) GHRH stimulates its release and somatostatin inhibits its release (also inhibits the release of TSH).

Question 86

1) What does ADH do? (hint… kidneys)?
2) Why is it also called vasopressin?
3) Hyposecretion results in what disorder? What is the classic symptom?

Answer 86

1) It increases water retention by the kidneys.
2) It’s also called vasopressin because it can cause vasoconstriction.
3) Diabetes insipidus, and its classic symptom is polyuria.

Question 87

Oxytocin (OT) has a variety of reproductive functions ranging from intercourse to birth to breast-feeding. Can you give some examples of its functions?

Answer 87

1) A surge of OT is released during sexual arousal and orgasm; promotes feelings of sexual satisfaction and emotional bonding between partners. 2) Stimulates labor contractions during childbirth and stimulates flow of milk during lactation (both positive feedback mechanisms); may promote emotional bonding between lactating mother and infant

Question 88

1) In times of stress, this triggers ACTH secretion, what does this lead to? 2) During pregnancy, this induces prolactin secretion. What does this do?
3) High osmolarity triggers release of ADH. What does this do?
4) Infant suckling triggers release of OT, which does what?
5) What organ controls rate of pituitary hormone secretions?

Answer 88

1) Stimulates adrenal cortex to secrete glucocorticoids
2) Causes the mammary glands to grow.
3) Increases fluid retention by the kidneys; decreases osmolarity
4) Stimulates flow of milk
5) The hypothalamus (and cerebral control)

Question 89

1) Define negative feedback.
2) Using the pituitary–thyroid system, how would negative feedback inhibition occur? 3) Can you think of an example of where a hormone triggers a positive feedback cycle?

Answer 89

1) Negative feedback: increased target organ hormone levels inhibit release of hypothalamic and/or pituitary hormones
2) Higher levels of thyroid hormone inhibits release of TRH by hypothalamus and of TSH by anterior pituitary
3) Stretching of uterus increases OT release, causes contractions, causing more stretching of uterus, etc. until delivery

Question 90

1) The pineal gland is located where?
2) The pineal gland’s function is somewhat mysterious; it may play a role in establishing ____________ rhythms of physiological function.
3) During the night it synthesizes what?

Answer 90

1) The pineal gland is located in the brain posterior to the hypothalamus.
2) Circadian
3) At night the pineal glad synthesizes melatonin.

Question 91

The thymus is located where? What organ systems does it play a role in? It’s the site of maturation for what cells?

Answer 91

The thymus is located just above the ascending aorta, and it plays a role in the endocrine, lymphatic, and immune systems (maturation of T cells).

Question 92

1) How does the thymus change in terms of size over the course of a person’s life?
2) What does it secrete?

Answer 92

1) The thymus shrinks/ undergoes involution after puberty.
2) It secretes thymopoietin, thymosin, and thymulin.

Question 93

1) The thyroid is located where? 2) Thyroid follicles are filled with a protein-rich colloid and lined with a simple ____________ epithelium of follicular cells.
3) What does it secrete, and in response to what stimulus from the pituitary?

Answer 93

1) Located in the neck at an isthmus below the larynx.
2) simple cuboidal epithelium
3) It secretes T3 and T4 (thyroid hormone) in response to TSH.

Question 94

1) What is the primary effect of TH?
2) What does TH do in terms of oxygen consumption? What does it do to the respiratory rate, heart rate and strength of the heartbeat? What about the appetite?

Answer 94

1) The primary effect of TH is increasing metabolism.
2) It also increases oxygen consumption, heat production, appetite, growth hormone secretion, alertness, reflex speed.

Question 95

1) The thyroid gland also contains nests of C (clear) cells, or _______________ cells, between the follicles.
2) These cells secrete what? When/why do they secrete this? What do they decrease the level of?

Answer 95

1) parafollicular
2) They secrete calcitonin when blood calcium rises to decrease the blood calcium.

Question 96

In terms of thyroid disorders, explain what causes Grave’s disease, cretinism and myxedema

Answer 96

1) Graves disease: Thyroid hypersecretion due to autoantibodies mimicking the effect of TSH.
2) Cretinism: Congenital thyroid hyposecretion.
3) Myxedema: Adult thyroid hyposecretion.

Question 97

1) The parathyroid glands are located where? How many of them are there? 2) What do they secrete? They secrete this hormone in response to what being low? What do they increase the level of?

Answer 97

1) Located on the back of the thyroid gland, there’s usually 4 parathyroid glands.
2) They secrete parathyroid hormone in response to low blood calcium levels, and increase the level of calcium.

Question 98

In terms of parathyroid disorders, be able to explain hypoparathyroidism and hyperparathyroidism; what causes them and what do they do?

Answer 98

1) Hypoparathyroidism is often due to surgical excision during thyroid removal, causes fatal tetany (spasms in larynx) due to low blood calcium
2) Hyperparathyroidism is often due to a parathyroid tumor and promotes renal calculi formation and soft, deformed bones

Question 99

1) The outer region of the adrenal gland is known as? The inner region is known as?
2) The adrenal medulla has a dual nature, what does this mean?

Answer 99

1) The outer region is the cortex, the inner region is the medulla
2) It’s both an endocrine gland and a ganglion of the sympathetic nervous system

Question 100

1) What cell releases catecholamines and under what conditions are they usually released?
2) What are the two major catecholamines?

Answer 100

1) Chromaffin cells of the adrenal medulla, which are modified sympathetic postganglionic neurons release catecholamines into the bloodstream when stimulated.
2) Epinephrine and norepinephrine

Question 101

1) How does the adrenal medulla increase alertness and prepare the body for physical activity?
2) What does it have the liver do? 3) Why is epinephrine inhibiting insulin secretion?

Answer 101

1) The adrenal medulla mobilizes high-energy fuels, lactate, fatty acids, and glucose.
2) It mobilizes glucose by causing glycogenolysis and gluconeogenesis by liver
3) Epinephrine inhibits insulin secretion to keep the blood glucose levels higher for the brain to use.

Question 102

1) When the adrenal medulla is increasing blood flow to muscles, where would you decrease blood flow?
2) What about heart rate, BP and airflow; do you increase or decrease?

Answer 102

1) Decrease blood flow to the digestive system and urinary system.
2) Increase blood pressure, heart rate, pulmonary airflow, and metabolic rate

Question 103

1) What is the function of aldosterone? Will this increase or decrease blood volume and blood pressure?
2) What does it mean to be part of RAA?

Answer 103

1) Aldosterone promotes sodium retention and potassium secretion; this promotes higher blood volume and blood pressure.
2) It means it’s a part of the renin-angiotensin-aldosterone system.

Question 104

1) The adrenal cortex, has three categories of hormones. Glucocorticoids stimulate what?
2) These hormones have what type of effect on inflammation? What does excessive secretion suppress?

Answer 104

1) Glucocorticoids (i.e. cortisol) stimulate gluconeogenesis and fat and protein catabolism.
2) Glucocorticoids (i.e. cortisol) has an anti-inflammatory effect, but this becomes immune suppression with long-term use.

Question 105

What do the sex steroids release?

Answer 105

Androgens and estradiol

Question 106

In terms of adrenal disorders, be able to explain:
1) Cushing syndrome
2) Adrenogenital syndrome (AGS), 3) Addison’s disease, including symptoms

Answer 106

1) Cushing syndrome: Cortisol hypersecretion.
a) Symptoms: Hyperglycemia, hypertension, weakness, edema. Also causes rapid muscle and bone loss due to protein catabolism, and abnormal fat deposition (moon face and buffalo hump)
2) Adrenogenital syndrome (AGS): Adrenal androgen hypersecretion (accompanies Cushing)
a) Symptoms: causes enlarged external sexual organs in children and early puberty. Masculinizing effects on females.
3) Addison’s disease: Cortisol and/or aldosterone hyposecretion.
a) Symptoms: Hypoglycemia, hypotension, weakness, weight loss, and hyperpigmentation

Question 107

The pancreas located where? Is it endocrine, exocrine or both?

Answer 107

The pancreas is located between the kidneys; it is both endocrine and exocrine.

Question 108

1) Which cell type releases glucagon? When does glucagon get released?
2) What effect does glucagon have on the liver? 3) How does it affect adipose tissue?

Answer 108

1) The alpha cells in the pancreatic islets release glucagon when blood glucose gets low between meals; glucagon raises glucose.
2) In the liver, glucagon stimulates gluconeogenesis & glycogenolysis
3) Causes lipolysis of adipose tissue.

Question 109

1) Which cell type releases insulin? When does insulin get released?
2) What hormone does it antagonize?
3) An insufficiency or inaction of this hormone is the cause of what?

Answer 109

1) Beta cells in the pancreatic islets release insulin in response to high blood glucose after a meal; insulin lowers blood glucose.
2) It’s an antagonist to glucagon.
3) An insufficiency or inaction of insulin causes diabetes mellitus.

Question 110

1) Define polyuria, polydipsia and polyphagia.
2) What are the symptoms of diabetes mellitus as it relates to polyuria, polydipsia and polyphagia, and as it relates to blood tests and urinalysis?

Answer 110

1)
a) Polyuria: excessive urination
b) Polydipsia: excessive thirst
c) Polyphagia: excessive hunger
2) Diabetes mellitus causes all 3 of these symptoms because of elevated blood glucose, glucose in urine, and ketones in the urine. Polyuria is caused by the transport maximum of the kidneys.

Question 111

1) Explain Type 1 diabetes and why insulin is always used to treat type 1 but not type 2 diabetes mellitus.
2) Which type of diabetes mellitus is more prevalent?

Answer 111

1) Insulin is always used to treat type 1 diabetes mellitus because the problem is lack of insulin, whereas in type 2 diabetes mellitus the problem is insulin insensitivity.
2) Type 2 diabetes mellitus is far more common.

Question 112

1) What are risk factors for type 1? 2) What are risk factors for type 2?

Answer 112

1) Risk factors for type 1 are hereditary susceptibility; occurs when an individual gets sick and their autoantibodies attack the pancreatic beta cells.
2) Risk factors for type 2 are heredity, age (40+), obesity, and ethnicity (Native American, Hispanic, and Asian)

Question 113

Any hormone that raises blood glucose level is called a hyperglycemic hormone.
1) Can you list a hypoglycemic hormone?
2) What are some hyperglycemic hormones?

Answer 113

1) Hypoglycemic: Insulin
2) Hyperglycemic: Glucagon, growth hormone, epinephrine, norepinephrine, and cortisol

Question 114

1) Are the gonads, endocrine, exocrine or both endocrine and exocrine?
2) What other organ is similar to the gonads?

Answer 114

1) Gonads are both endocrine and exocrine
2) The pancreas is also both endocrine and exocrine

Question 115

1) Regarding the gonads, their exocrine products are whole cells, what are these cells called?
2) Their endocrine products are what?

Answer 115

1) Exocrine products: Eggs and sperm
2) Endocrine products: Gonadal hormones.

Question 116

1) The ovaries secrete chiefly estradiol, progesterone, and _________. 2) The testes secrete mainly _______________ and inhibin.

Answer 116

1) estradiol, progesterone, and inhibin.
2) testosterone, weaker androgens, estrogen, and inhibin.

Question 117

1) What are the functions of estrogen (estradiol) and progesterone?
2) What does inhibin suppress?

Answer 117

1) Development of female reproductive system and physique including adolescent bone growth, regulating the menstrual cycle, sustaining pregnancy, and preparing mammary glands for lactation
2) Inhibin suppresses FSH secretion from anterior pituitary in both sexes.

Question 118

1) Testosterone stimulates the development of what?
2) In males, by limiting ________________ secretion, inhibin regulates the rate of sperm production.

Answer 118

1) Testosterone stimulates development of male reproductive system in fetus and adolescent, and sex drive, and also sustains sperm production
2) In males, by limiting FSH secretion, inhibin regulates the rate of sperm production.

Question 119

1) What cells of the skin convert a cholesterol-like steroid into cholecalciferol using UV radiation from the sun?
2) The liver and kidneys convert cholecalciferol into what vitamin?

Answer 119

1) Keratinocytes
2) The liver and kidneys convert cholecalciferol into vitamin D.

Question 120

The kidneys secrete the hormone responsible for stimulating red blood cell production. Name kidney hormone and the target.

Answer 120

Erythropoietin targets red bone marrow.

Question 121

The kidneys secrete a hormone that stimulates production of aldosterone. Name kidney hormone and the target.

Answer 121

Renin, which targets the adrenal cortex

Question 122

Rising blood pressure stretches the heart wall and stimulates cardiac muscle to secrete atrial natriuretic peptides. What is the target and what is the action of the hormone?

Answer 122

The atrial natriuretic peptides target the kidneys to increase sodium and water excretion, which reduces blood volume and BP

Question 123

The stomach and small intestines contain enteroendocrine cells that secrete three hormones that coordinate motility and glandular secretion. Name the three hormones.

Answer 123

Cholecystokinin, gastrin, secretin

Question 124

Adipose cells secrete the hormone leptin, which has what action in the body?

Answer 124

Slows down appetite

Question 125

The placenta performs many functions during pregnancy, what hormones does it secrete and this has what action in the body?

Answer 125

Secretes estrogen, progesterone, and others. This regulates pregnancy and stimulates the development of the fetus and mammary glands

Question 126

Hormones fall into three chemical classes. What are those three chemical classes?

Answer 126

Steroids, peptides, and monoamines

Question 127

1) What are some steroid hormones and what are they derived from?
2) What are examples of peptide hormones and how are they synthesized?
3) What are some monoamine hormones?
4)Catecholamines refers to what hormones collectively?

Answer 127

1) Steroid hormones are cholesterol-derived hormones, and include sex steroids and corticosteroids.
2) Peptide hormones are chains of amino acids synthesized in the ribosome and include hormones from pituitary, hypothalamus, and insulin
3) Monoamine hormones are made from amino acids and include catecholamines, melatonin, thyroid hormone
4)Catecholamines refers to epinephrine and norepinephrine

Question 128

1) Describe the synthesis, storage, and secretion of thyroid hormone (TH). What two hormones collectively form TH? What element is required?
2) Specifically, chemically, what category class is TH in? In the body, does it behave based on its chemical classification?

Answer 128

1) Thyroid follicles absorb iodine from blood and use it to produce and release T3 and T4 when stimulated (by TSH)
2) Thyroid hormone is a monoamine, but it behaves like a steroid.

Question 129

1) Are all hormones secreted at the same rate?
2) Explain hormonal stimuli with examples using the tropic hormones.
3) Explain humoral stimuli with examples as is relates to blood-borne stimuli.

Answer 129

1) Hormones are not secreted at the same rate or a steady rate; some have daily or monthly rhythms and others are under the influence of stimuli (neural, hormonal, or humoral stimuli).
2) Hormonal stimuli is when one hormone triggers an organ to release another hormone. For example, TRH produced by the hypothalamus promotes the production of TSH by the anterior pituitary, which promotes the thyroid to produce TH.
3) Humoral stimuli refers to blood-borne stimuli. For example, high blood glucose stimulates the release of insulin, and low blood calcium stimulates the release of parathyroid hormone

Question 130

1) Which of the three chemical classes are considered hydrophilic, which are hydrophobic? 2) Do they mix with blood plasma? What hormone is the exception?

Answer 130

1) Steroids are hydrophobic, most monoamines and peptides are hydrophilic.
2) Steroids do not mix with blood plasma, monoamines and peptides do (thyroid hormone is the exception to this rule).

Question 131

1) If a hormone is hydrophobic, what transport proteins help the hormones get around the body?
2) Define half-life. 3) Which hormones have a longer half-life and why?

Answer 131

1) Albumins and globulins help transport hydrophobic hormones.
2) How long it takes for half of the chemical to degrade.
3) Bound (aka hydrophobic) hormones typically have a longer half-life because they’re protected from liver enzymes and kidney filtration.

Question 132

1) What does the cell have to have in order for the hormone to stimulate it?
2) Where is that going to be located?

Answer 132

1) The cell must have a receptor for that hormone. 2) Receptors can be found embedded in the plasma membrane, in the cytoplasm, or in the nucleus.

Question 133

Receptor–hormone interactions are similar to enzyme–substrate interactions. Unlike enzymes, receptors do not chemically change their ligands; they do, however, exhibit specificity and saturation.
1) Specificity means what?
2) Saturation is what?

Answer 133

1) They have a specific receptor for each hormone
2) They’re saturated when all of the receptors are occupied by molecules.

Question 134

Peptides and catecholamines are hydrophilic and cannot penetrate into target cells, so what must they bind to? Where is it located?

Answer 134

They bind to receptors on the surface of the cell and activate intracellular processes through second messengers

Question 135

1) Steroid hormones and thyroid hormone enter the target cell, so what they must bind to is sometimes in the cytoplasm, but more commonly is found in the __________
2) What is the function of steroid hormones and TH in a target cell? Steroid and thyroid hormones typically require how long in order to show an effect and why?

Answer 135

1) Steroid hormones and thyroid hormone enter the target cell, so what they must bind to is sometimes in the cytoplasm, but more commonly is found in the nucleus.
2) They influence the expression of genes in the target cell, but they take several hours to days to show effect due to lag for protein synthesis

Question 136

Thyroid hormone in the T4 form has little metabolic effect, but in the target cell cytoplasm, an enzyme converts T4 to the more potent T3. Once T3 enters the target cell nucleus and binds to receptors, what is one gene that you know it activates?

Answer 136

The sodium-potassium pump gene.

Question 137

What is signal amplification?

Answer 137

The concept that a small stimulus can have a huge effect.

Question 138

1) Target cells can modulate their sensitivity to a hormone by doing what? What happens in terms of sensitivity?
2) Can you give an example of why you might need to up-regulate or down regulate receptors?

Answer 138

1) Up-regulating (increasing the number of receptors) and down-regulating (decreasing the number of receptors)
2) It’s used to adjust target cell sensitivity, such as when a hormone is being chronically over or under produced.

Question 139

1) What are synergistic effects?
2) Can you list an example of a synergistic effect?
3) What are permissive effects?
4) Can you list an example of a permissive effect?

Answer 139

1) Multiple hormones act together for greater effect
2) Ex: Synergism between FSH and testosterone on sperm production
3) One hormone enhances the target organ’s response to a second later hormone
4) Ex: Estrogen prepares uterus for action of progesterone

Question 140

1) What are antagonistic effects?
2) Can you list examples of antagonistic effects?

Answer 140

1) One hormone opposes the action of another
2) Examples: Insulin lowers blood glucose and glycogen raises it, PTH raises blood calcium and calcitonin raises it

Question 141

1) Hormone clearance occurs when hormones are taken up and degraded by what two organs?
2) What two ways is it excreted?

Answer 141

1) By the liver or kidneys.
2) Excreted in bile or urine

Question 142

1) What does the respiratory system do?
2) What other system works closely to deliver oxygen?
3) What other system works with respiratory to help regulate acid-base balance?

Answer 142

1) The respiratory system consists of a system of tubes that delivers air to the lungs
2) Works with the cardiovascular system to deliver oxygen.
3) Works with urinary system to help regulate acid-base balance.

Question 143

What are the 8 functions of the respiratory system?

Answer 143

1) Gas exchange
2) Communication
3) Olfaction
4) Acid-base balance
5) Blood pressure regulation
6) Blood and lymph flow
7) Blood filtration
8) Expulsion of abdominal contents

Question 144

1) What are the principal organs of the respiratory system?
2) What is conducting division consist of?
3) What does the respiratory division consist of?

Answer 144

1) Major organs include the nose, pharynx, larynx, trachea, and lungs.
2) The conducting zone includes passages that serve only for airflow (no gas exchange)
3) The respiratory zone is where gas exchange takes place (alveoli)

Question 145

What is considered the upper respiratory tract? Lower respiratory tract?

Answer 145

The upper respiratory tract is in the head and neck, the lower respiratory tract is in the thorax.

Question 146

1) What are some of the functions of the nose? (3)
2) What type of cartilage makes up the nose?
3) The nose extends from _______ to the posterior nasal ____________.
4) What divides the nasal cavity?

Answer 146

1) 3 functions of the nose: a) Warms, cleanses, and humidifies inhaled air
b) Detects odors
c) Serves as a resonating chamber that amplifies voice
2) Made of hyaline cartilage
3) The nose extends from nostrils (nares) to posterior nasal apertures (choanae)
4) The nasal septum divides the nasal cavity.

Question 147

1) What is a meatus? What is the function of the meatus?
2) What are the conchae?
3) What is the scientific name of the wineglass-shaped cells in the respiratory epithelium and what do they secrete?

Answer 147

1) A meatus is the narrow air passage/ indent beneath each concha; it cleans, warms, and moistens air due to its narrowness and turbulence.
2) The conchae are the bumps between the meatuses.
3) Goblet cells, which secrete mucus.

Question 148

Are the cilia in the nasal cavity mobile?

Answer 148

Cilia in this area are mobile; they propel mucus posteriorly towards the pharynx to be swallowed

Question 149

1) What are the 3 regions of the pharynx?
2) Which region receives the auditory (eustachian) tubes from the middle ears and houses the pharyngeal tonsil?
3) Which region is a space between the posterior margin of the soft palate and the epiglottis?
4) Which region lies mostly posterior to the larynx, extending from the superior margin of the epiglottis to the inferior margin of the cricoid cartilage, where the esophagus begins?

Answer 149

1) Nasopharynx, oropharynx, and laryngopharynx
2) Nasopharynx
3) Oropharynx
4) Laryngopharynx

Question 150

1) What two regions of the pharynx pass air, food, and fluids?
2) What are they lined by?

Answer 150

1) Oropharynx and laryngopharynx
2) Stratified squamous epithelium

Question 151

1) The larynx, or ____ ____, is a cartilaginous chamber. What is the primary function of the larynx?
2) What is the flap of tissue that guards the opening of the larynx called? What is its purpose?

Answer 151

1) Voice box; to keep food and drink out of the airway and sound production.
2) Epiglottis; closes the airway and directs food to esophagus behind it

Question 152

1) The framework of the larynx consists of how many cartilages?
2) The _________ cartilage, the most superior, is a spoon-shaped supportive plate in the epiglottis.
3) The largest, the _________cartilage, is named for its shield-like shape. It covers the anterior and lateral aspects and forms the “Adam’s apple,” which is larger in males.
4) The ring-like _________ cartilage is located inferior to the thyroid cartilage.

Answer 152

1) 9 cartilages.
2) The epiglottic cartilage, the most superior
3) The largest, the thyroid cartilage
4) The ring-like cricoid cartilage is located inferior to the thyroid cartilage

Question 153

1) What are the two folds located in the larynx?
2) What purpose do they serve?
3) Where is the glottis located?

Answer 153

1) The superior vestibular fold and inferior vocal fold. 2) The vestibular fold plays no role in speech and just closes the larynx during swallowing, and the vocal fold allows for speech.
3) The glottis is the two folds and the space between them

Question 154

1) The __________, or “windpipe,” is a rigid tube anterior to the esophagus. 2) It is supported by 16 to 20 C-shaped rings of __________ cartilage.
3) The open part of the C faces __________.
4) What does the gap in the C allow for?

Answer 154

1) The trachea
2) It is supported by hyaline cartilage.
3) The open part of the C faces the esophagus.
4) The gap in the C allows for the esophagus to expand into the trachea when swallowing food.

Question 155

1) The inner lining of the trachea is what type of tissue?
2) The________ traps inhaled particles, and the upward beating of the __________ moves mucus toward the pharynx, where it is swallowed.

Answer 155

1) Ciliated pseudostratified columnar epithelium.
2) Mucous; Cilia

Question 156

The outermost layer of the trachea, the ______________, is fibrous connective tissue that blends into that of other organs of the mediastinum.

Answer 156

Adventitia

Question 157

1) What does the trachea fork into at its most inferior? The lowermost tracheal cartilage has an internal median ridge called the ________ that directs airflow right and left.
2) The bronchi subdivide in the lungs to form the___________ tree.

Answer 157

1) Carina
2) Bronchial

Question 158

1) The lungs are somewhat conical with a broad, concave base resting on the diaphragm and a blunt peak called the _________ projecting slightly above the clavicle. 2) The mediastinal surface exhibits a slit called the _________ through which the lung receives the main bronchus, blood vessels, lymphatics, and nerves.

Answer 158

1) Blunt peak called the apex
2) The hilum

Question 159

1) Why is the right lung shorter than the left?
2) Why is the left lung, although taller, narrower than the right?

Answer 159

1) The right lung is short to make room for the liver
2) The left lung is narrower to make room for the apex of the heart

Question 160

1) If an object is aspirated, which lung would it lodge in and why?
2) What do we call the indentation on the medial surface of the left lung?

Answer 160

1) An aspirated object would lodge in the right lung because the right bronchiole is more vertical, shorter, and wider.
2) The indentation on the medial surface of the left lung is the cardiac impression

Question 161

1) How many lobes does the right lung have and what fissures separate which lobes?
2) The left lung has only a _______ and ___________ and a single oblique fissure.

Answer 161

1) The right lung has 3 lobes; the horizontal fissure separates the superior and middle lobes, and the oblique fissure separates the middle and inferior lobes.
2) The left lung has only a superior lobe and inferior lobe and a single oblique fissure.

Question 162

The bronchial tree is a branching system of air tubes within each lung; it extends from the main bronchus to about 65,000 _________ __________

Answer 162

terminal bronchioles

Question 163

1) How many branches does the right lung give off?
2) In both lungs, the lobar bronchi branch into ___________ (tertiary) bronchi.
3) The main bronchi are supported, like the trachea, with C-shaped rings of hyaline cartilage, whereas the _________ and ___________ bronchi are supported by overlapping crescent-shaped cartilaginous plates.

Answer 163

1) 3
2) In both lungs, the lobar (secondary) bronchi branch into segmental (tertiary) bronchi.
3) Lobar (secondary) and segmental (tertiary) bronchi are supported by overlapping crescent-shaped cartilaginous plates.

Question 164

1) Does the pulmonary artery carry to the alveoli or away from the alveoli? 2) What does the bronchial artery serve?
3) Is the blood in the bronchial artery oxygenated or deoxygenated?
4) What muscle is located here, skeletal or smooth?

Answer 164

1) To the alveoli
2) Bronchial artery from aorta services bronchial tree with systemic blood
3) Oxygenated blood
4) Smooth muscle

Question 165

What determines when you call a vessel in the bronchial tree bronchioles? Is cartilage here? What does the bronchiole enter?

Answer 165

Bronchioles are 1 mm or less in diameter and have no cartilage support, and each bronchiole enters a Pulmonary lobule

Question 166

1) What is a terminal bronchiole, i.e., when do you change from bronchiole to terminal bronchiole?
2) What branches off a terminal bronchiole? What is considered the beginning of the respiratory zone?

Answer 166

1) Terminal bronchioles have no mucous glands or goblet cells but still have cilia; they’re the final branches of the conducting zone
2) They branch off into respiratory bronchioles, which is the beginning of the respiratory zone.

Question 167

What 3 things are located after the respiratory zone starts?

Answer 167

Respiratory bronchiole, alveolar ducts, and alveolar sacs

Question 168

What is the path of airflow in the conducting division starting with the nasal cavity and ending with the terminal bronchiole?

Answer 168

1) Nasal cavity
2) Nasopharynx
3) Oropharynx
4) Laryngopharynx
5) Larynx
6) Trachea
7) Primary bronchi
8) Secondary bronchi
9) Tertiary bronchi
10) Bronchioles
11) Terminal bronchioles

Question 169

1) How many alveoli are in each lung?

Answer 169

150 million

Question 170

What are the three type of alveoli cells? What are their functions?

Answer 170

1) Squamous (type I) alveolar cells
a) Thin cells that allow for rapid gas diffusion between alveolus and bloodstream
b) Cover 95% of alveolus surface area; most numerous
2) Great (type II) alveolar cells
a) Round to cuboidal cells that cover the remaining 5% of alveolar surface
b) Repair the alveolar epithelium when the squamous (type I) cells are damaged
c) Secrete pulmonary surfactant
3) Alveolar macrophages (dust cells)
a) Wander the lumens of alveoli and the connective tissue between them
b) Keep alveoli free from debris by phagocytizing dust particles
c) 100 million dust cells die each day as they ride up the mucociliary escalator to be swallowed and digested

Question 171

1) What are the most numerous of all cells in the lungs and what do they do?
2) Which alveolar cell type secretes surfactant?
3) Which alveolar cell type helps repair the alveolar epithelium?
4) Which cell type does phagocytosis?

Answer 171

1) Squamous (type I) alveolar cells are the most numerous; they’re thin cells that allow for rapid gas diffusion between alveoli and bloodstream
2) Great (type II) alveolar cells
3) Great (type II) alveolar cells
4) Alveolar macrophages (dust cells)

Question 172

1) What supplies the web of blood capillaries around each alveoli?
2) What makes up the respiratory membrane barrier? What is the barrier between?

Answer 172

1) A pulmonary artery
2) It’s a thin barrier between the alveolar air and blood that consists of squamous alveolar cells, endothelial cells of the blood capillary, their shared basement membrane, and the thin layer of moisture inside the alveolus.

Question 173

1) What happens to keep fluid from accumulating in the alveoli?
2) Why don’t you want fluid to accumulate in the alveoli?

Answer 173

1) Low capillary pressure is maintained to keep low filtration (prevents membrane rupture), excess liquid is absorbed by the blood capillaries, and the lungs have the most extensive lymphatic drainage in the body
2) If fluid accumulates in the alveoli, then gasses diffuse too slowly through liquid to sufficiently aerate the blood

Question 174

1) At the hilum of the lungs, the visceral pleura turns back on itself and forms the ________ pleura.
2) The space between the parietal and visceral pleurae is called the _________ cavity.

Answer 174

1) At the hilum, the visceral pleura turns back on itself and forms the parietal pleura.
2) The space between the parietal and visceral pleurae is called the pleural cavity.

Question 175

What are functions of the pleurae and pleural fluid of the lungs? (3)

Answer 175

1) Reduce friction
2) Create pressure gradient: Lower pressure than atmospheric pressure; allows the two layers to stick to each other (assists lung inflation)
3)Compartmentalization: Prevents spread of infection from one organ to another

Question 176

1) Breathing, or pulmonary ventilation, consists of a repetitive cycle of _________ (inhaling) and ___________ (exhaling).
2) What does a respiratory cycle consist of?
3) What is quiet respiration? What is forced respiration?

Answer 176

1) Inspiration; expiration
2) One complete inspiration (inhaling) and expiration (exhaling)
3) Quiet expiration is a passive process occurring at rest, whereas forced expiration is an active process that occurs during exercise.

Question 177

1) Can you name the muscles of respiration?
2) Which is the prime mover of inhalation? Which are synergist muscles for inhalation?

Answer 177

1) The diaphragm, external intercostals, and scalenes are typically used for respiration
2) The prime mover of inhalation is the diaphragm; the synergists are the external intercostals and scalenes

Question 178

1) Which muscles are used for forced inhalation? 2) Which muscles are used for forced expiration?

Answer 178

1) Forced inhalation: The erector spinae, sternocleidomastoid, pectoralis major, pectoralis minor, and serratus anterior muscles are used 2) Forced expiration: The rectus abdominis and the internal intercostals are used.

Question 179

1) When do you use the Valsalva maneuver?
2) How is the maneuver performed?

Answer 179

1) Used during childbirth, urination, defecation, vomiting
2) Consists of taking a deep breath, holding it by closing the glottis, and then contracting the abdominal muscles to raise abdominal pressure and push organ contents out

Question 180

1) Automatic neural control of breathing requires the VRG and the DRG found in which organ?
2) Which sets the basic respiratory rhythm?

Answer 180

1) The medulla
2) The VRG sets the basic respiratory rhythm of 12 breaths/minute

Question 181

1) Which respiratory group modifies the rate and depth of breathing?
2) Which receives influences from external sources?

Answer 181

1) The DRG modifies the rate and depth of breathing
2) The DRG uses influences from external sources

Question 182

1) The PRG is in what organ?
2) What is the purpose of the PRG?

Answer 182

1) The PRG is in the pons.
2) It modifies rhythm of the VRG by outputs to both the VRG and DRG. It does this to adapt breathing to special circumstances such as sleep, exercise, vocalization, and emotional responses

Question 183

What would be examples of voluntary control of breathing?

Answer 183

Holding your breath, playing an instrument, swimming, etc

Question 184

1) Where are central chemoreceptors located? 2) They respond to changes in which fluid, blood or cerebrospinal fluid? They respond mostly to changes in CO2, O2 or pH?

Answer 184

1) The central chemoreceptors are in the medulla
2) They respond to changes in the pH of cerebrospinal fluid which reflects the CO2 level in the blood. They aren’t sensitive to oxygen levels.

Question 185

1) Where are the peripheral chemoreceptors located? 2) They respond to changes in which fluid, blood or cerebrospinal fluid? They respond mostly to changes in CO2, O2 or pH, some combination of those, all of those or none of those?

Answer 185

1) The peripheral chemoreceptors are in the carotid and aortic bodies
2) They respond to changes in the the O2 and CO2 content and the pH of blood

Question 186

1) What are the purposes of stretch receptors?
2) What would irritant receptors respond to?
3) Voluntary control of breathing involves which lobe of the cerebrum? This is known as a ________________ influence.

Answer 186

1) Stretch receptors are important to the inflation; they cause the (Hering-Breuer) reflex, which prevents over-inflation
2) Irritant receptors respond to smoke, dust, pollen, chemical fumes, cold air, and excess mucus
3) Voluntary control of breathing involves the cerebral cortex; this is known as cortical influences. This part of the cerebrum is called the frontal lobe

Question 187

1) Respiratory flow is very similar to what other flow in the body?
2) If resistance does up, does the flow of air go up or down?
3) Is this inversely proportional or directionally proportional?

Answer 187

1) Blood flow
2) If resistance goes up, airflow goes down.
3) This is inversely proportional.

Question 188

1) What is atmospheric pressure in mmHg and in atm?
2) What does it mean to have positive respiratory pressure? What does it mean to have negative respiratory pressure?

Answer 188

1) 760mmHg or 1atm.
2) Positive respiratory pressure means the respiratory pressure is above that of the atmosphere, and negative respiratory pressure means it’s below atmospheric pressure.

Question 189

1) What does Boyle’s law state?
2) If lung volume increases, what does this do to intrapulmonary pressure? Does it increase or decrease? Does air move into the lungs or out of the lungs?

Answer 189

1) That at a constant temperature, the pressure of a given quantity of gas is inversely proportional to its volume
2) If the volume increases, intrapulmonary pressure decreases, and air moves into the lungs if it falls below atmospheric pressure

Question 190

1) If lung volume decreases, what does this do to intrapulmonary pressure? Does air move into the lungs or out of the lungs?
2) When does air flow stop moving?

Answer 190

1) If the volume decreases, intrapulmonary pressure increases, and air moves out of the lungs.
2) When intrapulmonary pressure is equal to the atmospheric pressure

Question 191

Which profession uses cm of water for pressure unit measurements and why?

Answer 191

Respiratory physiologists because it’s more sensitive than mmHg, since Hg (mercury) is a heavy liquid

Question 192

1) As the thoracic cage expands, the two layers of pleura do what?
2) And what are the two reasons the pleural membranes do the thing they do?
3) Is air flowing in or out of the lungs?

Answer 192

1) The two layers of pleura stick together
2) Because:
a) Cohesion of water in the pleural cavity
b) Slightly negative Intrapleural pressure
-Recoil of lung tissue and tissues of thoracic cage causes lungs and chest wall to be pulling in opposite directions
-About −5 cm H_2 O of intrapleural pressure results
3) Air is flowing into the lungs; elastic coil of the thoracic cage compresses the lungs

Question 193

When the prime mover of inspiration contracts, in what direction does it move? What does this do to the volume in the thoracic cavity?

Answer 193

It moves downward, which increases the volume of the thoracic cavity

Question 194

In quiet breathing, how much is the total volume increased by?

Answer 194

500ml

Question 195

1) What is expiration? Is air flowing in or out of the lungs?
2) What muscles are involved?
3) When the prime mover of inspiration, relaxes, in what direction does it move? What does it do to the volume in the thoracic cavity when it is relaxed?

Answer 195

1) Exhaling; air is moving out of the lungs
2) No muscles are involved in relaxed exhalation, in forced exhalation the internal intercostals and rectus abdominis are involved
3) The prime mover of inspiration moves upwards towards the lungs when it relaxes, which decreases the volume of the thoracic cavity

Question 196

Define pneumothorax, hemothorax and atelectasis

Answer 196

1) Pneumothorax: Thoracic wall is punctured allowing air into pleural cavity
2) Hemothorax: A collection of blood in the space between the chest wall and the lung
3) Atelectasis: Collapse of part or all of a lung

Question 197

1) What happens to airflow if you increase resistance?
2) What two factors influence airway resistance?

Answer 197

1) Increasing resistance decreases airflow
2) Bronchiole diameter and pulmonary compliance

Question 198

1) What is bronchodilation; what hormones are involved and what happens to airflow?
2) What is bronchoconstriction; what hormones are involved and what happens to airflow?

Answer 198

1) Dilation of bronchiole diameter; controlled by epinephrine and sympathetic stimulation. Increases airflow.
2) Constriction of bronchiole diameter; controlled by histamine, parasympathetic nerves, cold air, and chemical irritants

Question 199

1) What is pulmonary compliance?
2) What are reasons that pulmonary compliance be reduced?

Answer 199

1) The ease with which the lungs or thoracic wall can expand
2) Degenerative lung diseases (TB, black lung disease) that cause scar tissue or increased surface tension due to lack of surfactant

Question 200

What is the purpose of surfactant?

Answer 200

Surfactant disrupts hydrogen bonds between water molecules and thus reduces the surface tension; reducing surface tension increases compliance

Question 201

What is the difference between anatomic dead space and physiologic (total) dead space?

Answer 201

1) Anatomic dead space is the dead space taken up by the conducting zone of the airway; can be altered somewhat by sympathetic and parasympathetic stimulation (sympathetic dilation increases dead space but allows greater flow)
2) Physiologic (total) dead space is the sum of anatomic dead space and any pathological alveolar dead space

Question 202

Give the definitions and the respiratory volumes of the following:
1) Tidal volume
2) Inspiratory reserve volume
3) Expiratory reserve volume
4) Residual volume.

Answer 202

1) Tidal volume: The volume of one breath inhaled or exhaled. ~500ml/breath.
2) Inspiratory reserve volume: The amount of air that can be forcefully inhaled after a normal tidal volume inhalation (3,000ml)
3) Expiratory reserve volume: The amount of air that can be forcefully exhaled after a normal tidal volume exhalation (1,200ml)
4) Residual volume: The amount of air remaining in the lungs after maximum exhalation (1300ml)

Question 203

1) What is a spirometer?
2) What is vital capacity? 3) Do males or females have greater vital capacity?

Answer 203

1) A device that measures rate and depth of breathing, speed of expiration, and rate of oxygen consumption
2) The maximum amount of air that can be exhaled after maximum inspiration (4700ml); decreases with age
3) Males have a higher vital capacity

Question 204

Define:
1) Eupnea
2) Apnea
3) Hyperventilation
4) Hypoventilation

Answer 204

1) Eupnea: relaxed, quiet breathing
2) Apnea: temporary cessation of breathing
3) Hyperventilation: increased pulmonary ventilation in excess of metabolic demand
4) Hypoventilation: reduced pulmonary ventilation leading to an increase in blood CO2

Question 205

Relaxed, quiet breathing, or eupnea, is typically characterized by a TV of _____ mL and a respiratory rate of ___ to ____ breaths/min.

Answer 205

500; 12-15

Question 206

1) What is air is composed of?
2) What is the most abundant gas in the atmosphere?
3) The total atmospheric pressure is a sum of?

Answer 206

1) 78.6% nitrogen, 20.9% oxygen, 0.04% carbon dioxide, 0% to 4% water vapor, depending on temperature and humidity, and minor gasses argon, neon, helium, methane, and ozone
2) Nitrogen
3) The contributions of the individual gasses

Question 207

1) What is partial pressure?
2) How do you calculate it?

Answer 207

1) Partial pressure is the separate contribution of each gas in a mixture toward pressure.
1) Percent of mixture x total pressure = partial pressure.

Question 208

What is Dalton’s law?

Answer 208

Total atmospheric pressure is the sum of the contributions of the individual gasses

Question 209

1) What is alveolar gas exchange?
2) Each gas diffuses ______ its pressure gradient until the partial pressure of each gas in the air is equal to its partial pressure in the water, namely the water film on the surface of alveoli.

Answer 209

1) Alveolar gas exchange is the swapping of O2 and CO2 across the respiratory membrane
2) down

Question 210

1) Explain what it means to load oxygen or unload carbon dioxide?
2) Do respiratory gasses come in contact with water?

Answer 210

1) It means oxygen is entering the blood and carbon dioxide is leaving it.
2) Yes; there is a film of water on the outside of the alveolar films.

Question 211

1) When does a gas stop diffusing down its partial pressure gradient?
2) What does Henry’s law state?

Answer 211

1) Until the partial pressure of each gas in the air is equal to its partial pressure in water
2) For a given temperature, the amount of gas that dissolves in water is determined by its solubility in water and its partial pressure in air

Question 212

1) Which is more soluble, CO2 or O2?
2) What gas is mostly insoluble in plasma?

Answer 212

1) CO2 is 20 times more soluble than O2
2) N2 is practically insoluble in plasma

Question 213

The greater the PO2 in alveolar air, the _______ O2 the blood picks up; and the greater the PCO2 in the blood, the ______ CO2 is released into alveolar air.

Answer 213

more; more

Question 214

In gas exchange, as partial pressure are different, is the amount of O2 and CO2 exchanged, the same or different and why?

Answer 214

Equal amounts of O2 and CO2 are exchanged, since the CO2 gradient might not be as steep as the oxygen gradient, but it’s more soluble.

Question 215

List the four factors that can change the rate of gas exchange and describe them

Answer 215

1) Pressure gradient: increased pressure gradient between alveoli and blood increases rate of gas exchange
2) Respiratory membrane surface area: decreased surface area decreases the rate of gas exchange
3) Respiratory membrane thickness: increased respiratory membrane thickness decreases the rate of gas exchange
4) Ventilation-perfusion coupling: the ability to match air flow and blood flow to each other

Question 216

1) What are reasons that could result in decreased lung surface area?
2) What are reasons the membrane thickens?

Answer 216

1) Emphysema, lung cancer, and tuberculosis decrease surface area for gas exchange
2) Pneumonia, pulmonary edema (left ventricular heart failure), etc. can cause the membrane to thicken

Question 217

Which term ventilation or perfusion refers to the alveolus? Which term ventilation or perfusion refers to the capillaries?

Answer 217

Ventilation refers to the alveolus, perfusion refers to the capillaries

Question 218

1) What is necessary for good gas exchange?
2) Poor ventilation causes local ___________ of the pulmonary arteries, redirecting blood to better-ventilated alveoli.
3) Good ventilation stimulates ________ of the arteries and increases perfusion so that most blood is directed to regions where it can pick up the most oxygen.
4) This is the opposite from the reactions of systemic arteries, where oxygen deficiency causes ___________.

Answer 218

1) Gas exchange requires both good ventilation of alveolus and good perfusion of the capillaries
2) Constriction
3) Dilation
4) Perfusion

Question 219

1) What is the number one way oxygen is transported in the body?
2) Define:
a) Oxyhemoglobin
b) Deoxyhemoglobin
c) Carbaminohemoglobin

Answer 219

1) Bound to hemoglobin
2a) Oxyhemoglobin (HbO2): O2 bound to hemoglobin
2b) Deoxyhemoglobin (HHb): hemoglobin with no O2
2c) Carbaminohemoglobin (HbCO2): hemoglobin with CO2

Question 220

1) How many molecules of oxygen can bind to one hemoglobin?
2) What percent of bound oxygen is unloaded in the tissues?
3) Why is carbon monoxide poisonous?

Answer 220

1) 4 molecules of O2
2) 25% is unloaded in the tissues
3) If hemoglobin is given a choice between binding to oxygen or carbon monoxide, it will bind to carbon monoxide every single time

Question 221

1) What are the three forms carbon dioxide is found in the body?
2) In the transport of CO2 and in exchange of CO2, the majority is in the form of what acid?

Answer 221

1) Most is carbonic acid, some is carbaminohemoglobin, some as dissolved gas
2) Carbonic acid

Question 222

Write out and interpret the carbon dioxide plus water reaction through dissociation into bicarbonate and free hydrogen

Answer 222

1) CO2 + H2O&raquo_space; H2CO3&raquo_space; HCO3- + H+.
2) Carbon dioxide plus water can lead to the formation of carbonic acid, which can then dissociate into bicarbonate and free hydrogen.

Question 223

1) In CO2 loading, is CO2 diffusing into cells or diffusing into blood?
2) What enzyme catalyzes the reaction?
3) Explain how the chloride shift is working. What is being exchanged for chloride?

Answer 223

1) CO2 is diffusing into the blood
2) Then carbonic anhydrase from the RBC catalyzes the reaction of carbon dioxide and water into carbonic acid, which then disassociates into bicarbonate and free hydrogen.
3) Then hydrogen bonds to hemoglobin, making it release O2, bicarbonate diffuses out of the RBC and is exchanged for chloride (chloride shift)

Question 224

1) In CO2 unloading, what is loading onto the Hb as CO2 is dissociating?
2) Explain how the reverse chloride shift is working. What is being exchanged for chloride?

Answer 224

1) As hemoglobin loads O2, its affinity for H+ decreases, so H+ dissociates from hemoglobin and binds with bicarbonate.
2) Then bicarbonate diffuses back into RBC to be exchanged for Cl−, free CO2, that is generated and diffused into alveolus to be exhaled

Question 225

What are the factors that adjust the rate of oxygen unloading to meet the body’s needs?

Answer 225

1) Ambient PO2: active tissue has a decreased pressure of oxygen, so oxygen is released from Hb
2) Ambient pH (Bohr effect): active tissue has an increased amount of CO2, which lowers pH of blood; promoting O2 unloading
3) Temperature: Active tissue has an increase temp; promotes O2 unloading

Question 226

1) What is the range of blood pH?
2) What is the most potent stimulus for breathing? What is the second most potent stimulus for breathing? What is the last most potent stimulus for breathing?

Answer 226

1) 7.35-7.45
2) Most important is pH, followed by CO2, and least significant is O2

Question 227

1) What is used to maintain the pH of the brain?
2) Central chemoreceptors are located in what organ and what fluid do they monitor?
3) Peripheral chemoreceptors monitor what fluid?
4) Which produces most of the response?

Answer 227

1) The adjustment of pulmonary ventilation (breathing)
2) Central chemoreceptors are in the medulla; monitor CSF
3) Peripheral chemoreceptors; monitor blood
4) Central chemoreceptors produce 75% of the response

Question 228

Define acidosis, alkalosis, hypocapnia and hypercapnia. Relate hypocapnia and hypercapnia with acidosis and alkalosis.

Answer 228

1) Acidosis: blood pH lower than 7.35
2) Alkalosis: blood pH higher than 7.45
3) Hypocapnia: PCO2 less than 37 mm Hg (normal 37 to 43 mm Hg)
-Most common cause of alkalosis
4) Hypercapnia: PCO2 greater than 43 mm Hg
-Most common cause of acidosis

Question 229

1) When is a respiratory imbalance considered respiratory acidosis? What is happening to CO2 and what is happening to the pH number?
2) Would hypoventilation or hyperventilation be the correct corrective function?

Answer 229

1) When here’s a pH imbalance (low pH) resulting from a mismatch between the rate of pulmonary ventilation and the rate of CO2 production; there is too much CO2 produced, so pH goes down.
2) Hyperventilation would be the corrective function

Question 230

1) When is a respiratory imbalance considered respiratory alkalosis? What is happening to CO2 and what is happening to the pH number?
2) Would hypoventilation or hyperventilation be the correct corrective function?

Answer 230

1) A pH imbalance (high pH) resulting from a mismatch between the rate of pulmonary ventilation and the rate of CO2 production; there is too little CO2 produced, so pH goes up.
2) Hypoventilation would be the corrective function

Question 231

1) What is hypoxic drive? 2) What are situations that could cause this to occur?

Answer 231

1) Respiration driven more by low PO2 than by CO2 or pH
2) Emphysema, pneumonia, or high elevations after several days

Question 232

1) Define COPD.
2) What are the two major COPDs?
3) What is the most common habit associated with COPD?

Answer 232

1) Long-term obstruction of airflow and substantial reduction in pulmonary ventilation
2) Chronic bronchitis and emphysema
3) Smoking

Question 233

1) What are symptoms of chronic bronchitis?
2) What are symptoms of emphysema?
Consider: Which reduces surface area? Which results in chronic inflammation and infections?

Answer 233

1) Chronic bronchitis: Hypoxemia and cyanosis; severe, persistent inflammation of lower respiratory tract; excessive mucus produced, develops into a chronic cough
2) Emphysema: Alveolar walls break down reducing surface area, which makes lungs fibrotic and less elastic. Air passages collapse (obstructs outflow of air), which causes air to be trapped in lungs, so the person becomes barrel-chested. Weakens thoracic muscles and takes 3-4x the amount of energy just to breathe

Question 234

1) What does COPD due to vital capacity?
2) What are other symptoms that COPD causes?

Answer 234

1) It reduces vital capacity
2) It causes hypoxemia, hypercapnia, and respiratory acidosis
Hypoxemia stimulates erythropoietin release from kidneys, and leads to polycythemia

Question 235

What is Cor pulmonale?

Answer 235

Hypertrophy and potential failure of right heart due to obstruction of pulmonary circulation

Question 236

1) What cancer accounts for more deaths than any other form of cancer?
2) What is the cause of people getting this type of cancer?
3) How many carcinogenic compounds are in cigarette smoke?

Answer 236

1) Lung cancer
2) Smoking
3) At least 60