Exam 1 Study Guide Flashcards
All cells, no matter what they do, are made of the same 4 building blocks:
carbohydrates, proteins, lipids, nucleic acids
Proteins consist of:
chain of amino acids
Nucleic acids provide
instructions for making proteins
Describe a catabolic reaction
hydrolysis of complex structures to simpler ones; aka breaking down reactions
Describe anabolic reactions
synthesis of large molecules from small ones; aka building reactions; ex: amino acids creating protein
What is cellular respiration?
catabolism of food fuels to the capture of energy to form ATP in cells;
What are the three processes of cellular respiration?
glycolysis
krebs cycle
oxidative phosphorylation
Describe glycolysis
-Input: glucose
-anaerobic
-occurs within cytosol
-used for quick energy(ie: pasta before race)
-FINAL PRODUCTS: 2 pyruvic acids, 2 NADH, 2 ATP
Describe the Krebs cycle
-occurs in mitochondrial matrix
-output of pyruvic acid from glycolysis and oxygen are the input for krebs cycle
-produces NADH and FADH for electron donors to drive oxidative phosphorylation
-FINAL PRODUCTS: 8 NADH , 2 FADH, 6 CO2, 2 ATP
Describe oxidative phosphorylation
-directly uses oxygen
-NADH and FADH deliver H+ atoms that combine with oxygen(final electron acceptor)to form water
-pumped H+ creates proton gradient(negative inside, positive outside),
-H+ is attracted to negative matrix inside membrane & diffuses back to matrix via ATP synthesis
What are the inputs and outputs for oxidative phosphorylation?
INPUTS: NADH & FADH(from glycolysis and Krebs cycle are electron donors, Oxygen as final electron acceptor creating water
OUTPUTS: ATP and H2O
Describe the absorptive state.
-anabolism exceeds catabolism
-nutrients pools coming in through food and building up stuff
-when there is food in stomach
-primarily controlled by insulin
Describe the post absorptive state.
-breaking down glycogen
-running on stored material
-Goal: maintain blood glucose between meals
What are the sources of blood glucose?
- glycogenolysis in liver
- glycogenolysis in skeletal muscle
- lipolysis in adipose tissues and liver
- catabolism of cellular protein
How is extra glucose stored?
-triglyceride synthesis
-glucose is easily converted to fat
Describe high density lipoproteins(HDLs)
-highest protein content
-H for healthy
-transfer excess cholesterol to liver to be broken down
Describe low density lipoproteins(LDLs)
-cholesterol rich
-L for lousy
-transport cholesterol to peripheral tissues for membranes, storage, etc
Describe body temperature
-body temp. reflects balance between heat production and heat loss
-core has highest temperature
-shell(skin) has lowest temperature
-regulated by nervous system
What are the four mechanisms of heat transfer?
- radiation: loss of heat by infrared rays
- conduction: transfer of heat by direct contact
- convection: transfer of heat to surrounding air
- evaporation: heat loss due to evaporation of water from body surfaces; aka sweating
What is insensible heat loss?
heat loss by simply existing
What is sensible heat loss?
when body temperature rises and sweating increases water vaporization
The endocrine system…
dumps hormones into the blood from the endocrine glands.
What are target cells?
tissues with receptors for specific hormone; if it has a receptor, it is a target cell
Can water soluble hormones enter the cell?
No, they bind to the plasma membrane and affect the target cell by triggering chain reactions inside cell; ex: hormones
Can lipid soluble hormones enter the cell?
Yes, lipid soluble hormones bind to DNA and directly activate genes; ex: steroid hormones
What is a gene?
DNA sequence that encodes a protein; all cells in the body have the same DNA
What controls hormones release by endocrine glands?
endocrine glands are stimulated to synthesize and release hormones in response to different stimuli
What are the three stimuli that stimulate endocrine glands?
-humoral stimuli
-neural stimuli
-hormonal stimuli
Humoral stimuli
changing blood levels of ions and nutrients stimulate secretion of hormones; aka: what’s going on in the blood?
Neural stimuli
nerve fibers stimulate hormone release; nervous system; ex: fight or flight stress response
Hormonal stimuli
hormones stimulate other endocrine organs to release their hormones; hormones bind to receive feedback mechanisms
Why do the electron transport chain complexes pump protons?
to create the electrochemical proton gradient
Endocrine glands secrete __________, which are recognized only by their ______ cells.
hormones; target
How do hormones work?
Hormones circulate in the blood, and only cells with receptors for that hormone are affected.
Hormones act at receptors in two ways:
- water soluble hormones
- lipid soluble hormones
What are second messengers?
intracellular chemical signals that connect plasma membrane events to internal metabolic machinery of cell
What are the two major lobes of the pituitary gland?
posterior pituitary lobe and anterior pituitary lobe
Describe the posterior pituitary lobe
contains neural tissue, stores hormones made by hypothalamus, which are oxytocin and antidiuretic hormone(ADH)
Describe the anterior pituitary lobe
-contain glandular tissue, makes hormones: GH, TSH, ACTH, FSH, LH, PRL
Where are the pituitary lobes located?
base of brain below hypothalamus(derived from hypothalamus)
All pituitary hormones activate…
cyclic AMP second messenger systems except GH
What is a result of antidiuretic hormone?
makes you retain water in body
Antidiuretic hormone is also called
vasopressin
What are the two posterior pituitary hormones?
oxytocin and antidiuretic hormone(ADH)
What are the six hormones produced in the anterior pituitary lobe
-growth hormones(GH)
-thyroid stimulating hormone(TSH)
-adrenocorticotropic hormone(ACTH)
-follicle stimulating hormone(FSH)
-luteinizing hormone(LH)
-prolactin(PRL)
Describe the pancreas
triangular typically behind stomach; has both exocrine and endocrine cells
-contains acinar cells and pancreatic islets
What are acinar cells?
Exocrine cells that produce enzyme rich juice for digestion
What are pancreatic islets?
contain endocrine cells(alpha and beta)
Alpha cells produce ________.
glucagon(puts glucose in blood
Beta cells produce _______.
insulin(stimulates cells to take glucose out of blood)
Insulin and glucagon from the _______ regulate ______ ______ levels.
pancreas; blood glucose
________ stimulates pancreas to secrete more insulin. Activated by insulin
Osteocalcin
What does insulin do and where does it come from?
from pancreas; activates glucose to be taken out of blood to be used for skeletal muscle(or anything needed); also enhances membrane transport of glucose into fat and muscle cells
What stimulates insulin secretion?
-elevated blood levels of glucose and amino acids
-intestinal GIP and parasympathetic stimulation
The absorptive state is primarily controlled by
insulin
Diabetes mellitus is caused by
inadequate insulin production or abnormal insulin receptors
Insulin triggers enzymes to
catalyze oxidation of glucose for ATP production-first priority
What is the primary stimulus of insulin?
elevated blood glucose levels
Type 1 diabetes is due to
the pancreas not making enough insulin
Type 2 diabetes is due to
insulin resistance
Describe leptin
hormone used for appetite control
Describe resistin
insulin antagonist
Describe adiponectin
enhances sensitivity to insulin
What is an example of a second messenger?
cAMP
Do lipid soluble hormones have receptors?
Yes, they have receptors in nucleus, thus binding to the DNA
Where are oxytocin and ADH produced and secreted?
produced and by posterior pituitary lobe
How are oxytocin and ADH similar in composition, yet different in function?
they have nearly identical molecular composition, but oxytocin is a strong stimulant of uterine contraction, while ADH prevents urine formation
What is thyroid hormone made from?
T4 and T3; thyroid affect every cell in body; major metabolic hormone
What is hematocrit?
the percent of blood volume that is RBCs
What are erythrocytes?
red blood cells; biconcave discs with no organelles; full of hemoglobin
What are the formed elements that make up blood?
erythrocytes, leukocytes, and platelets
Hematopoietic stem cells can only turn into
blood cells
Heme is
pigment bonded to each globin chain that gives blood red color
Hemoglobin is
the bus for O2; binds reversible with oxygen
High oxygen in blood causes
scarlet colored blood
Low oxygen in blood causes
dark red blood
Erythropoiesis is
red blood cell production
Erythropoietin signals the
production of red blood cells
Too few RBCs leads to
hypoxia
Too many RBCs causes
increased blood viscosity
Platelets are _____ _________ used for ______ _________.
cell fragments; blood clotting
Platelets are derived from
megakaryoblasts
Platelets stick to _______ ______ via plasma protein.
collagen fibers
Hemostasis is
a series of reactions to stop bleeding
What are the three steps to hemostasis?
- vascular spasm(restricts blood flow)
- platelet plug formation(adhere to collagen fibers)
- coagulation(clot)
Thromboembolic disorder causes
undesired clot formation
Bleeding disorders cause
abnormalities that prevent normal clot formation
What is fibrinogen?
4% of plasma proteins; produced by liver; forms fibrin threads of blood clot
Describe fibrin
causes plasma to become gel like trap for formed elements; used to form structural basis of clot
Thrombin strings _________ to make _____ mesh.
fibrinogen; fibrin
Prothrombin(inactive) is cut to form _______
thrombin(active)
No prothrombin=
no clotting
Plasmin is a
fibrin digesting enzyme
Antigens of ABO and Rh blood groups cause
transfusion reactions
What blood type is known as the universal donor?
O
What blood type is known as the universal recipient?
AB
Blood type B can only receive blood type __?
B and O
Blood type A can only receive blood type __?
A and O
Blood type O has what antibodies?
anti a and anti b
Blood is composed of
plasma, Buffy coat, and erythrocytes
The Buffy coat contains
leukocytes(WBCs) and platelets
Which blood cells are considered the only complete cells?
white blood cells
Red blood cells are dedicated to
respiratory gas transport
White blood cells are used to
preventing infection; immune defense
Leukocytosis is
the high WBC count over 11,000(normal response to infection)
Leukocytes can leave capillaries via
diapedesis
Diapedesis is
leaving blood stream to migrate to sight of wound looking to defend
What are the types of leukocytes based on abundance in blood
- neutrophils
- lymphocytes
- monocytes
- eosinophils
- basophils
T cells and B cells…
mediate immunity
What is plasma?
non living fluid matrix that suspends the formed elements
Most blood cells originate in the
red bone marrow
Why is iron important in the blood?
necessary for erythropoiesis
What type of blood can someone with type O receive?
O, bc they have A and B antibodies
Why do patients with leukemia frequently have anemia and bleeding problems?
Those w leukemia have an overproduction of WBCs rather than RBCs and platelets.
Anemia is the cause of
abnormally low O2 carrying capacity
