Systems of the Body Flashcards
1
Q
What are the key parts of a neuron and their functions?
A
- Cell body: source of life for the cell
- Dendrites: receive messages from other neurons
- Axon: carries messages away from the cell
- Synaptic knobs: send messages to other neurons
- Synapse: gap between neurons for signal transmission
2
Q
What are the main divisions of the nervous system?
A
- CNS: brain and spinal cord
- PNS: somatic (controls voluntary movements) and autonomic (regulates involtunary functions such as the regulation of internal organs and smooth muscles) systems
3
Q
What are the key parts of the hindbrain and midbrain, and what are their functions?
A
- Hindbrain:
Medulla: Receives sensory info from the heart
Pons: Links hindbrain and midbrain
Cerebellum: Coordinates voluntary muscle movements - Midbrain: Pathway for sensory and motor impulses
4
Q
What are the two main sections of the forebrain, and what are their functions?
A
- Diencephalon:
Thalamus: Relays sensory stimuli
Hypothalamus: Regulates heart rate and blood pressure - Telencephalon: Includes the two cerebral hemispheres
5
Q
What are the key parts of the limbic system and their functions?
A
- Amygdala: Detects threats
- Hippocampus: Stores emotional memories
- Cingulate gyrus, septum, and hypothalamus: Involved in emotional functioning
6
Q
What are neurotransmitters and catecholamines?
A
- Neurotransmitters: Chemicals that regulate nervous system function
- Catecholamines: Epinephrine and norepinephrine promote sympathetic NS activity and are released during stress
7
Q
What is the role of the spinal cord and the difference between efferent and afferent nerves?
A
- Spinal cord: Transmits messages between brain and body
- Efferent nerves: Carry signals from brain to muscles (e.g to produce muscle action)
- Afferent nerves: Carry sensory info from body to brain (e.g sensory information)
8
Q
What does the somatic nervous system control?
A
The somatic nervous system controls both sensory and motor functions of the skin and muscles.
9
Q
what are the two divisions of the autonomic nervous system?
A
The autonomic nervous system has two divisions:
1. Sympathetic nervous system: Activates the body for action (“fight or flight”).
- Parasympathetic nervous system: Relaxes the body (“rest and digest”).
10
Q
What regulates the endocrine system and how does it communicate?
A
The endocrine system is regulated by the hypothalamus and pituitary gland and communicates through hormones like adrenaline and cortisol.
11
Q
Where are the adrenal glands located, and what do they do?
A
The adrenal glands are located on top of each kidney. They release hormones in response to emergencies and stress.
Cortisol: Helps control swelling, but high levels over time can cause issues like high blood pressure or ulcers.
Epinephrine & Norepinephrine (adrenaline and noradrenaline): Trigger quick energy responses in the body.
12
Q
What happens during sympathetic nervous system activation?
A
The sympathetic nervous system triggers the release of epinephrine and norepinephrine from the adrenal glands, increasing heart rate and blood pressure.
13
Q
How does the HPA axis respond to stress, and what are its impacts on the body?
A
The HPA axis is activated during stress, leading the pituitary gland to release ACTH, which stimulates the adrenal glands to produce cortisol.
- Prolonged activation can lead to allostatic load and weaken the immune system.
14
Q
Where is the thyroid gland located, and what does it do?
A
The thyroid gland is located in the neck and produces thyroxin, a hormone that regulates activity levels and growth.
15
Q
What are hypothyroidism and hyperthyroidism?
A
- Hypothyroidism: Too little thyroid hormone, leading to low energy and weight gain.
- Hyperthyroidism: Too much thyroid hormone, leading to high energy, weight loss, and trouble sleeping.
16
Q
Where is the pancreas located, and what does it do?
A
The pancreas is located below the stomach and regulates blood sugar levels by producing insulin, which helps the body absorb blood sugar.
17
Q
Why does high blood sugar make it difficult to lose weight?
A
When blood sugar is high, the body uses glucose for energy instead of burning fat. The body only burns fat when blood sugar levels drop low enough.
18
Q
What is diabetes, and what are the differences between Type I and Type II diabetes? When do they usually occur?
A
Diabetes occurs when the body cannot produce or use insulin properly.
- Type I diabetes: The body cannot produce insulin and is insulin-dependent.
- Type II diabetes: The body doesn’t produce enough insulin or becomes insensitive to it
19
Q
What are the main functions of the mouth, stomach, small intestine, and large intestine in digestion?
A
- Mouth: Breaks food down with the help of salivary glands
- Stomach: Starts protein digestion by liquefying and mixing food.
- Small Intestine: Responsible for chemical breakdown and nutrient absorption.
- Large Intestine: Absorbs water and stores waste for excretion.
20
Q
What role do enzymes and the esophagus play in digestion?
A
Enzymes break down food substances, and the esophagus pushes food to the stomach using peristalsis.
21
Q
What are some common disorders of the digestive system?
A
- Peptic Ulcers: Sores in stomach or small intestine lining
2.Hepatitis: Inflammation of the liver (caused by viruses or alcohol)
- Cirrhosis: Liver cell death and scarring (due to alcohol or hepatitis)
22
Q
How does the respiratory system function?
A
- The respiratory system moves air in and out of the lungs through mechanical action
- Gas exchange in the alveoli removes CO₂ and brings O₂ into the blood.
- Protective mechanisms like sneezing and coughing help maintain its function.
23
Q
What can happen if the respiratory system’s function is impaired?
A
Impaired function can lead to respiratory conditions such as asthma, bronchitis, and emphysema.
24
Q
Describe the pathway of air through the respiratory system.
A
Air enters through the nose/mouth, passes through the larynx, trachea, bronchial tubes, bronchioles, and finally reaches the alveoli for gas exchange.
25
What are some common disorders of the respiratory system?
1. Asphyxia: Too little oxygen and too much CO₂, common in limited breathing spaces.
2. Anoxia: Oxygen shortage, often occurring at high altitudes, causing confusion and coma.
3. Hyperventilation: Rapid breathing reduces CO₂ levels, leading to dizziness and lightheadedness.
26
What is the function of arteries and veins in the cardiovascular system?
Arteries carry oxygenated blood from the heart to the body, while veins carry deoxygenated blood back to the heart and lungs.
27
How many chambers does the heart have, and what are they called?
The heart has four chambers: the left atrium, right atrium, left ventricle, and right ventricle.
28
What are the functions of the left and right sides of the heart?
The left side pumps oxygenated blood to the body, and the right side pumps deoxygenated blood to the lungs.
29
What is blood pressure?What happens to blood pressure during the systolic and diastolic phases?
- The force of blood pushing against artery walls.
- During the systolic phase, when the heart contracts, BP rises.
- During the diastolic phase, when the heart relaxes, BP is at its lowest.
30
What factors affect blood pressure and how do they influence it? Think of blood pressure like water flowing through a garden hose:
1. Cardiac Output (Water Flow Rate):: More blood pumped = higher BP.
2. Blood Volume (Amount of Water in the Hose: More blood in the body = higher BP.
3. Peripheral Resistance (Hose Narrowing): Narrower arteries = higher BP.
4. Elasticity (Hose Flexibility): Stiffer arteries = higher BP.
5. Viscosity (Thickness of Water):Thicker blood = higher BP
31
What happens to diastolic blood pressure (BP) when arteries dilate?
When arteries dilate, such as in heat, diastolic BP decreases.
32
How does blood pressure fluctuate throughout the day?
Blood pressure follows a daily rhythm, with its lowest point during deep sleep.
33
What factors cause blood pressure to increase?
Blood pressure increases in response to activity, changes in posture, stress, temperature, and increased heart rate or cardiac output.
34
What is atherosclerosis and what causes it?
- Atherosclerosis is the buildup of cholesterol and plaques in arteries, narrowing them
- Associated with poor health habits
35
What is arteriosclerosis and how does it affect blood pressure?
- Arteriosclerosis is the hardening of arteries, often following atherosclerosis.
-As plaques harden, arteries lose their elasticity, leading to increased BP.
36
What are the consequences of atherosclerosis?
Atherosclerosis can cause 1. Angina pectoris (chest pain due to insufficient oxygen)
2. Myocardial infarction (heart attack from blocked blood supply).
37
What is considered high blood pressure in hypertension, specifically regarding systolic and diastolic measurements?
Systolic blood pressure ≥ 140 mmHg
Diastolic blood pressure ≥ 90 mmHg.
38
What is the difference between primary and secondary hypertension?
Primary hypertension has no known cause, while secondary hypertension is due to specific causes like adrenal tumors.
39
What are the two main components of blood?
1. Formed elements
2. Plasma.
40
Formed elements consist of which three elements:
1. Red blood cells
2. Leukocytes (white blood cells)
3. Platlets
41
What is anemia?
Anemia is a condition where there aren’t enough red blood cells or hemoglobin, leading to reduced oxygen delivery to the body.
42
What are the causes of anemia?
1. Iron loss (especially in menstruating women)
2. Inadequate red blood cell production by bone marrow
3. Certain medical conditions affecting red blood cell production
43
What is sickle-cell anemia?
Sickle-cell anemia is a genetic condition that prevents the body from making enough red blood cells.
44
Who is primarily affected by sickle-cell anemia?
Sickle-cell anemia mainly affects people of African, Middle Eastern, Caribbean, and South and Central American descent.
45
What is leukemia?
A condition where too many white blood cells are produced, crowding out red blood cells and plasma, imparing their function
46
What is leukopenia? What diseases is it associated with?
A deficiency of white blood cells and can occur with diseases like TB, measles, and pneumonia.
47
What is leukocytosis?
An excess of white blood cells, often in response to infections like appendicitis and mononucleosis.
48
What is the function of platelets?
Platelets clump together to prevent blood loss by forming clots at injury sites.
49
What is Hemophilia?
A condition where platelets don’t function properly, leading to excessive bleeding from cuts.
50
What are disorders related to clotting involving platelets?
1. Coronary Thrombosis: Clot in the heart arteries
2. Cerebral Thrombosis: Clot in the brain's blood vessels
3. Embolus: Detached clot that can block blood flow, often in the lungs
51
What is plasma composed of?
Plasma is composed of 90% water and 10% plasma proteins and other substances, including hormones, enzymes, waste products, vitamins, sugars, and fatty materials.
52
What are antigens?
Substances (like bacteria, viruses, and fungi) that can trigger an immune response.
53
What are bacteria?
Microorganisms that grow rapidly, compete for nutrients, and can cause illness.
54
What are fungi?
Organisms like mold and yeast that absorb nutrients.
55
What are protozoa?
One-celled animals living in water and insects that can cause diseases when ingested.
56
What are viruses?
Proteins and nucleic acids that take over host cells to replicate.
57
How can transplant success be increased?
By using closely matched genetic tissue and medications that suppress the immune system’s attack on foreign material.
58
What are the four means of infection transmission?
1. Direct Transmission (contact)
2. Indirect Transmission (contaminated surfaces)
3. Biological Transmission: (e.g malaria from mosquitoes)
4. Mechanical Transmission (Pathogens on an organism’s body (e.g., flies landing on food)
59
What are the 4 stages of an infection?
1. Incubation Period: Time between exposure and onset of symptoms
2. Nonspecific Symptoms: General symptoms (e.g., fatigue, fever)
3. Acute Phase: Disease is at its height
4. Recovery or Decline: Resolution of symptoms or worsening of illness
60
What types of infections exist based on location?
1. Localized: Confined to a specific area (e.g., skin infection).
2. Focal: Spreads from one area to others (e.g., dental issue spreading to the jaw).
3. Systemic: Affects the entire body (e.g., sepsis).
61
What are the two main types of immune mechanisms in the body?
1. Nonspecific: General responses to any infection, not tailored to specific pathogens.
2. Specific: Targeted responses acquired after birth that fight specific microorganisms and their toxins.
62
What is phagocytosis?
When certain white blood cells ingest microbes.
63
What is humoral immunity?
Immunity mediated by B lymphocytes, best against bacterial and viral infections.
64
What is cell-mediated immunity?
Immunity involving T lymphocytes, best against fungi, parasites, foreign tissue, and cancer.
65
What do lymphatic and lymphoid organs do?
They deploy lymphocytes to defend the body against foreign material.
66
What are lymph nodes?
Bean-shaped spongy tissues that filter, capture antigens (foreign material) and have compartments for lymphocytes.
67
Where are the largest lymph nodes located?
In the neck, armpit, abdomen, and groin.
68
What is the function of lymph vessels?
They connect to lymph nodes and carry lymph fluid into the bloodstream.
69
What is the function of the spleen in the immune system?
It produces B and T cells and removes old red blood cells.
70
What role do the tonsils play in immunity? Where do they exist?
located in the phraynx: They filter microorganisms that enter the respiratory tract.
71
What is the thymus' role in the immune system?
It helps T cells mature and produces a hormone important for antibodies.
72
What are the main functions of the spleen? Where is it located?
1. Filters antigens from lymph
2. Serves as a home base for white blood cells
3. Removes worn-out red blood cells.
Located: Upper left side of the abdomen
73
What are the two types of phagocytes, and how do they function?
1. Macrophages attach to tissues
2. Monocytes circulate in the blood
Function: Engulf and digesting antigen
74
What do Killer T-cells (CD8) do?
They destroy foreign tissues, cancerous cells, and cells infected by pathogens (invaded by antigens).
75
What is the role of Memory T-cells?
They remember previous antigens to defend against future invasions.
76
Why is it difficult for the immune system to fight cancer?
Cancer cells release substances that suppress the immune response, and some antigens are hard to recognize.
77
What do delayed hypersensitivity T-cells do?
They are involved in delayed immune reactions and produce lymphokines to stimulate other T-cells to grow and attack.
78
What is the role of Helper T-cells (CD4 cells)?
They gather information on invasions and stimulate lymphocytes in the spleen and lymph nodes to attack.
79
What do Suppressor T-cells do?
They slow down or stop immune processes.
80
What are the steps of cell-mediated immunity?
1. Macrophages: Consume pathogens and present antigens.
2. Helper T Cells: Release cytokines to activate immune cells.
3. Killer T Cells: Directly kill infected cells.
4. Memory T Cells: Remember pathogens for quicker responses later.
81
What is the primary action of antibody-mediated immunity?
It attacks antigens while they are still in body fluids, before they invade cells.
82
What are the three main functions of B lymphocytes?
1. Protection against bacteria
2. Neutralizing toxins produced by bacteria
3. Preventing viral infection
4. Produce and secret antibiodies
83
What are antibodies? How do antibodies function in the immune system?
Proteins produced in response to antigens that combine with them to neutralize their toxic effects.
84
What are some lifestyle factors that impair immune functioning?
1. Insufficient vitamins A and E
2. High fat and cholesterol intake
3. Lack of vitamin C
4. Poor sleep
85
How does stress impact the levels of killer T-cells?
Stress lowers the levels of killer T-cells.
86
What effect do adrenaline and cortisol have on the immune system during stress?
1. Adrenaline and cortisol increase suppressor T-cells
2. Decrease helper T-cells
3. Decrease functioning of phagocytes and lymphocytes
87
What are some disorders related to the immune system?
AIDS, cancer, and infectious disorders
88
What are some examples of infectious disorders in relation to the immune system?
1. Splenomegaly: Infection of the spleen.
2. Tonsillitis: Inflammation of the tonsils, affecting their filter function.
3. Mononucleosis:
Enlargement in the lymphatic system.
4. Lymphoma: Tumor in the lymphatic system.
89
How does AIDS affect the immune system?
AIDS kills by destroying helper T-cells (CD4), weakening the immune system and making the body more vulnerable to infections.
90
What is autoimmunity and what role does it play in chronic diseases?
Autoimmunity is when the body's immune system attacks its own tissue, and it can contribute to many chronic diseases.
91
What is diabetes?
Chronic endocrone disorder in which the body cannot produce or use insulin properly.
92
When does Type I diabetes usually occur and what causes it?
Occurrence: Late childhood or early adolescence.
Cause: Caused by an autoimmune reaction, where the immune system attacks insulin-producing beta cells in the pancreas, often following a viral infection
93
When does Type II diabetes usually occur and what causes it?
Occurrence: Typically after age 40.
Cause: Results from a combination of lifestyle factors such as obesity and stress, which lead to insulin resistance.
Over time, the pancreas may fail to produce sufficient insulin.
94
How is nonspecific innate immunity mediated?
1. Anatomical Barriers: Skin acts as the first line of defense.
2. Phagocytosis: Phagocytes engulf and destroy invaders.
3. Antimicrobial Substances: Chemicals like interferon kill microbes.
4. Inflammatory Response: Boosts blood flow and white blood cells, causing redness and swelling.
95
How do humoral and cell-mediated immunity interact?
Humoral immunity, mediated by B cells, produces antibodies that help phagocytes identify pathogens. Cell-mediated immunity involves T cells, which release cytokines to activate phagocytes.
96
What do cytotoxic t-cells do? (T_C cells)
These cells target and destroy virally infected cells by producing toxic substances.
97
What are the effects of the secretion of corticosteroids from the adrenal cortex? "Sustain and Store"
1. Increases protein and fat mobilization
2. Increases access to bodily energy storage
3. Inhibits antibody formation and inflammation
4. Regulates sodium retention
98
What are the effects of the secretion of catecholamines (epinephrine and norepinephrine) from the adrenal medulla? "Fight or flight"
1. Increases heart rate and dilates heart capillaries
2. Increases blood pressure through vasoconstriction
3. Diverts blood to muscle tissue
4. Increases breathing rate
5. Slows down digestion
6. Dilates pupils of the eyes
