FINAL EXAM Flashcards
1
Q
What is the role of the circulatory system?
A
Transports materials around the body
2
Q
What two things do animals need to do?
A
Deliver oxygen and carbon dioxide from all cells of the body
Deliver nutrients to and waste products from all cells of the body
3
Q
How do single-celled organisms compensate for their lack of a circulatory system?
A
They exchange materials directly with the environment
4
Q
How do animals with a single (sponge) or a few cell layers (jellyfish) exchange gases, nutrients, and wastes?
A
Via diffusion
5
Q
What does a circulatory system consist of?
A
Muscular pump (the heart)
Fluid (blood)
Series of conduits (blood vessels)
6
Q
What types of animals use an open circulatory system?
A
Arthropods and mollusks
7
Q
Essentially, how does an open circulatory system work?
A
Fluid leaves the circulatory system and moves between cells
8
Q
Provide the steps that occur in an open circulatory system
A
Heart moves the extracellular fluid (hemolymph) through vessels
Fluid leaves vessels and filters through the tissues; returns to the heart through openings called ostia, which have one-way valves
9
Q
What types of animals use a closed circulatory system?
A
Vertebrates and annelids
10
Q
Essentially, how does a closed circulatory system work?
A
Fluid is contained in a continuous system of vessels
11
Q
Explain the location and movement of blood in a closed circulatory system.
A
Blood is kept separate from interstitial fluid; pumped through the vascular system by one or more hearts. The blood never leaves the vessels
12
Q
What are three advantages of a closed circulatory system?
A
Faster transport of materials through vessels Blood can be directed to specific tissues by varying resistance (diameter of blood vessel) Signaling molecules (hormones) and nutrients can be transported to specific sites
13
Q
How many atria and ventricles are in a 2-chambered fish heart?
A
1 atrium and 1 ventricle
14
Q
How many atria and ventricles are in a 3-chambered heart in amphibians and some reptiles?
A
2 atria and 1 ventricle
15
Q
How many atria and ventricles are in a 4-chambered heart in mammals and some reptiles?
A
2 atria and 2 ventricles
16
Q
What is the role of the atrium?
A
Chambers that receive blood and pass it to a ventricle
17
Q
What is the role of a ventricle?
A
Chambers that pass blood to the lungs or out to the body through arteries
18
Q
What is the order of valves through which blood passes through the heart?
A
Tricuspid…pulmonary…mitral…aortic
19
Q
What is the pericardium?
A
Thin double-layered sac enclosing the heart and containing fluid between the layers to cushion and lubricate the heart
20
Q
What is pericarditis?
A
Inflammation of the pericardium due to viral or bacterial infection
21
Q
What two things are required for circulation?
A
A muscular pump (the heart) and a system of vessels to carry fluid
22
Q
What three classes of vessels are needed for circulation?
A
Need vessels going away from the heart: arteries (large) and arterioles (smaller)
Need vessels for gas and fluid exchange: capillaries, also connect arteries to veins
Need vessels going back to the heart: veins (large) and venules (smaller)
23
Q
What is the order in which vessels carry fluid?
A
Artery…arteriole…capillary…venules…vein
24
Q
What are the two circulatory circuits?
A
Pulmonary and systemic
25
Explain bloodflow in a pulmonary circuit
Deoxygenated blood pumped from RV to lungs
Gases exchanged in lung capillaries
Return to heart: LA
26
Explain bloodflow in a systemic circuit
Oxygenated blood pumped from LV to tissues
Gasses exchanged in tissue capillaries
Return to heart: RA
27
What is atherosclerosis?
"Hardening of the arteries"
28
In atherosclerosis, how is the endothelial lining of arteries damaged?
High blood pressure, smoking, high-fat diet, or microorganisms
29
In regards to atherosclerosis, what is plaque?
A buildup of cholesterol, calcium, and other substances which forms at damage sites
30
After plaque builds up at a damage site, how do artery walls harden?
Fibrous connective tissue made by the invading smooth muscle cells make the artery wall less elastic
31
What does the growing plaque deposit do?
Narrows the artery and causes turbulence in the blood flow
32
What is the role of coronary arteries?
Supply blood to the heart muscle
33
Explain atherosclerosis in coronary arteries
Reduces blood flow; marked by chest pain and shortness of breath
34
What is coronary thrombosis?
A thrombus that forms in the coronary artery can lead to a blockage of blood flow and a heart attack, or myocardial infarction
35
What is an embolus?
A piece of thrombus that breaks loose and can cause an embolism (blockage) if it lodges in a smaller blood vessel
36
What places are likely for an embolism to occur?
Arteries narrowed by plaque
37
What happens if an embolism is in the brain?
Cells fed by that artery will die and cause a stroke
38
What are the 5 risk factors for atherosclerosis?
Genetic predisposition
Age
Environmental factors: high-fat diet, smoking, sedentary lifestyle
Medical conditions: hypertension, obesity, diabetes
39
Explain pressure in the arteries
High pressure, large pulse pressure
40
Explain pressure in the capillaries
Lower pressure, constant flow
41
Explain pressure in the veins
Lowest pressure
42
Explain venous return
Contraction pressure from the heart is not sufficient to move blood, so we have:
1. Skeletal muscle contraction
2. One-way valves in veins to prevent backflow
43
What causes varicose veins?
Damaged venous valves
44
Explain blood flow in the vasculature in detail
1. Blood flow leaves the heart through large arteries and into smaller arterioles
2. Blood from arterioles enters capillaries where gasses and fluid are exchanged
3. From capillaries, blood flows into small venules, which lead to larger vessels, veins
4. Veins carry blood back to the heart
45
Give the general path of blood flow in the vasculature
Artery...arteriole...capillary...venules...vein
46
What is the composition of arteries and arterioles?
Endothelium: single layer of endothelial cells
Two layers of elastic fibers (flexibility)
Thick smooth muscle
Connective tissue
47
What are the three characteristics of arteries and arterioles?
Arteries have more elastic fibers in their walls than other blood vessels (structural support and flexibility)
Contraction of the smooth muscle layer of arterioles results in vasoconstriction, decreases blood flow
Relaxation of the smooth muscle layer results in vasodilation, increases blood blow
48
How much of the human vasculature is composed of capillaries?
80%
49
Every cell of the body of within how many micrometers of a capillary?
100 micrometers
50
Explain the structure of capillaries.
Very thin and slow blood flow; allows for exchange of gases and fluid
51
In what sense are continuous capillaries "continuous"?
Continuous in the sense that the endothelial cells provide an uninterrupted lining
52
Explain the role of continuous capillaries.
Allow smaller molecules like water and ions to pass through intercellular clefts
These capillaries are a constituent of the blood-brain barrier; protects the brain from circulating pathogens
53
Explain fenestrated capillaries
Have small pores in the endothelial cells that allow small molecules and limited amounts of protein to diffuse
54
Where are fenestrated capillaries located?
Intestines, pancreas, kidney
55
What are the structural characteristics of sinusoidal capillaries?
Have larger openings in the endothlium
56
What is the role of sinusoidal capillaries?
Allow red and white blood cells and proteins to pass, aided by an incomplete basement membrane
57
Where are sinusoid blood vessels located?
Bone marrow, lymph nodes, liver, spleen
58
Generally speaking, where are sinusoid capillaries utilized?
Areas where greater movement of cells and materials is necessary
59
What is the composition of veins and venules?
```
Endothelium
1 layer of elastic fibers
Smooth muscle
Connective tissue
Valves to prevent backflow
```
60
What are the characteristics of veins and venules?
Thinner layer of smooth muscle compared to arteries
| Venous pump helps return blood to the heart (skeletal muscle contractions, one-way valves)
61
How do pre-capillary sphincters selectively regulate blood flow?
The body can direct more blood flow to the muscles and organs in times of need (fight or flight), or more blood flow to the intestines during digestion
62
Explain mammalian lung and gas exchange
Bronchi and bronchioles lead to alveoli, the actual site of gas exchange in the lungs
63
In one word, describe plasma's capacity to carry oxygen
Limited
64
What is hemoglobin?
An oxygen carrier in vertebrates; increases oxygen solubility 50-70x
65
Explain the composition of hemoglobin
```
2 alpha-globin peptide chains
2 beta-globin peptide chains
Each has a heme group
Iron atom in heme binds oxygen reversibly
Overall, 4 polypeptide chains
```
66
Explain hemoglobin oxygen binding properties at lung capillaries
Carbon dioxide diffuses out, oxygen diffuses in at alveoli
| High oxygen leads to oxygen binding
67
Explain hemoglobin oxygen binding properties at tissue capillaries
Carbon dioxide diffuses in and oxygen diffuses out
| Low oxygen leads to oxygen release
68
Break down the percent composition of carbon dioxide in the blood
8% carbon dioxide dissolved in liquid component of blood (plasma)
20% bound to hemoglobin
72% carries (dissociated in red blood cells)...carbon dioxide diffuses out of the tissues into blood and red blood cells, carbon dioxide diffuses out of blood in lung
69
Explain plants' classification as autotrophs
Plants use carbon dioxide during the light-independent reactions of photosynthesis to produce carbohydrates
70
Explain gas, mineral and water exchange in plants
Carbon dioxide gas is exchanged along with oxygen and water in leaves. Minerals and water are taken up by roots
71
What are the two parts of uptake and transport in plants?
Water and minerals are transported from roots to branches and leaves
Sugars are transported from the leaves to roots or other areas in need of energy
72
What are the two types of conducting tissue in plants?
Xylem and phloem
73
What is the xylem?
Dead tissue that conducts water and minerals from soil to photosynthetic areas; must flow from roots to highest branches
74
What is the phloem?
Live tissue that transports sugars from photosynthetic areas to the rest of the plant
75
What is osmosis?
Water moves from areas of higher water concentration to areas of lower water concentration
76
What does solute potential measure?
The osmotic strength of a solution
77
What is the solute potential of pure water?
0
78
What happens to solute potential when solutes are added?
Lower solute potential
79
What can solute potential be used to predict?
Water movement in osmosis
80
Plants have ion pumps; what type of transport is this?
Active transport
81
How do ion pumps affect solute potential?
Changes solute potential inside or outside the cell
82
Which way does water move in regards to solute potential?
Moves from areas of high to low solute concentration
83
What is the structure of a root?
```
Outer layer (epidermis)
Cortex (epidermis to endodermis)
Inner layer (endodermis)
Pericycle (tissue layer between endodermis and vascular tissue)
Stele (region containing pericycle, xylem and phloem)
```
84
What is the apoplastic pathway?
Water enters between cells
| Water moves between and through cells, but never crosses membrane (always outside cells)
85
Where is the apoplastic pathway stopped?
At the endodermis by waxy Casparian strip
86
Explain the structure of the Casparian strip
Cell walls impregnated with suberin (a waxy fat)
87
Where does the Casparian strip form a "gasket"?
Between cells of the endodermis that surround the stele
88
Is wax hydrophobic or hydrophilic?
Hydrophobic; repels water (water can only cross through cell)
89
What must occur in the Casparian strip for water and minerals to reach the pericycle?
Water and minerals from all pathways must pass through the endoderm to reach the pericycle
90
What is the role of water potential?
Cells of the pericycle pump ions into the xylem
Lowers solute potential inside the xylem
Water moves from pericycle cells into the xylem by osmosis
91
How does water move up the xylem?
Some push from below:
Water from soil entering root creates root pressure (guttation); only enough to push up to a few feet
Main source is actually pulling from above: basis of tension/cohesion model
92
What is the basis of tension in the tension/cohesion model?
Transpiration (movement of water through plants)
| Loss of water through pores in leaves called stomata; creates tension in the column of water in the xylem
93
What is the basis of cohesion in the tension/cohesion model?
Water molecules are very cohesive (H-bonding); water is pulled up from roots to leaves due to cohesion
94
Explain transport in the phloem
Sucrose actively transported into cells, need mechanism to "move sugar water", move from source (site of carbohydrate production) to sink (site of carbohydrate delivery/need)
95
Explain the pressure bulk flow model
In photosynthetic areas (source):
Sucrose actively transported into phloem cells, lowers solute potential inside the phloem. Water enters the phloem, creating higher pressure which allows translocation, distribution of carbohydrates through the phloem to other areas of the plants
96
In order to maintain homeostasis, what happens when conditions deviate too far from a set point?
Biochemical reactions are initiated to change conditions back toward the set point
97
What are effectors?
Glands or other organs that change the value of the condition in question back toward the set point value; a gland/organ can be both a comparator and effector (pancreas)
98
What is the hypothalamus?
A gland involved in the control of body temperature (and many other functions)
99
What happens involving the hypothalamus if body temperature is high?
Promotes heat loss via sweating and dilation of blood vessels in the skin
100
What happens involving the hypothalamus if body temperature is low?
Promotes heat conservation via shivering and constriction of blood vessels in the skin
101
What are the two ways to send a signal?
Autocrine and paracrine
102
How does autocrine signaling work?
Same cell sends and receives signal
103
How does paracrine signaling work?
One cell sends signals, other cell(s) receive signal
104
What are neurotransmitters?
Local signaling molecules
105
What kind of molecule are hormones and growth factors?
Distant signaling molecules
106
What are hormones?
Chemicals secreted into the blood stream for transport to distant targets; effective at low concentrations and affect growth, metabolism, development, and homeostasis
107
What are the three classes or hormones and examples?
Peptide hormones (insulin)
Amino acid derivatives (melatonin)
Steroid hormones derived from cholesterol (testosterone and estrogen)
108
What are the two classifications of hormones?
Lipophilic (nonpolar) and hydrophilic (polar)
109
Define lipophilic (nonpolar) hormones
Fat-soluble steroid hormones that bind to intracellular receptors and tend to act over a brief time period
110
Define hydrophilic (polar) hormones
Water-soluble, freely soluble in blood and bind to extracellular receptors and tend to have a much longer active period
111
What are endocrine glands?
Glands that secrete hormones and other substances into the bloodstream
112
What is the target of endocrine glands?
Cells that have receptors for the hormone
113
Explain the goal of a negative feedback loop
To maintain the set point
114
Explain how a negative feedback loop works
A hormone restores a set point which leads to a decreased production of that hormone
115
What happens when the set point is exceeded in one direction?
Produce hormone, produce response
116
What happens when a set point is exceeded in the opposite direction?
Reduce hormone production, reduce response
117
What is one example of a negative feedback loop?
Blood glucose
118
Explain the 2 hormones that control blood glucose and what they respond to
Insulin responds to an increase in blood glucose (beta cells) and glucagon responds to a decrease in blood glucose (alpha cells)
119
How does Type 1 Diabetes affect the negative feedback loop involved in blood glucose?
Disrupts this system; the immune system destroys the cells that produce insulin
120
What happens to blood glucose when you eat a candy bar?
Blood glucose rises, increases insulin production from the pancreas
Cells take up and metabolize glucose
Cells convert glucose to glycogen via glycogen synthase; stores it in liver and muscle
Overall result: Blood sugar falls and insulin production falls (negative feedback)
121
What happens to blood glucose when you skip lunch?
Blood glucose falls, stimulates glucagon production (pancreas)
Glucose released by liver cells
Glycogen is converted to glucose and released
Overall result: blood glucose rises and glucagon production falls (negative feedback)
122
Where is Ca++ stored?
Bone
123
Why is constant plasma Ca++ important?
Important regulatory molecule in cells
124
Regulation of plasma Ca++ involved which two hormones?
```
Parathyroid Hormone (PTH): works to increase Ca++
Calcitonin (CT): works to decrease Ca++ (illustrates proportional response)
```
125
What happens if Ca++ falls below a set point?
PTH is produced
126
What happens if Ca++ rises above a set point?
CT is produced
127
What is the advantage of proportional control?
Allows finer level of control, not just all the way on for PTH and CT production; level of PTH/CT production is proportional to how low or high Ca++ levels are (most hormone systems show this kind of control)
128
Explain hormones and development in humans
Up to 6 wks post-fertilization, males and females have Wolffian and Mullerian ducts; testosterone causes Wolffian ducts to form male organs and Mullerian ducts regress; exposure to estrogen causes Mullerian ducts to form femals organs and Wolffian ducts regress
129
What are endocrine disruptors (EDs)?
Environmental chemicals that interfere with normal endocrine (for instance, chemicals that mimic steroid hormones like BPA)
130
What are the two major branches of the immune system?
Innate immunity and adaptive immunity
131
What is innate immunity?
Blocks entry of foreign pathogens and substances
Attacks pathogens and substances that do get into the body
General focus; innate immune cells are preprogrammed to attack many common pathogens and substances
Activates immediately upon invasion
132
What is adaptive immunity?
Slower activation (4-7 days)
Specific response
Can adapt to attack new pathogens and substances
133
What is a component of innate immunity?
Skin (provides a nearly impenetrable barrier to pathogens)
134
What characteristics of skin allow for its resistance to pathogens?
Oil and sweat glands give skin a low pH which inhibits growth/survival of pathogens
Lysozyme on skin breaks down pathogenic proteins
Good microbes that outcompete pathogenic microbes
135
What are the three potential routes of infection?
Digestive tract, respiratory tract, urogenital tract
136
What do the digestive tract, respiratory tract, and urogenital tract have in common?
All lined by epithelial cells that secrete mucus which traps microbes
137
Explain how the digestive tract protects against microbes
Salivary lysozyme; acidic stomach
| Nonpathogenic normal flora (good microbes that block pathogens)
138
Explain how the respiratory tract protects against microbes
Cilia sweep out microbes and dirt trapped in musus
139
Explain how the urogenital tract protects against microbes
Acidic urine, normal flora (good microbes)
140
What are the leukocytes that make up the innate immune system called?
Phagocytes (cells that eat)
141
What are phagocytes capable of?
Engulfing pathogens and destroying them
142
What are the two types of phagocytes?
Macrophages and neutrophils
143
What is the role of macrophages?
Kill microorganisms through phagocytosis
144
What are neutrophils?
Most abundant circulating leukocyte, also use phagocytosis
145
How do phagocytes know what to attack?
Phagocytes are pre-programmed to recognize general patterns associated with pathogens (e.g. substances commonly present on the surface of pathogens like bacteria, viruses, and fungi). Also, they recognize proteins of the complement system. Proteins that stick to pathogens marking them for destruction by phagocytes
146
What do phagocytes use to recognize patterns associated with pathogens?
Pattern Recognition Receptors (PRRs)
147
What do cytokines do?
Alarm signals that call phagocytes to activate and recruit to wounds and sites of infection
148
What is another name for activation and recruitment of immune cells?
Inflammation
149
What release cytokines?
Injured or infected cells, and other chemicals that increase cytokine production (histamine)
150
What happens when an inflammatory response occurs?
Cytokine release causes nearby blood vessels to dilate and increase in permeability, to promote phagocyte accumulation/activation.
151
What are the hallmark signs of an inflammatory response?
Redness, warmth, swelling (edema), pain
152
What are the four characteristics of adaptive immunity?
1. Set in motion by the detection of antigens
2. A large diversity of antigens can be recognized
3. Memory: slow response to new antigens; much faster response to antigens it has seen before
4. Ability to distinguish self-antigens from non self-antigens
153
What is an antigen?
A molecule that provokes an adaptive immune response
154
What types of molecules can be antigens?
Molecules (sugars, proteins, lipids, etc) found on the surface of pathogens
155
What is an epitope?
The part of an antigen that is the focus of an adaptive immune response; one antigen can have multiple epitopes
156
What binds epitopes?
Antibodies: proteins made by the immune system that stick to the epitopes of antigens
157
What is the structure of an antibody?
Tetramer (2 light ans 2 heavy chain proteins held together by disulfide bridges)
Variable regions attach to epitopes
The Fc (constant region) is recognized by cells of the specific and innate immune system
Antibodies can circulate freely or be attached to the membrane of an immune cell
158
What roles does an antibody perform?
Does NOT kill pathogens
Binding to pathogen marks it for destruction by phagocytes
Binding to bacteria/viruses blocks entry into cells/tissues
Binding to toxins blocks them from binding to/entering cells
159
What are the two cells of the adaptive immune system?
B lymphocytes/B cells and T lymphocytes/T cells
160
What is the role of B cells/lymphocytes?
Make antibodies and respond to epitopes by secreting antibodies to those epitopes
161
What is the role of T cells/lymphocytes?
Regulate other immune cells and also kill cells infected with pathogens
162
How does B cell activation work?
When a circulating B cell finds an epitope to match its activated antibody, it becomes activated.
It begins dividing, producing and secreting its antibody into circulation, and activates T cells
163
What is the first encounter with a foreign antigen called?
Primary immune response
164
What happens during a primary immune response?
Only a few B/T cells can recognize new epitopes and mount a (slow) response
Memory B/T cells remain after the infection is over
165
What is the second encounter with a foreign antigen called?
Secondary immune response
166
What occurs during a secondary immune response?
Memory T/B cells recognize antigen quickly and in greater numbers, so response is faster and more effective
167
What are vaccines?
Contain antigens that are injected into the body or taken orally
Cause an immune response leading to production of ‘memory’ B and T cells that offer long-lasting protection against a particular pathogen
If you are then exposed to that disease your adaptive immune system will quickly kill it
168
What is acquired immunity?
short-term protection against particular pathogens by maternal antibodies (acquired across the placenta or in breastmilk)
169
What are booster vaccinations?
required for some diseases; some vaccines may not produce enough memory cells to give life-long immunity
170
Give two examples of booster vaccinations
Tetanus and diphtheria: every 10 years
| Shingles (chickenpox): adults over 60
171
What is immunological tolerance?
recognition of self-antigens (autoreactive B and T cells killed)
172
What causes autoimmune diseases?
Failure of immune tolerance (autoreactive cells survive)
173
What happens when autoreactive cells attack the body?
Inflammation and organ damage; treated with immunosuppressive medications and anti-inflammatory drugs
174
What are allergies?
greatly heightened immune response to an antigen (allergen)
175
What do allergies result from?
excessive antibody production to particular antigens (can be food, medicine, pollen, dander, etc.)
176
How do some pathogens evade the immune system?
some pathogens can alter their surface antigens to avoid immune system detection
177
What two antigenetic proteins does influenza express on the surface?
HA and NA
178
What is antigenic drift?
during viral replication, point mutations occur to the HA and NA genes that alter the epitopes (evades antibody binding)
179
What does salmonella typhimurium do?
can alternate between expression of different flagellar proteins (evaded antibody binding)
180
What does neisseria gonorrhoeae do?
secretes proteases that degrade antibodies (prevents antibody mediated immune response)
181
Since animals must eliminate metabolic waste products, what do carbohydrates and fat end up as?
Water and Co2 and are easily eliminated
182
What system processes waste?
Excretory system
183
How does the excretory system process waste?
Processes and concentrates waste and toxic substances in kidneys; maintains normal concentrations of solutes and water in the blood
184
What is the order of waste and water travel?
Blood...kidneys...ureter...bladder...excreted through urethra
185
What are the three components of kidney function?
1. Blood filtration: produces filtrate (Water and solutes) for processing
2. Reabsorption of some water and solutes from the filtrate (back into blood stream)
3. Secretion of toxic substances and some water (secreted filtrate is urine
186
What is a nephron?
Processing unit of the kidney
187
Which two arterioles feed the glomerulus?
```
Afferent arteriole (blood enters)
Efferent arteriole (blood exits)
```
188
What stays and leaves in blood of the glomerulus?
Water and small molecules (filtrate) leave blood, larger molecules and cells remain
189
What is Bowman's Capsule?
Where filtrate is collected, beginning or tubule system (filtrate processing occurs in tubule system)
190
What order is the flow of filtrate?
glomerulus…bowman’s capsule…proximal tube…loop of henle….distal tubule…collecting duct
191
What order is the flow of filtrate (urine)?
collecting duct (end of nephron)…ureter…bladder…urethra (urination)
192
What happens as the filtrate travels through nephron tubules?
Water and beneficial solutes are reabsorbed into the blood stream
193
What is reabsorbed out of tubules back to blood?
Water and important solutes
194
During reabsorption, what things are actively transported?
Glucose, amino acids, Na+, Cl-
195
During reabsorption, what is the role of peritubular capillaries?
How water and solutes are returned to the blood stream from the tubules
196
What is secretion?
water and solutes that are not reabsorbed; toxic substances and some water remain in the tubule system for excretion as urine
197
What does kidney/renal failure result in?
```
Salt and water retention (high blood pressure)
Urea retention (uremic poisoning)
Decreasing blood Ph (acidosis)
```
198
What does dialysis do?
passes blood through membrane channels bathed in a plasma-like solution to remove wastes
199
What does antidiuretic hormone (ADH) do?
Controls water permeability in the collecting duct (CD)
Acts on water channels (aquaporins) in the collecting ducts, increasing aquaporin gene expression and increasing number of water channels in the CD (more water transported back into the body from urine)
200
What happens with more ADH?
More water retention
201
What happens in ADH is absent or at low levels?
CD impermeable to water
Water remains in CD (not reabsorbed)
Results in water loss from body into urine
202
What happens with low ADH?
Less water retention
203
What happens in ADH is present at high levels?
CD permeable to water
Water reabsorbed from urine
Results in water retention
204
How does alcohol affect ADH production?
Decreases ADH production
CD impermeable
Water remains in CD (not reabsorbed)
Results in LARGE loss of water in the urine
Causes dehydration and contributes to hangovers
