Homeostasis Flashcards
(130 cards)
1
Q
What is homeostasis?
A
Homeostasis is the body’s internal system adjusting to changing conditions in the internal/external environment
2
Q
All homeostatic systems have three components. What are they?
A
- Sensor (senses stimulus)
- Control centre/integrator (usually the brain)
- Regulator/ effector that carries out the response
3
Q
What kind of receptors in the skin detect a decrease in temperature?
A
Thermoreceptors
4
Q
Breakdown of thermoreceptors:
- Send message to integrator, ___________ to secrete ________.
- Blood carries _____ to the _____ gland.
- _____ signals the pituitary gland to secrete _______ into blood.
- Blood carries _____ to the thyroid.
- Thyroid produces and secretes ______.
A
Breakdown of thermoreceptors:
- Send message to integrator, hypothalamus to secrete TRH (thyroid releasing hormone).
- Blood carries TRH to the pituitary gland.
- TRH signals the pituitary gland to secrete TSH (thyroid stimulating hormone) into blood.
- Blood carries TSH to the thyroid.
- Thyroid produces and secretes thyroxine.
5
Q
Thyroxine tells all body cells to increase _______ metabolism, increasing ________ in the body.
A
glucose metabolism, heat production (temperature)
6
Q
What is a dynamic equilibrium?
A
A condition that remains stable with fluctuating limits
7
Q
In regards to TRH and TSH, which part of the pituitary are they involved in?
(anterior or posterior)
A
Anteriori pituitary
8
Q
When the body becomes too _____, ________ feedback tells the hypothalamus to slow the production of _____.
A
hot (too much thyroxine), hypo slows production of TRH
9
Q
There are two types of thyroxine, T3 and T4. What is the diff between the two?
A
T4: four iodine atoms and T3: three iodine atoms
10
Q
What is the main characteristic of hyperthyroidism?
A
Too much thyroxine in the blood.
11
Q
In hyperthyroidism, ________ is too high. This may cause which 3 symptoms?
A
Metabolism is too high.
Symptoms:
1. loss of weight
2. excessive sweating
3. bulging eyes (Grave’s disease)
4. goiter (swelling of the thyroid)
12
Q
What is an autoimmune disease? What are autoimmune diseases related to hypo/hyper?
A
Condition in which the body’s immune system mistakes its own healthy tissues as foreign and attacks them
Hyper: Graves
Hypo: Hashimotos
13
Q
What are three causes of Hyperthyroidism ?
A
- Cancer
- Thyroiditis (infection of thyroid)
- Thyroid Stimulating Antibody that kills healthy tissue (Grave’s disease)
14
Q
Why is radioactive iodine used to treat hyperthyroidism?
A
Radioactive iodine kills thyroid cells such that less thyroxine is produced
15
Q
What Hypothyroidism? What are 3 symptoms?
A
A condition in which the thyroid does not produce enough thyroxine (levels in blood are too low)
- Weight gain
- Feeling cold
- Goiter
16
Q
What are 3 causes of hypothyroidism and a treatment option?
A
Causes:
1. Treatment of hyper can cause hypo
2. Hashimoto’s
3. Pituitary disorder (not enough TSH)
Treatment: thyroxine supplements
17
Q
In both hypo and hyper thyroidism, a goiter forms. Why?
Hyper: thyroid produces excess ______
Hypo: ______ levels are too high due to low levels of thyroxine. No _______ feedback to ________.
A
Hyper: thyroid produces excess thyroxine
Hypo: TSH levels are too high due to low levels of thyroxine. No negative feedback to hypothalamus.
18
Q
Thermoregulation is how the body controls _______.
A
Temperature
19
Q
What is the difference between how endotherms and ectotherms regulate temperature?
A
Endotherms: maintain body temp w internal mechanisms (ex. shivering, dilation of vessels in humans)
Ectotherms: absorb therm energy from environment (fish, reptiles)
20
Q
Which region of the brain controls temp?
A
Hypothalamus
21
Q
What is the difference between peripheral and central nerve receptors?
A
Central receptors: arteries/organs monitor core temp (slightly higher)
Peripheral receptors: in skin monitor skin temp
22
Q
What is the difference between skeletal and smooth muscle?
A
Skeletal: can contract
Smooth: non-contractable (rib/diaphragm)
23
Q
What is the difference between positive and negative feedback loops?
A
Negative loop: wants to offset the stimulus
Positive loop: wants to increase the effect of the stimulus
24
Q
How do negative feedback loops control temp? (3 steps)
A
- Cold temp stimulates the thermoreceptors in skin
- Send message to hypothalamus to integrate
- Hypothalamus tells the sweat glands to sweat
25
How does a negative feedback loop return stop? Why can't one sweat forever?
Eventually sweat produced causes the body to become too cold. It dips below the set point. This serves as a new stimulus
26
Positive feedback loops move a _________ variable away from a ______ state. This causes the process to move _____ {speed} and it STOPS
controlled variable away from a steady state. It is quick
27
Growing a baby, there are high levels of the hormone \_\_\_\_\_\_\_\_. Upon a decrease, _________ start in the womb.
progesterone, contractions
28
Small contractions move baby towards opening of the uterus, \_\_\_\_\_\_. This causes _______ to be released, which targets the ______ and causes stronger contractions.
cervix, oxytocin, uterus
29
When temp falls below the set point in a home, thermostat (\_\_\_\_\_\_\_) switches on furnace (\_\_\_\_\_\_\_\_). When temp is above set point, thermostat turns off furnace.
sensor, effector (regulator)
30
What is osmotic pressure? (pressure results from...)
Pressure that results from a difference in solutes between 2 sides of a permeable membrane
31
Which process regulates osmotic pressure of bodily fluids and cells?
Osmoregulation
32
Hyposmotic solutions have a _______ concentration of water. Hyperosmotic solutions have a _____ concentration of water (more solute).
hyposmotic: higher { } of water
hyperosmotic: lower { } of water
33
Deamination is the process by which an _______ group is ______ from an amino acid. The amino group is converted to \_\_\_\_\_\_\_. The rest of the amino acid is oxidized to produce \_\_\_\_\_\_\_.
Deamination is the process by which an amino group is removed from an amino acid. The amino group is converted to ammonia. The rest of the amino acid is oxidized to produce energy.
34
Ammonia is ______ (toxic/non-toxic). It combines in urea to form a less toxic form. It is secreted by which creatures?
Ammonia is toxic.
Animals that produce urea include mammals, sharks, adult amphibians, etc.
35
How do mineral salts play a role in osmoregulation?
Salt and sugar creates a concentration gradient that causes pressure. This pressure moves water outside and inside of cells to that they are isotonic
36
What are three functions of the kidney?
1. Remove excess urea from the blood
2. Maintain water balance in the blood
3. Maintain pH balance in the blood
37
The renal artery carries fresh blood from the ______ to the kidney.
aorta
38
The renal vein carries filtered blood from the kidneys to the _______ \_\_\_\_ \_\_\_\_\_.
inferior vena cava
39
the renal pelvis connects the kidney to the ________ through which urine goes to the \_\_\_\_\_\_\_.
ureter, bladder
40
What is the inner layer of the kidney called? the outer layer?
inner: renal medulla
outer: renal cortex
41
The afferent arteriole supplies blood to kidney, directly to the \_\_\_\_\_\_\_\_\_\_
glomerulus
42
The efferent arteriole carries _______ blood away from the _________ to the _________ capillaries and eventually _______ vena cava.
The efferent arteriole carries filtered blood away from the glomerulus to the peri tubular capillaries and eventually inferior vena cava.
43
The proximal tubule connects the _________ \_\_\_\_\_\_ to the loop of Henle.
The distal tubule connects the loop of Henle to the __________ duct.
prox: Bowman's capsule
distal: collecting
44
What is the glomerulus?
Network of capillaries that perform the first step in the filtration of blood
45
What are the three steps in urine production?
Filtration, re-absorption, secretion
46
In filtration, only small things from the ________ (blood) are filtered to the ________ \_\_\_\_\_\_\_ (tubule)
glomerulus (blood), bowman's capsule (tubule)
47
In filtration, only small things from the ________ (blood) are filtered to the ________ \_\_\_\_\_\_\_ (tubule). What do these include?
glomerulus (blood), bowman's capsule (tubule)
1. amino acids
2. water
3. NaCl
4. glucose
5. Urea
48
What are 3 things not filtered during filtration?
1. Proteins
2. Blood cells
3. Some water and salts
49
There are two types of re-absorption. One occurs in the _______ tubule, the other in the loop of \_\_\_\_\_\_.
proximal tubule and loop of Henle
50
How much filtrate is excreted as urine?
1.5 L
51
Re-absorption in the loop of Henle is when ______ re-enters the blood via \_\_\_\_\_\_\_. As _______ leaves the tubule, the filtrate becomes more concentrated.
Re-absorption is when water re-enters the blood via osmosis. As water leaves the tubule, the filtrate becomes more concentrated.
52
What leaves the tubule in the descending loop of Henle? What is not permeable?
Water leaves. Ions are not permeable
53
What leaves the tubule in the ascending loop of Henle? What is not permeable?
Ions (Na+, Cl-). Water is not permeable
54
Since we are creating a _____ gradient, the ________ is said to be salty.
salt, medulla
55
\_\_\_\_\_\_\_\_\_ reabsorption occurs in the proximal tubule. The nephron _______ transports \_\_\_\_\_\_, amino acids and _____ ions back into the blood to be used. Cl- ions follow and enter \_\_\_\_\_\_.
Selective reabsorption occurs in the proximal tubule. The nephron actively transports glucose, amino acids and Na+ ions back into the blood to be used. Cl- ions follow and enter passively.
56
Secretion is the movement of waste in the ______ back into the tubule via ______ transport. What are some examples?
Secretion is the movement of waste in the blood back into the tubule via active transport. Ex. urea, vitamin C, drugs, H+
57
During secretion, urine is collected into the ________ duct and via the renal _______ passes into the \_\_\_\_\_\_\_.
collecting duct, pelvis, bladder
58
Why can blood cells and proteins not be filtered?
Too big to pass capillary wall
59
where is the highest concentration of Na+ found?
bottom of the loop of Henle
60
The kidney has the ability to restore the pH only if it is too \_\_\_\_? (high/low). This means there are too many ____ ions.
Low, H+
61
the nephron will do two things to lower pH
1. reabsorb _____ (binds to H+) and lowers H+ in blood
2. secrete H+ (blood to tubule to be excreted as \_\_\_\_\_\_)
HCO3-, urine
62
When the _________ detects increased solute in the blood, it gives posterior pituitary a signal to release ____ into the \_\_\_\_\_\_\_\_.
When the hypothalamus detects increased solute in the blood, it gives posterior pituitary a signal to release ADH into the blood.
63
What does ADH stand for? What does it do?
Ant-diruetic hormone. Causes kidneys to release water (reabsorb water)
64
ADH targets the ________ duct of a nephron by decreasing _____ excretion. (note: water is not in nephron, it is in the blood)
collecting duct, urine
65
Eventually, when there is too much water in the blood there it too low \_\_\_\_\_. __________ detects this and tells posterior pituitary to stop releasing \_\_\_\_\_\_.
solute, hypothalamus, ADH
66
If alcoholic drinks inhibit ADH, what is there main symptom?
pee more, thus more dehydrated
67
Which kind of diabetes produces not enough ADH? What is the main symptom?
Peeing a lot, feeling thirsty
68
The stimulus for the kidney and blood pressure relationship is ______ blood pressure due to ______ blood volume.
low, low
69
What specialized group of cells first detects low blood pressure? Which arteriole are they found in?
JGA (juxtaglomerular apparatus), found in afferent arteriole
70
JGA converts in inactive protein angiotensinogen into \_\_\_\_\_\_\_\_.
This targets the adrenal gland, which produces the hormone \_\_\_\_\_\_\_\_.
This hormone causes more _____ to be reabsorbed into the blood. Since water follows \_\_\_\_\_\_\_, water volume increases.
More water = more \_\_\_\_\_\_\_.
JGA converts in inactive protein angiotensinogen into angiotensin.
This targets the adrenal gland, which produces the hormone aldosterone.
This hormone causes more Na+ to be reabsorbed into the blood. Since water follows solute, water volume increases.
More water = more pressure.
71
What are hormones?
Chemical secreted into blood by cells of the endocrine system
72
Endocrine glands are ______ the body. What are 3 examples?
inside
examples: adrenal, pituitary, thyroid
73
What are the two main differences between protein hormones and steroid hormones? (note: solubility and ability to pass membrane)
1. protein hormones: water soluble, bind to cell membrane receptors
2. steroid hormones: non-water soluble, pass through the plasma membrane and attach to receptors inside the cell
74
The hypothalamus produces __________ cells in both the posterior and anterior pituitary glands. But in which side do the cells contain a releasing hormone?
neurosecretory, anterior pituitary neurosecretory cells have releasing hormones
75
Hormones are produced by the ________ and carried directly to the _________ pituitary and released into the blood.
hypothalamus, posterior
76
neurosecretory release ________ hormones into the blood. The blood carries them to the ______ lobe of the pituitary to secrete its hormones.
releasing, anterior lobe
77
which two hormones are stored in the posterior pituitary?
oxytocin and ADH
78
In the long-term stress response, the hypothalamus secretes a ________ hormone (ACRH).
BONUS: what does it stand for?
releasing
Adrenocorticotropin Releasing Hormone
79
ACRH causes which lobe of the pituitary to release ACTH?
BONUS: what does ACTH stand for?
The anterior lobe.
ACTH stands for anteriorcorticotropin hormone
80
ACTH is carried by blood to the ______ cortex where is secretes which two corticoids?
adrenal cortex
1. glucocorticoids
2. mineralocorticoids
81
Mineralocortocids increase the amount of _____ ions in the kidney. This causes _____ to follow and therefore increased ______ pressure.
Na+, water, blood pressure
82
Glucocorticoids cause proteins and fats to be ______ down and converted into \_\_\_\_\_\_. This _______ system is also suppressed, making one more likely to develop a \_\_\_\_\_.
Glucocorticoids cause proteins and fats to be broken down and converted into glucose. This immune system is also suppressed, making one more likely to develop a cold.
83
During the short-term stress response, cells in the hypothalamus send signals to _______ cells in the ______ cord.
Cells in the ______ cord stimulate adrenal _______ to secrete \_\_\_\_\_\_\_\_\_.
During the short-term stress response, cells in the hypothalamus send signals to nerve cells in the spinal cord.
Cells in the spinal cord stimulate adrenal medulla to secrete epinephrine.
84
Epinephrine causes increased \_\_\_\_\_\_\_. Glycogen to be converted into ______ for the body to use. There are also changes in ______ flow pattern to increase circulation.
Epinephrine causes increased metabolism. Glycogen to be converted into glucose for the body to use. There are also changes in blood flow pattern to increase circulation.
85
Most of the pancreas is an _______ gland. 2% of the cells in the pancreas are specialized _______ cells that form clusters called the _____ of \_\_\_\_\_\_\_\_.
Most of the pancreas is an exocrine gland. 2% of the cells in the pancreas are specialized cells that form clusters called the islets of Langerhans.
86
The islets of langerhan contain alpha and beta cells. Alpha cells produce _______ and beta cells produce \_\_\_\_\_\_.
alpha: glucagon
beta: insulin
87
What event would cause beta cells to produce insulin?
A rise in blood glucose after a meal
88
Insulin instructs the body to _____ its blood glucose levels.
It targets _____ body cells and tells them to take up glucose.
lower, all
89
What does insulin inhibit in the liver?
The breakdown of glycogen into glucose
90
Insulin promotes _____ tissue to uptake glucose while ________ the breakdown of fats into _____ acids.
Insulin promotes fat tissue to uptake glucose while preventing the breakdown of fats into fatty acids.
91
Glucagon produced by _____ cells have an _________ effect from insulin. This means opposite.
alpha, antagonistic
92
Glucagon _______ blood sugar levels by stimulating the breakdown of _______ into glucose.
raises, glycogen
93
Glucagon also stimulates the breakdown of fats into _____ \_\_\_\_\_\_ and proteins into _____ \_\_\_\_\_\_\_.
fatty acids, amino acids
94
A cells ability to use amino acids and non\_\_\_\_\_\_\_ helps maintain blood glucose while \_\_\_\_\_\_\_\_.
carbohydrates, fasting
95
When blood glucose is too high, beta cells turn up _______ production, and alpha cells inhibit _______ production
insulin, glucagon
96
When blood glucose levels are low, alpha cells turn up _______ production, and beta cells inhibit _______ production.
glucagon, insulin
97
Diabetes insipidous is a condition in which not enough _____ is produced. What is the body not able to do?
The body is not able to reabsorb enough water into the blood. This results in a constant need to pee
98
Diabetes mellitus is characterized by a ______ blood glucose level. What are the 3 classic symptoms?
high
1. frequent urination
2. increased thirst
3. increased apetite
99
If untreated, what are 3 long-term effects of diabetes?
1. loss of vision
2. kidney failure
3. cardiovascular problems
100
What is the difference in issues between Type 1 and Type 2 diabetes? Difference in treatment?
1: beta cells do not produce insulin, daily insulin shots
2. insulin receptors do not function properly, balanced diet
101
What is the difference onset between Type 1 and Type 2 diabetes?
type 1: usually infancy
2: adulthood
102
Type 2 is strongly associated with \_\_\_\_\_\_\_\_. There has also been found to be an 80% ______ linkage.
obesity, genetic
103
Gestational diabetes is a high blood ______ level in ________ woman.
glucose, pregnant
104
If calcium levels in the blood rise past their set point, the thyroid releases the hormone \_\_\_\_\_\_\_\_.
calcitonin
105
Calcitonin targets the ______ which will take up _______ and other mineral deposits. Calcitonin also targets the _______ which reduce calcium reabsorption into the blood (more in \_\_\_\_\_\_).
Calcitonin targets the bones which will take up calcium and other mineral deposits. Calcitonin also targets the nephrons which reduce calcium reabsorption into the blood (more in urine).
106
When blood calcium decreases below the setpoint, the _________ gland releases \_\_\_\_\_.
parathyroid, PTH
107
Mammals have ____ parathyroid glands, each about the size of a \_\_\_\_
4, a pea
108
PTH targets which three areas of the body?
1. Bones: increased calcium
2. Kidneys: increased calcium
3. Small intestine: more calcium in blood than in feces
109
calcium is essential for which two things? what can a deficiency cause? overproduction?
1. blood clotting, muscle contractions
2. not enough: twitching muscles and cramps
3. too much: weak muscles, osteoporosis
110
What are the two main phases of the menstrual/ovarian cycle?
follicular phase and luteal phase
111
During the follicular phase…
1. The hypothalamus releases \_\_\_\_\_\_\_.
2. This goes to the anterior pituitary which releases _____ and \_\_\_\_\_. These two hormones target the \_\_\_\_\_\_.
3. FSH causes several oocytes to start developing into ______ cells.
4. Only ___ develops to maturity.
1. The hypothalamus releases GnRH.
2. This goes to the anterior pituitary which releases LH and FSH. These two hormones target the ovary.
3. FSH causes several oocytes to start developing into follicle cells.
4. Only 1 develops to maturity.
112
The growing ______ under the influence of FSH and LH produce \_\_\_\_\_\_\_.
follicle, estrogen
113
At low {estrogen}, there is negative feedback on \_\_\_\_\_.
At high {estrogen}, there is positive feedback on _____ (day \_\_\_) to the hypothalamus to release more \_\_\_\_\_\_.
At low {estrogen}, there is negative feedback on FSH.
At high {estrogen}, there is positive feedback on LH (day 12) to the hypothalamus to release more GnRH.
114
When a follicle ruptures, an ____ is released and lots of _____ is secreted. This process is called \_\_\_\_\_\_.
When a follicle ruptures, an egg is released and lots of LH is secreted. This process is called ovulation.
115
LH causes a ruptured follicle to create the ________ \_\_\_\_\_\_\_.
corpus luteum
116
The buildup of the corpus luteum produces which 3 hormones in excess?
Which two hormones are inhibited?
progesterone, estrogen, inhibin
117
what does the corpus luteum do?
the corpus luteum prepares the uterus to receive a fertilized egg
118
increased levels of progesterone cause _______ feedback to the hypothalamus. this shuts down GnRH and therefore which other two hormones?
negative feedback, FSH and LH
119
Which hormone mainly promotes the thickening of the uterine lining?
progesterone
120
Inhibin specifically inhibits the release of _____ from the pituitary. This prevents the start of _____ development at around day \_\_\_\_.
Inhibin specifically inhibits the release of FSH from the pituitary. This prevents the start of follicle development at around day 14.
121
If fertilization does not occur, the ______ \_\_\_\_\_\_\_ degenerates and levels of \_\_\_\_\_\_\_\_\_, \_\_\_\_\_\_\_\_, and _______ decrease. Which two hormones are no longer inhibited?
If fertilization does not occur, the corpus luteum degenerates and levels of estrogen, progesterone, and inhibin decrease. FSH and LH are no longer inhibited.
122
why does one bleed on their period?
uterine lining is shed (endometrium)
123
if fertilization of an egg does occur, where is it implanted? Which hormone known as the pregnancy hormone, is released?
implanted in the uterine lining. HCG is known as the pregnancy hormone (Human Chronic Gonadotropin)
124
what is the main function of HCG?
prevent the degeneration of the corpus luteum
125
after 10, weeks, what takes over the function of the corpus luteum?
the placenta
126
LH targets _______ cells and tells them to release the hormone \_\_\_\_\_\_\_\_\_.
Leydig, Testosterone
127
FSH targets _______ cells. It helps a binding protein bind w _________ to stimulate ______ production.
FSH targets sertolli cells. It helps a binding protein bind w testosterone to stimulate sperm production.
128
Where do sperm develop and mature?
seminiferous tubules
129
the negative feedback system is males….
When __________ is overabundant, it tells the hypothalamus to stop producing GnRH. _______ cells are also stimulated and told to secrete inhibin needed to stop _____ production.
When testosterone is overabundant, it tells the hypothalamus to stop producing GnRH. Sertolli cells are also stimulated and told to secrete inhibin needed to stop FSH production.
130
Where are mature sperm stored?
epididymus
