RAT 20 Flashcards
(132 cards)
1
Q
what is spermatogenesis?
A
the process of male gamete, sperm cells, development
2
Q
what are sustentacular cells?
A
supporting cells that surround spermatogenic cells
3
Q
what are some other names of sustentacular cells?
A
nurse cells
4
Q
what forms the blood-testis barrier?
A
tight junctions created by sustentacular cells that are bound together
5
Q
why is the blood-testis barrier so important?
A
immune cells in the bloodstream must be prevented from encountering the new antigens on the gentically unique sperm cells, as they could recognize them as foreign and mount an immune response against them
6
Q
what are some functions of sustentacular cells?
A
- providing structural support for spermatogonia developement
- secreting substances that stimulate mitosis of spermatogonia and initiation of meiosis in response to testosterone and follicle-stimulating hormone
- providing nutrients to the dividing cells
- phagocytizing damaged spermatogenic cells
- producing ABP
7
Q
what are the regions of a mature sperm?
A
- head
- midpiece
- tail
8
Q
what is the first-teir control in the hypothalamic-pituitary-gondal (HPG) axis?
A
the hypothalamus secretes GnRH
9
Q
what is the second-teir control in the HPG axis?
A
GnRH stimulates the anterior pituitary to secrete gonadotropins: FSH and LH also called interstitial cell-stimulating hormone (ICSH) in males
10
Q
what is the third-tier control in the HPG axis? what is the effect of the hormones produced?
A
- the testes are the target organs of FSH and LH
- LH stimulates the interstitial cells to produce testosterone
- FSH stimulates the sustentacular cells to secrete ABP and inhibin
11
Q
what is sexual intercourse?
A
the insertion of the male penis into the copulatory organ of the female, the vagina
12
Q
what are some other terms for sexual intercourse?
A
copulation or coitus
13
Q
what are the basic phases of the male sexual response?
A
- erection: enlargement and stiffening of the penis
- ejaculation: process by which semen is expelled from the penis
14
Q
describe the changes that occur leading to an erection.
A
- blood vessel in the penis that supply erectile issue are consisted
- the penis is in flaccid (relaxed) state
15
Q
what stimuli can lead to an erection?
A
sexual stimuli (touch, mechanical stimulation, erotic sounds)
16
Q
what is ejaculation?
A
process by which semen is expelled from the penis
17
Q
what are the two phases of ejaculation?
A
- emission
- expulsion
18
Q
what occurs during emission?
A
the movement of sperm and testicular fluid, as well as, secretions from the prostate gland and seminal vesicle into the urethra
19
Q
what occurs during expulsion?
A
explusion of semen through the urethra
20
Q
what is orgasm?
A
- the time period during which feeling of pleasure are experienced
- in males, this coincides with ejaculation
21
Q
what is resolution?
A
- relaxation: blood vessels and blood sinuses constrcit forcing blood out of the penis, becomes flaccid again
22
Q
what is the refractory period?
A
the latent period: a man is unable to achieve another orgasm (minutes to hours)
23
Q
what hormonal changes occur during puberty?
A
- level of hormone produced increases greatly
- responsible for growth, maturation, and maintenance of male reproductive organs
24
Q
list some male secondary sexual characteristics.
A
- growth of pubic, axillary, and facial hair
- enhanced hair growth on the chest
- enlarged pharynx, thicker vocal cords
- thickened skin and increased secretions of sebacous glands
25
how does testosterone affect bones?
makes bone denser; more calcium is deposited
26
how does testosterone affect skeletal muscle?
skeletal muscle mass increases
27
how does testosterone affect erythropoiesis?
increases; males have more erythrocytes than females
28
how does testosterone affect libido?
increases
29
what is male climacteric?
- andropause
- the period in which reproductive function sbegin to decline in men
30
what hormonal changes occur during male climateric?
- size and wieght of testes might decrease
- number of sustentacular and interstitial cells begins to decline
- high levels of LH and FSH
- lowers levels of testosterone
- fewer sperm produced
- depressed mood, fatigue
31
name some similarities between the male and female reproductive system
- both systems produce sex hormones and gametes
- both have a series of ducts to move the gametes
32
what primary additional function does the female reproductive system have?
support a developing conceptus and nourish an infant
33
describe the size of the ovaries
walnut; weight 6-8 grams
34
describe the location of the ovaries
lateral walls of the pelvic cavity
35
why do the ovaries appear bumpy?
bumpy due to scars left behind when ova are released approximately once per month
36
what are the primary functions of the ovaries?
- produce ova
- secrete several hormones (estrogen and progesterone)
37
what are the regions of the ovaries?
- ovarian cortex
- ovarian medulla
38
what is found in the ovarian cortex?
site of oogenesis; follicles
39
what is found in the ovarian medulla?
blood vessels, lymphatic vessels, and nerves
40
what are the three ligaments that hold the ovaries in place?
- broad ligament
- ovarian ligament
- suspensory ligament
41
describe the broad ligament
a large, flat ligamnet that attaches to the ovaries, uterin etubes, and uterus, and connects them to the pelvis
42
describe the ovarian ligament
connects the medial surface of the ovary to the uterus
43
describe the suspensory ligament
connect sthe lateral surface of the ovary to the pelvic wall; carries the ovarian artery and ovarian vein
44
describe the size and location of the uterine tubes
- approximately 10 cm long
- extends medially from the ovary to the superior and lateral refion of the uterus
45
what are some alternate names for the uterine tubes?
- fallopian tubes
- oviducts
46
what are the regions of the uterine tube?
- isthmus
- ampulla
- infundibulum
47
describe the fimbriae
finger-like projections that drape over the ovary and "catch" an oocyte that is released for an ovary during ovulation
48
what happens during ovulation?
the ovary expels a secondary occyte
49
what is the function of the oviduct?
collect the ovulated ovum in the infundibulum which guides the egg into the oviduct
50
what is the usual site of fertilization?
uterus
51
what are the functions of the uterus?
provides protection and nutritional support for a devleoping conceptus
52
what is the common term for uterus?
womb
53
describe the size and shape of the uterus.
- inverted pear
- weighs 30-40 grams
54
what are the three layers of the uterine wall?
- perimetrium
- myometrium
- endometrium
55
what are the functions of the vagina?
- female organ of capulation
- passageway for delivery of a fetus and for menstral flow
56
describe the size of the vagina
thinck walled tube 8-10 cm
57
describe the location of the vagina
- extends from the cervix to the exterior of the body
- parallels the anterior urethra
58
what is the term for the ridges in the wall of the vagina?
rugae
59
why is the pH kept low in the vagina?
keeps the vagina helathy and free of infection
60
what epithelium lines the adult vagina?
stratified squamous epithelium
61
what is the hymen?
an incomplete partition formed by the mucosa near the distal vaginal orifice
62
what is the collective term for the external female gentialia?
vulva
63
what is a mammary gland?
a part of the integumentary system; actually a modified sweat gland
64
what is an areola?
pigmented skin that surrounds the nipple
65
what is a nipple?
central protruding through which milk exits
66
what is the percetnage of water in a "stardard man"?
60%
67
why would this vaue vary from person to person?
most people do not fit the profile of the standard man
68
describe the two basic compartments where fluid is found.
- intracellular compartment: inside the cell
- extracellular compartment: outside the cell
69
what percetnage of total body fluid is found inside of cells?
60%
70
name two extravellular fluids
- plasma
- interstitial fluids
71
what is the main difference between the compositions of plasma and interstitial fluid?
protein content (higher in plasma)
72
is sodium ion concentration higher in the ECF or the ICF?
ECF
73
is chloride ion concentration higher in the ECF or the ICF?
ECF
74
is calcium ion concentration higher in the ECF or the ICF?
ECF
75
is protein concentration higher in the ECF or the ICF?
ICF
76
is potassium ion concentration higher in the ECF or the ICF?
ICF
77
what is the most abundant intracellular cation?
potassium
78
what is the most abundant extracellular cation?
sodium
79
can water move freely between compartments?
yes
80
what two forces determine the direction of the movement of water?
- hydrostatic pressure gradient
- osmotic pressure gradient
81
what direction does water move based on hydrostatic gradients?
area of higher hydrostatic pressure to one with lower hydrostatic pressure
82
what direction does water move based on osmotic pressure?
toward the solution with the higher osmotic pressure
83
what determines the osmotic pressure of a solution?
the number of solute particles present in the solution (osmolarity)
84
explain the effect of hydrostatic pressure with respect to water movement
water is forced out of the capillary
85
what happens if the hydrostatic pressure of plasma increases?
drives water into the cell
86
what happens if the hydrostatic pressure of plasma decreases?
less water moves out of the capillary and into the interstitial fluid
87
why is there normally no net osmotic movement between the ECF and the cytosol?
they are isotonic and have the same osmotic pressure
88
what can change this?
when the ECF's concentration is altered causing the osmotic pressure to change
89
what happens at the arterial end of a capillary?
- the plasma has a high hydrostatic pressure much higher than the interstitial fluid
- water is lost
90
what happens at the venous end of a capillary?
water drawn back into the capillary
91
under normal conditions, how do the hydrostatic and osmotic pressures of the inerstitial fluid and cytosol compare?
they are very close so there is no significant gradient so no net water movement
92
when you drink water, what happens to the plasma volume?
increases
93
when you drink water, what happens to the hydrostatic pressure?
increases
94
when you drink water, what happens to the osmotic pressure?
decreases
95
would these changes favor capillary filtration or capillary reabsorption?
capillary reabsorption
96
what happens to cells in a hypotonic fluid
cell swells
97
when there are water lossess, what happens to the plasma volume?
decreases
98
when there are water lossess, what happens to the blood hydrostatic pressure?
decreases
99
when there are water lossess, what happens to the blood osmotic pressure?
increases
100
would these changes favor capillary filtration or capillary reabsorption?
capillary filtration
101
what happens to cells in a hypertinic fluid?
cell shrinks
102
what is obligatory water loss?
a certain amount of urine that must be produced each day irrespective of fluid intake
103
what volume is a typical daily obligatory water loss?
500 mL
104
what is sensible water loss?
water loss that is "sensed" or noticed; includes urine and feces
105
what is insensible water loss?
water loss that is unnoticed; includes sweat and ventilation
106
what is metbaolic water?
water produced as a byproduct of metabolic reactions
107
what part of the body controls the thirst mechanism?
hypothalamus
108
hat is the most potent trigger for thirst?
increase in osmolarity of the plasma
109
why does our thirst go away before the plasma osmolariyt is restored?
due to receptors in the pharynx that detect the ingestion of liquid
110
what are other stimuli that can trigger thirst?
- decreased plasma volume
- angiotensin- II
111
how much water do we need to drink?
2-5 liters per day
112
does drinking excess water help people loss weight?
no
113
list four hormones that regulate water balance. which hormone is most improtant?
- ADH: most important
- angiotensin-II
- aldosterone
- ANP
114
what are some primary mechanisms to prevent imbalances of fluid homeostasis?
altering urine output
115
define dehydration
decreased volume and increaseed concentration of the ECF
116
what are some common causes of dehyration?
- profuse sweating
- prolonged diarrhea and/or vomitting
- certain endocrine conditions
- overuse of dieuretics
117
what happens to cells during dehydration?
cells shrink
118
what are the signs and sympotoms of dehydration?
- dry mouth and thirst
- dryness of skin
- decreased urine production
- fever
- organ function imparied
119
why is consuming pure water potentially problematic for someone who is dehydrated? how can this potentially be prevented?
- the ECF can become overly dilute, causing too much water to enter the cells and resulting in cellular swelling
- sports drinks
120
define overhydration
the volume of the ECF increases and its osmotic pressure falls
121
what happens to cells during overhydration?
cells swell
122
how is overhydration normally prevented?
a decline in ADH production which leads to loss of excess water in the urine
123
what is water toxicity?
extreme amounts of water are consumed in short period of time
124
what is hyponatremia?
when the sodium ion concentration falls dramatically
125
what are the signs and symptoms of hypoatremia?
- mental status changes
- seizures
- coma
- even death
126
how can overhydration/hypoatermia be treated?
administering hypertonic fluids to draw the water back out of the cells and into the interstitial fluid
127
what is an isosmotic fluid imbalance?
disruption in homeostasis when the ECF remains isotonic to the cytosol
128
what is hypovolemia?
plasma osmotic pressure is unchanged and there is no osmotic gradient to pull water into or out of the cell
129
what can cause hypovolemia?
fluid depletion in cases of blood loss
130
at are some signs and symptoms of hypovolemia?
shock, organ failure, death to extremely low blood pressure
131
what is hypervolemia? what is a common example?
- the ECF can increase without a signficant change in osmotic pressure; fluid excess
- edema
132
what can cause edema?
- high hydrostatic pressure
- hypertension
- decrease in return of venous blood to the heart
- excess sodium ion retention
- low colloid osmotic pressure
- removal of lymphatic vessels
- release of inflammatory mediators
