Unit 4 Flashcards
what are the 2 systems that coordinate communication throughout the body?
- endocrine
- nervous
why do hormones that go through the bloodstream not affect every cell it passes
because only target cells have the receptors for the hormone
can multiple hormones act at the same target at the same time?
yes
what kind of signaling is described by target cells being close in proximity to the secreting cells?
paracrine signaling (in the same tissue)
what kind of signaling is described as the target cell is also the secreting cell?
autocrine
what kind of signaling releases a hormone into the bloodstream instead of into a synapse?
neuroendocrine signaling
what is the difference between synaptic and neuroendocrine signaling?
neuroendocrine: releases into bloodstream
synaptic: releases into synapse
which kind of gland lacks ducts and releases hormones into the blood
a. endocrine
b. exocrine
a. endocrine
which kind of gland has ducts to carry secretions to the membranes surface
a. endocrine
b. exocrine
b. exocrine
what kind of gland actually produces the hormones
a. endocrine
b. exocrine
a. endocrine
what is the hormonal stimuli of hormone release
hormone release is caused by another hromone
what is the neural stimuli of hormone release
hormone release caused by neural input
what is the humoral stimuli of hormone release
hormone release caused by altered levels if certain ions or nutrients (in the blood)
what are the 3 main classes of hormones
- amine
- peptide (protein)
- steroid
which class of hormones are synthesized from modified (smaller) amino acids
amine
which class of hormones are synthesized from amino acid chains
peptide (protein)
_ most hormones
which class of hormones are synthesized from cholesterol on demand
steroid
why do steroid hormones have to be synthesized on demand (when it is needed)
because they cannot be stored (not soluble in water)
which hormone classes can be stored
amine and peptide
what are some effects hormone action does on target cells
- alter plasma membrane permeability
- stimulate synthesis of other hormones/ proteins
- activate/ deactivate enzymes
- stimulate mitosis
- induce secretory activity
in which 2 ways do hormones act on receptors based on chemical nature/ receptor location
- water soluble hormones
- lipid-soluble hormones
which kinds of hormones are water soluble
all amine based hormones EXCEPT thyroid hormone
what does it mean to be a water-soluble hormone
- travel freely in the bloodstream
- cannot enter the cell
- binds to the OUTSIDE of cell (plasma membrane receptors)
what does it mean to be a lipid-soluble hormone
- travel through the bloodstream bound to a transport protein
- can enter the cell
- binds to intracellular receptors
why are protein based hormones not able to enter the cell
bc they are H2O soluble
which signaling mechanism is known for water soluble hormones to start when binds to the plasma membrane
cAMP signaling pathway
what are the 5 steps of the cAMP pathway
- hormone binds to the plasma membrane receptor
- receptor activates G protein (has a GTP)
- G protein activates adenylate cyclase
- adenylate cyclase converts ATP to cAMP
- cAMP activates protein kinases
what is the secondary messenger in the cAMP pathway
cAMP
where do lipid soluble hormones bind to their receptors
in the cytoplasm or nucleus
what kinds of hormones are lipid-soluble
steroid and thyroid
the response to a lipid soluble hormone is usually
a change in gene expression
what determines whether a particular cell is able to respond to a hormone?
a. the presence of a specific hormone receptor
b. the location of the cell
c. the structure of the hormone
d. the gland that releases the hormone
a. the presence of a specific hormone receptor
where is the pituitary gland attached to?
what is it composed of?
- hypothalamus
- anterior and posterior lobes
which lobe of the pituitary gland is made of neural tissue
posterior pituitary
which lobe of the pituitary gland is made of glandular tissue
anterior pituitary
the ____ pituitary lobe stores and releases hormones that are made in the hypothalamus
posterior
the ____ pituitary lobe makes and releases hormones under regulation of the hypothalamus
anterior
which pituitary lobe makes its own hormones
anterior
how are hormones stimulated and released from the anterior pituitary?
hypothalamus releases a hormone into the blood and reaches the anterior to release its hormones
how are hormones stimulated and released from the posterior pituitary?
since hypothalamus and posterior pit. are made of neural tissue, hypo, uses action potentials to send a signal down an axon to the posterior lobe to release its hormone (which ultimately releases into the blood)
which two hormones are stored and released from the posterior pituitary gland
oxytocin
antidiuretic hormone (ADH)
how does oxytocin work
mechanoreceptors sense and it is a strong stimulant of uterine contractions and milk ejection
- positive feedback
how does ADH work
- osmoregulators in hypothalamus monitor solute concentration
- kidney tubules reabsorb more water to increase blood volume
anterior pituitary gland has a _______ connection to the hypothalamus
vascular
all hormones released by the anterior pituitary gland are _____ class
peptide
all the hormones released by the anterior pituitary gland activate the cyclic AMP 2ndary messenger systems at their targets EXCEPT
GH (growth hormone)
what is the function ACTH released by the anterior pit. gland
goes to adrenal glands to stimulate release of hormones like cortisol
what does it mean for a hormone to have a tropic effect
causes the target to release another hormone
what are the stressors in the short term response to stress
- injury
- temp. extremes
- extreme physical exertion
what occurs in the 1st phase of stress response (short term)
- fight or flight: adrenal medulla secretes epinephrine and norepinephrine in response to nerve signals
- glycogenolysis: triggers release of glucose and fatty acids into the blood (from liver)
- increase heart rate and respiratory rate
in the stress response, why is the release of glucose and fatty acids triggered (glycogenolysis)?
more glucose means more cell respiration=more ATP
what occurs in the 2nd phase of stress response
- hypothalamus–>CRH
- CRH goes to anterior pituitary
- anterior –> ACTH
- ACTH goes to adrenal cortex
- adrenal cortex releases cortisol
what is the effect of cortisol in the stress response
proteins and fats are broken down and converted to glucose–> leading to increased blood glucose
(gluconeogenesis)
what are chemicals that are released into the environment to attract mates or warn of danger
pheremones
which body system’s communication response is slower to take affect
endocrine
these kinds of hormones bind to membrane bound receptors
amine and peptide
what does the anterior pituitary gland hormone ‘TSH’ do
targets the thyroid gland
in sexual reproduction, what kind of sets of genetic material are combined
haploid (23 chromosomes)
- this makes a diploid organism (46 chromosomes)
specialized haploid cells are called ________, and they form a diploid ______
gametes
zygote
what is the form of asexual reproduction that involves an embryo growing without fertilization
parthenogeneis
what is the form of asexual reproduction that involves a female producing an embryo with ONLY her genes, but a male sperm activates it
gynogenesis
what are the pros of sexual reproduction
genetic diversity (recombination)
what are the pros of asexual reproduction
no mates needed and makes many cells
what is the con of sexual reproduction
egg must combine with sperm and that takes 2x as many cells
what are 3 ways mammals experience gestation
- marsupials : carry underdeveloped embryos in pouch
- monotremes: lay eggs
- placental: mothers carry fetus in uterus and its nourished by the placenta
what are the primary sex organs (gonads) of male and female
male: testes
female: ovaries
what are the function of gonads (2)
- produce sex cells (gametes) through meiosis
- secrete steroid sex hormones
what are the steroid sex hormones that gonads release in men and women
men: testosterone
women: estrogens and progesterone
why are the testis (which are enveloped in the scrotum) outside of the body
it is too hot in the body to sustain sperm alive
in males, what is the site of sperm production
testes
in males, what are the 2 functions of the testes
- produce sperm
- synthesize testosterone
in males, what is the function of the epididymis
sperm storage and maturation
in males, what is the function of the vas deferens
it transports sperm from the epididymis to the urethra
in males, how does sperm exit the penis through
the urethra (same place as urine exit)
where in the female reproductive system are:
- eggs produced
- the site of fertilization
- the site of embryonic development during gestation
- ovaries produce eggs
- fallopian tubes are site of fertilization
- uterus develops embryo
what are the two parts of the endometrial lining of the uterus
- stratum functionalis
- stratum basalis
which part of the endometrial lining of the uterus is shed during menstruation
stratum functionalis
which part of the endometrial lining of the uterus changes in response to ovarian hormone cycles
stratum functionalis
which part of the female reproductive system:
- serves as a barrier during pregnancy
- birth canal
- cervix
- vagina
what is it called:
- age at which reproductive organs become functional
- release of mature egg from the ovary
- egg and sperm unite
- puberty
- ovulation
- fertilization
what differs in how meiosis occurs in males vs females
timing and end product
how do testes know when to make sperm
at puberty, the hypothalamus starts to release GnRH to anterior pituitary and that stimulates release of gonad targeting hormones (FSH and LH)
what does FSH target in specific in males
Sertoli cells: releases ABP (androgen binding protein)
what does LH target in specific in males
Leydig cells: stimulates these to release testosterone
what does ABP released by Sertoli cells do
- androgen binding protein
makes spermatogenic cells receptive to testosterone
what does the acrosome in the head of the sperm contain
enzymes that allow sperm to burrow in fertilization
when do sperm acquire their fertilizing ability and forward motility properties
in epididymis (maturation)
- when are eggs produced in females
- why are eggs not fully matured as a baby
- start being produced in the womb (same eggs you have now are same you had at birth)
- prophase 1 of meiosis is frozen and resumes during puberty
what are the 3 phases of the ovarian cycle
- follicular phase
- ovulation
- luteal phase
what days of the ovarian cycle does the follicular phase occur in
days 1-14
(right after end of last cycle that resulted in no pregnancy)
events in the _______ influences the uterus
ovaries
- how is the follicular phase in the ovarian cycle started?
- what does the GnRH do next
- hypothalamus is stimulated to secrete GnRH in response to low estrogen
- stimulates anterior pit. to release FSH and LH
In ovarian cycle:
1. what does LH do after being stimulated by GnRH?
- what does FSH do after being stimulated by GnRH?
- LH: stimulates thecal cells to make estrogen precursor
- FSH: stimulates granulose cells to proliferate and make estrogen precursor from thecal cells into estrogen (active)
in follicular phase, what specific cell does LH stimulate?
FSH?
LH: thecal
FSH: granulosa
what is the ultimate result of the follicular phase (3)
granulosa and thecal cells multiply around developing oocyte
- and production of estrogen
- zona pellucida develops
when does ovulation occur in ovarian cycle
~day 14
the levels of estrogen produced in the follicular phase cause __________ of the hypothalamus from releasing from GnRH
inhibition
as granulosa cells activated and making active estrogen, eventually the levels cross the threshold and do what
positively feedback to hypothalamus and that results in SURGE of LH
the surge of LH during ovulation causes what
enzymes are released that cut the oocyte and close surrounding granulosa cells (corona radiata) out and its released
what happens to the leftover granulosa cells after oocyte and corona radiata are cut out during ovulation
develop into corpus luteum bc of LH
during follicular phase of the ovarian cycle, where estrogen is being produced, what happens meanwhile in the uterus
estrogen stimulates the regeneration of the stratum functionalis of the uterine lining
what days does the luteal phase of the ovarian cycle occur
~days 14-28
- what happens in the luteal phase of the ovarian cycle
- what happens in the uterus during this
- surge of LH from ovulation causes production of corpus luteum
- corpus luteum then produces progesterone - production of progesterone by corpus luteum promotes vessel production and maintain it too
if fertilization does not occur, what happens
corpus luteum degenerates into corpus albicans and decreased levels of estrogen and progesterone causes uterus lining to shed –>menstruation
if fertilization does occur, what happens
hCG is produced and keeps corpus luteum alive until placenta is formed
which of the following factors contributes to the occurrence of menstruation
1. high levels of hCG
2. low levels of hCG
3. decreased levels of estrogen and progesterone
4. low levels of FSH and LH
a. 1,3,4
b, 2,3,4
c. 1 and 3
d. 2 and 3
d. 2 and 3
what is the correct steps of the LONG term stress response
a. CRH goes to hypothalamus
b. Adrenal cortex releases cortisol
c. ACTH goes to the kidney
d. Anterior pituitary releases ACTH
e. Cortisol suppresses immune and reproductive system
a, d, c, b, e
larger animals have longer or shorter gestation periods
longer
what is the term fecundity
- when are humans most fecund?
the natural ability to produce offspring
- in their 20’s
which form of fertilization is mostly aquatic
external fertilization
what are the 4 factors that influence sperm movement in the uterus to fallopian tubes
- uterine contractions
- fallopian tube regulation
- capacitation
- chemical cues
what occurs during fallopian tube regulation that influences sperm movement
help propel sperm with uterine muscle contractions and ciliary activity
how does the time that fertilization can occur get prolonged
sperm releases rounds to not send all sperm at once
what is the process of capacitation in sperm
- why does it do it
“gunk” coat is removed prior to fertilization
- to increase sperm motility and hyperactivity and to expose receptor sites to the zona pellucida
when the sperm finally meets the egg, what are the stream of events that occur (6)
- sperm makes contact with the egg
- acrosome on the sperm reacts with the zona pellucida (releases enzymes to burrow)
- acrosome makes way into pervitelline space (reacts with enzymes )
- sperm enzymes activate protein receptors on egg that release enzymes to harden the membrane to prevent polyspermy
- plasma membranes of egg and sperm fuse
- sperm nucleus enters egg
what is the acrosomal reaction during fertilization
enzymes in the acrosome react with the zona pellucida to digest the coat to burrow into the egg
how is polyspermy prevented during fertilization
cortical reactions cause the cortical granules to release enzymes that harden the membrane to remove the sperm receptors
how is exactly is the cortical reaction caused by
smooth ER in the oocyte releases Ca2+ which then stimulates exocytosis of enzymes from cortical granules
after fertilization, what happens to the outer granulosa cells (corona radiata)?
are removed so the egg can fit through the fallopian tube into the uterus
Sperm have the best chances of getting to the secondary oocyte if:
1. they are the fastest sperm in the lot
2. they undergo capacitation
3. they pick up and respond properly to chemical cues secreted by the ovulated oocyte
4. uterine/vaginal contractions are induced within the female
a. 1, 2 ,3 and 4
b. 2, 3, and 4
c. 2 and 3
d. only 4
b. 2, 3, and 4
Which of the following is NOT a result of fertilization
a. intracellular Ca2+ concentration declines
b. the sperm and egg nuclei unite
c. the zygote becomes impermeable o more sperm as a result of cortical reaction
d. the corona radiata is removed to make the zygote small enough to fit through the fallopian tube
a. intracellular Ca2+ concentration declines
is cell proliferation brought on by mitosis or meiosis
mitosis
during embryogenesis, what happens to the zygote after fertilization first
undergoes cell proliferation (rapid mitosis and growth) into a blastocyst
what is the process when cells determine what kind of cell it will be
differentiation
what are the 3 germline cells
endoderm
mesoderm
ectoderm
all cells have the same genes, so what differs is not their genetic makeup , but _____________
their gene expression (on or off)
what is the process that causes an organism to develop its shape
morphogenesis
while the zygote is proliferating through mitosis, this forms a ______, which is hollowed out, and then inward growth (invagination) is the process of _____________
blastula
gastrulation
during __________, the three germ layers are formed
gastrulation
what is embryonic diapause
developmental arrest of the embryo by arrest of blastocyst growth and metabolic activity
which germ layer does the nervous system come from
ectoderm
what comes after gastrulation
neuralation
what happens during neuraltion
formation of the neural tube by folding of the ectoderm of neural plate
what are somites
blocks of mesoderm on the sides of the neural tube that give rise to segmental structures
what are the roles of the placenta (4)
- provides nutrition
- waste removal
- exchange of materials between mother and baby
- secretes estrogen and progesterone to support pregnancy
do the mother and baby’s blood mix in the placenta
no- things exchanged through diffusion and active transport
A sheep oocyte in a dish is injected with calcium. What will happen as a direct result of this?
a. the oocyte will becomes more permeable to sperm
b. the cell would undergo rounds of mitosis
c. the cell would undergo rounds of meiosis
d. sperm would no longer be able to fertilize the oocyte
d. sperm would no longer be able to fertilize the oocyte
when is the only time hCG is high in a pregnant female
1st trimester
why are gap junctions made in the muscle layer of the uterus ?
so the muscle cells can contract at once, to make birth easier
what role does melatonin play in birth
makes uterus more receptive to oxytocin and helps expression of gap junctions
________ is a lack of resistance to a disease
susceptibility
________ is the ability to ward off a disease
immunity
what are the immune system’s 2 categories
innate and adaptive
which category of immune defense is the first line of defense?
does this line of defense have a memory
-Innate
- does NOT have a memory (skin doesnt have memory)
what are the 3 big first line of defense mechanisms
- skin
- mucous membranes
- secretions of the skin
why is the skin a first line of defense against pathogens (3)
- epidermis (outermost layer) is very dry, not hospitable
- keratin in dead skin cells make the skin mechanically tough and resistant to bacteria
- fatty acids on skins surface create a dry, salty, and acidic environment
what is the role of lysozymes in sweat, tears, and saliva
destroys bacterial cell walls
- which category of immunity is the 2nd line of defense
(innate or adaptive) - does the second line of defense have memory?
- innate
- no
the 2nd line of innate defense includes _____ derived defenses
cell
what are the internal processes of the 2nd line of immune defense
inflammation, fever, phagocytosis
what is the process of diapedesis in the immune defense
cells squeezing through the capillary wall out of the blood into the targeted tissue
what is ameboid movement in the immune defense
motion of cells in the immune defense
what are chemotaxis in the immune defense
detect the direction and intensity of an extracellular chemical gradient, and migrate toward the source of stimulus
where do the cells in the innate immune system come from
red bone marrow
In inflammation response, how are phagocytes introduced into an area with tissue damage/ bacteria
histamine is released which causes vasodilation
- veins become leaky so phagocytes can squeeze through (diapedesis)
in the inflammatory response, how can phagocytes detect bacteria
via chemotaxis and move towards it thru ameboid movement
what happens once phagocytes are adhered to target bacteria in inflammatory response
phagocytes consume bacteria and tissue heals
why does body temperature increases when there are bacteria/ pathogens in the body and the immune response is triggered?
heat increases metabolic rate of enzymes and degrades the pathogen’s enzymes
what are ways the body induces a fever
vasoconstriction, deactivation of sweat glands, shivering
what is specific is introduced for the body to trigger a fever
pyrogens trigger prostaglandin synthesis, which increases body temperature
what are the 2 kinds of adaptive immune defenses
- cell-mediated
- humoral mediated
what kind of cells in the adaptive immune response are involved in the cell-mediated response
T cells
what kind of cells in the adaptive immune response are involved in the humoral-mediated response
B cells
what are lymphocytes
type of WBC
where do T and B cells develop
red bone marrow
where do T cells develop immunocompetence
in the thymus (transported there from the bone marrow)
where do B cells develop immunocompetence
stays in the bone marrow
when are T and B cells immunocompetent
activated with antigens and then circulate through the bloodstream
how can a B cell make antibodies for a pathogen
it engulfs the antigen and uses as a template to make antibodies
what kind of B cells make the antibodies
plasma cells
what do the antibodies released by B cells do
act as a “tag” for phagocytes to kill them
what are the 3 different antigen presenting cells (APC)
- dendritic cells
- macrophages
- B cells
what are APCs function
A type of immune cell that boosts immune responses by showing antigens on its surface to other cells of the immune system.
do T cells make antibodies
no
when an APC attached to a helper T cell, what is triggered
cytokines are released from the helper T cell, and those cytokines bind to another T cell to make cytotoxic T cells which kill the cell
what do cytotoxic T cells do
stimulated by cytokines released by Helper T cells that release proteins that destroy infected cell
what are the 4 cardinal signs of inflammation
- redness
- heat
- swelling
- pain
what are redness and heat caused by in the inflammatory response
vasodilation
what is swelling caused by in the inflammatory response
leaky capillaries
what is the difference between spermiogenesis and spermatogenesis
spermiogenesis: maturation of sperm in epididymis
spermatogenesis: make sperm gametes in testes
