KNES 260 Final Review

what are the 3 classes of hormones?

peptide, steroid and amine

amine hormones are usually made of what?

tryptophan or tyrosine (amino acids)

How do peptide hormones travel in the blood and how do they exert their effect on the cell?

* travel freely in the blood
* cannot enter the cell unless they have a membrane receptor
* quick acting and short half life

How do steroid hormones travel in the blood and how do they exert their effect on the cell?

* needs to be bound to a protein to travel in blood
* they are lipophilic, therefore can enter target cell
* slow acting and longer half life

What is a steroid hormone made of? Give an example of a steroid hormone

cholesterol

* examples: cortisol, estrogen and testosterone

What are three things that can affect hormone secretion?

stress, diet/sleep, emotional/disease state

what is permissiveness? give an example

the need of a second hormone to get the full expression of the hormone

* example: TH increases the number of receptor sites for epi

what is synergism? give an example

multiple stimuli

* ex: glucagon + epi + cortisol

what is a tropic hormone? give examples

act on other endocrine glands to control hormone secretion

* ex: hypothalamus and anterior pituitary

what is a non tropic hormone? give examples

act on effector organs

* ex: thyroid, adrenals, pancreas

what is primary hypersecretion caused by?

abnormality within the gland

what is secondary hyposecretion?

when the gland is normal, but there is a lack of hormonal secretion due to decreased tropic hormone

what is the role of the hypothalamus in endocrine function?

controls the anterior pituitary which then controls endocrine glands

what is another name for neurohypophysis and adenohypophysis?

posterior pituitary and anterior pituitary respectively

name 2 hormones that the posterior pituitary secretes and what are their effects?

* oxytocin and ADH
* oxytocin stimulates uterine contractions in childbirth and promotes milk ejection, overall helps promote attachment between mother and child
* ADH increases pressure in blood by increasing blood volume, increases water reabsorption in kidney to conserve fluid and maintain BP and BV

What are the 5 tropic hormones from the Anterior Pituitary? What is the non-tropic hormone from theanterior pituitary? What is the action of each of these hormones?

* tropic: FSH, LH, GH, TSH, ACTH
* non tropic: prolactin
* FSH: promotes egg and sperm production
* LH: estrogen and testosterone secretion, ovulation
* TSH: promotes TH secretion
* ACTH: promotes cortisol secretion
* GH: causes insulin growth like factors, stimulates protein synthesis and cell division to increase muscle and lengthen/thicken bones
* prolactin: promotes breast development and milk production

what triggers growth? name the 2 hormones involved

genetics, diet and sleep, normal levels of growth influencing hormones

* GHRH & GH

what do somatomedins do? what's another name for this hormone?

* stimulate cartilage growth and insulin like growth factors
* GH

what are the effects of excessive growth hormone in adults?

* Gigantism or Acromegaly occurs
* Gigantism: occurs before growth plates close; lengthening of bone
* Acromegaly: occurs after growth plates close (20 yrs); thickening of bone

what is the function of melatonin?

influences circadian rhythm and antioxidant activity (repair work)

what 2 hormones come from the thyroid gland and what are their effects?

* TH and calcitonin
* TH: increases metabolism, therefore, increasing heat
* calcitonin: decreases blood calcium levels

what is needed for thyroid hormone production?

iodine

when is thyroid hormone released?

when cold as TH increases heat

what is Grave's disease? what are the treatment options?

* hyperthyroidism - excessive thyroxine
* it is an autoimmune condition
* can be treated by medication, radiation and surgery

what is hyperthyroidism? and what are some symptoms?

* excessive thyroxine
* tachycardia, hyperactivity, weight loss, hunger, hot, bulgy eyes

what is exophthalamus?

bulgy eyes

what is hypothyroidism? what are its causes and symptoms?

* low TH
* caused by: auto immune, low TSH, low iodine
* \

what is cretinism?

* low TH in first 2 years of life
* severe mental impairment, low muscle tone, sleepiness

what is a goiter? what causes it?

* enlargement of thyroid

what 2 hormones control calcium balance and how do they exert their effects?

* calcitonin and parathyroid hormone
* calcitonin is released if blood calcium levels are too high, to decrease it (decreases calcium absorption in gut, increases calcium excretion in kidney, increases calcium absorption in bones)
* parathyroid hormones are released if blood calcium levels are too low, to increase it (increases calcium absorption in gut, decreases calcium excretion in kidney, calcium is released in bones)

what is the role of vitamin D in calcium balance? how is PTH involved?

stimulates calcium absorption from intestine

* is activated by PTH

what causes rickets?

lack of vitamin D or calcium

what are the effects of aldosterone? when is it secreted?

acts on renal tubules in kidney which speeds up the Na+/K+ pump; increases Na+ and water reabsorption

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low aldosterone results in what disease?

Addison's disease

name 3 hormones from the adrenal cortex

mineralcorticoids (aldosterone), glucocorticoids (cortisol), androgens

what hormone comes from the adrenal medulla?

epinephrine

what are the effects of cortisol? when is it secreted?

* increases blood glucose, stimulates protein break down in muscle, facilitates lipolysis, anti inflammatory and immunosuppressive effects
* waking up, during exercise or stressful events (resistance phase/second phase in stress response)

what is pheochromocytoma? what are its symptoms?

* tumor of adrenal medulla which increases epinephrine and norepinephrine

what hormones are involved in the stress response?

epinephrine, norepinephrine, cortisol, TH, hGH,

what 2 hormones control sugar levels and how? where are these hormones from?

* insulin and glucagon
* insulin decreases blood sugar by moving glucose into the cells and forms glycogen; produced by beta cells
* glucagon increases blood sugar by gluconeogenesis (formation of glucose from amino acids), glycogenolysis (breakdown of glycogen), ketogenesis (formation of ketones via chemical processes)
* produced by alpha cells
* both are secreted by the pancreas

What hormone dominates in the absorptive and post-absorptive states?

insulin and glucagon respectively

What are the effects of insulin?

decreases blood sugar by moving glucose into cells and creating glycogen

* promotes cellular uptake

What are the effects of glucagon?

increases blood sugar

What is diabetes mellitus, its cause and effects? What are the symptoms?

* high blood sugar in urine and high urine volume
* caused by low insulin or low insulin response
* effects are long term tissue damage, diabetic retinopathy, kidney damage, heart disease
* frequent urination, thirst, hunger

How do type I and type II diabetes differ from each other? How do you treat each?

* type 1 is caused by low insulin, is an autoimmune disorder, affects younger people
* type 2 is caused by low insulin response, gradual onset, more common in adults
* type 1 is treated by daily injections of insulin, diet control and blood monitoring
* type 2 is treated by diet and exercise

What are the effects of estrogen and testosterone? Where are they secreted?

* estrogen: menstrual cycle, increased fat, increased water, breasts, bone deposition and mucous
* testosterone: sperm production and secondary sex characteristics
* estrogen are secreted by the ovaries. testosterone are secreted by the testes

what is the role of FSH in male and female?

* male: controls production of sperm
* female: controls menstrual cycle and stimulates growth of eggs

what is the role of LH in male and female?

* male: causes Leydig cells of testes to produce testosterone
* female: triggers the creation of steroid hormones from overies

how are spermatogenesis and oogenesis different in terms of time?

* spermatogenesis: can be accomplished within 2 months
* oogenesis: can take anywhere from 12-50 years to finis on a cyclic basis from onset of puberty till menopause

how are spermatogenesis and oogenesis different in terms of how much it can produce?

spermatogenesis: postpubertal male can produce several hundred million sperm each day

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oogenesis: female born will be limited, largely non renewable supply of germ cells

how are spermatogenesis and oogenesis different in terms of its yield?

spermatogenesis: each primary spermatocyte yields 4 equally viable spermatozoa

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oogenesis: each primary oocyte yields only one cytoplasm rich ovum and three cytoplasm poor polar bodies that disintegrate

Where does sperm production occur (cell and structure)?

in the testes - Leydig cells and seminiferous tubules

Name the three accessory glands

seminal vesicles, prostate gland, bulbourethral gland

What does the seminal vesicles secrete? How does it aid the sperm?

* fructose, alkali, prostaglandins
* fructose to nourish sperm
* alkali to neutralize vaginal acid
* prostaglandins for vaginal contractions

What does the prostate do?

secrete thin, milky, alkaline fluid that helps sperm viability

What do the seminiferous tubules do?

production, storage and maturation of sperm

What is the normal sperm count in an average ejaculate?

400 million

Name a male fertility problem

blocked tubules, decreased sperm quality or quantity, decreased accessory gland secretion

What is the function of the scrotum?

keep the testes at the best temperature for sperm production

Name two locations of sperm storage

vas deferens and epididymis

What are the functions of the Sertoli cells?

acts as a blood testis barrier, assist sperm production, secrete seminiferous fluid, aids Leydig cells to secrete testosterone, secretes inhibin which inhibits FSH

How many days does it take for sperm production?

64-74 days to maturation

What is the average sperm production per day?

200 million

What are the structures of the mature sperm?

Tail, DNA head, acrosome and mitochondria

Name the two phases of the ovarian cycle. what occurs in each cycle?

* follicular phase and luteal phase
* follicular phase: day 1-14, maturation of follicles due to higher FSH, secretes estrogen
* luteal phase: day 14-28, remaining follicular cells (corpus luteam) either prepares for fertility or not. if it is not fertile, your period occurs, secretes estrogen and progesterone

Name the 3 phases of the uterine cycle - what is occurring in each?

* menstrual, proliferative, secretory/progestational
* menstrual: day 1-7, shedding of functional layer, triggered by a drop in estrogen and progesterone
* proliferative: day 7-14, higher estrogen, repairs uterine wall
* secretory/progestational: high estrogen and progesterone, endometrium thickens in readiness for implantation

Where is the site of egg fertilization?

ovarian/fallopian tubes

Where does follicle development occur in women and in what days of the cycle?

occurs in ovary at ovulation (day 14)

What does the corpus luteum do?

secretes estrogen and progesterone

What does the corpus luteum do if the egg is not fertilized?

it degenerates, causing a drop in estrogen and progesterone, causing the endometrium to shed

What does the corpus luteum do if the egg is fertilized?

secretes hCG, which causes the corpus luteum to be maintained, maintaining secretion of estrogen and progesterone

What are the uterine layers and which is shed each month with a woman's period?

endometrium, myometrium, serosa/perimetrium

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Endometrium is shed

What hormone changes cause menstruation each month?

secretion of progesterone and estrogen, then drops

What hormone is secreted to maintain the endometrium during pregnancy?

progesterone

Name a female fertility problem

abnormal production of FSH/LH, irregular menstrual cycles, endometriosis, vagina too acidic, pelvic inflammatory disease, aging, blocked tubules

What occurs with endometriosis?

endometrial tissue grows outside of the uterus, such as the ovaries, fallopian tubes, etc

Name two things the vagina secretes and why?

* mucous to aid sperm survival
* acid to protect the vagina from bacteria

What is the role of the fimbrae?

they draw ovum into fallopian/ovarian tubes

What is the function of the follicular cells?

Secrete thyroid hormone (thyroxin)

What is ovulation and what day of the cycle does it typically occur on?

a phase in the menstrual cycle where an egg/ovum is released from one of the ovaries due to a spike in FSH and LH

* day 14

How does the ova move within the fallopian tubes?

cilia and smooth muscle

When does oogenesis occur?

From a female's time in the womb before birth

At what day does implantation occur?

day 6-7

When does the placenta become functional?

5 weeks

When does the heart start to beat?

5 weeks gestation

When does organ development (organogenesis) occur? What stage does major growth occur?

week 3-8

* fetal growth period

What are some body changes seen in Mom during pregnancy?

* uterine enlargement, breasts enlarge, BV increases by 30%, weight gain, respiratory activity increases by 20%, urinary output increases
* faster heart rate, greater stroke volume, lower and upper intestines moved up, etc

What are the 3 phases of delivery?

cervical dilation, delivery of baby, delivery of placenta

What are some complications during pregnancy?

ectopic pregnancy, miscarriage

What occurs with hyperemesis gravidarum?

excessive vomiting during pregnancy

Why do neural tube defects occur?

due to folic acid (form of vitamin B9, needed for cell division, RBC production, etc) deficiency

What are some congenital (structural/functional) defects that occur during pregnancy?

conjoined twins, cleft lip/palate, congenital rubella syndrome (CRS - malformations of fetus), fetal alcohol syndrome (FAS)

What substances are reabsorbed in the kidney?

sodium, chloride, calcium, phosphate, water, glucose

What is renal clearance?

the rate at which a solute disappears from the body. it is a non invasive way to measure GFR (glomerular filtration rate)

What substances are secreted by the kidney?

potassium, hydrogen, large organics

Name the three processes involved in urine production.

Glomerular filtration, Tubular reabsorption and Tubular secretion

Why are RBC's not normally found in the urine?

glomerular filtration allows fluid into the tubule, such as electrolytes, water and glucose. however, RBCs and proteins are too large to be filtered

Name two functions of the urinary system.

excretion of wastes, water balance, blood pressure control, acid base balance, blood cell production, vitamin D activation

What is plasma (glomerular) colloid osmotic pressure? Does it support or oppose filtration?

it is a force involved in glomerular filtration. it opposes filtration

What is Bowman's capsule hydrostatic pressure? Does it support or oppose filtration?

it is a force involved in glomerular filtration. it opposes filtration