Phys Final

Front 1

(1) Digestion

Back 1

mechanical and chemical breakdown of foods

Front 2

(2) Absorption

Back 2

transfer of substances from gastrointestinal (GI) tract to extracellular fluid (ECF)

Front 3

(3) Secretion

Back 3

Transfer of water/ions from ECF to GI tract; also release of products of GI epithelial cells

Front 4

(4) Motility

Back 4

movement of material through GI tract via smooth muscle contractions (mostly)

Front 5

digestive tract

(basic 3 facts)

Back 5

1. one long tube

2. muscular walls lined with epithelium

3. skeletal muscle sphincters close off each end

Front 6

Mouth

(oral cavity)

Back 6

mechanical and chemical breakdown of food (digestion) begins here via:

1. mastication

2. saliva

Front 7

Pharynx

(throat)

Back 7

common path-way for air and food/liquid:

1. air to larynx, trachea

2. food/liquid to esophagus

Front 8

Esophagus

Back 8

muscular tube with both skeletal and smooth muscle; takes food to stomach

Front 9

stomach

Back 9

1.mechanical digestion

--smooth muscle contraction

2. chemical digestion

--gastric secretions

3. food + gastric secretions = Chyme

Front 10

pyloric sphincter

Back 10

-releases chyme into small intestines

-controls rate of food released for digestion and absorption

Front 11

small intestines

Back 11

1. primary site of digestion (chemical)

2. primary site of absorption

--nutrients, H2o, vitamins, minerals

Front 12

3 major regions of small intestines

Back 12

1. Duodenum (1ft)

2. Jejunum (3-4ft)

3. Ileum (4-5ft)

Front 13

duodenum

Back 13

1. chyme mixed with pancreatic secretions

--digestive enzymes, bicarbonate

2. chyme also mixed with bile

Front 14

jejunum

Back 14

1. digestions/absorption usually done here

Front 15

ileum

Back 15

1. continued digestion/absorption capability;

2. transport to colon

Front 16

(1) Mucosa layer

(inner most)

Back 16

Composition:

1. epithelial cells

2. immune cells (GALT)

3. thin layer of smooth muscle

Absorptive

1. villi

2. contraction of smooth muscle

Secretory

1. enzyme, mucus (goblet cells) into lumen

Epithelial somatic stem cells

1. produce new epithelium

2. susceptible to cancer

-Cell-to-cell junctions are leakier here than in stomach

-leakiness can be regulated

Front 17

(2) Submucosa

Back 17

1. connective tissue layer

2. provides elasticity

3. large blood & lymph vessels to pick up what has been absorbed

4. major nerve network

--part of enteric nervous system

--regulates digestion

Front 18

(3) external muscle

Back 18

1. outer wall of GI tract

2. responsible for motility

3. Two layers of smooth muscle:

a. circular

---contraction decreases lumen diameter

b. longitudinal

--- contraction shortens GI tract

4. the second nerve network of enteric nervous system

Front 19

(4) serosa

Back 19

1. outer covering of the entire digestive tract

2. connective tissue

3. lubrication against other organs

Front 20

large intestine

(colon)

Back 20

1. digestion and absorption are mostly complete

2. recovery (absorption) of remaining water

--turns chyme into a semisolid mixture of indigestible material called feces

Front 21

ileocecal sphincter

Back 21

regulates chyme flow from small to large intestine

Front 22

migrating motor complex

Back 22

1. between meals

2. series of contractions from stomach to large intestine

3. moves food remnants and bacteria from upper GI tract into large intestine

Front 23

peristalsis

Back 23

1. after meal

2. waves of contraction from section to section

3. circular muscle contracts just behind a bolus of food

Front 24

segmental contractions

Back 24

1. short segments contract and relax

2. mixes food and keeps it in contact with epithelium

Front 25

Rectum -> anus

Back 25

1. internal anal sphincter: smooth muscle

2. external anal sphincter

Front 26

salivary glands

Back 26

1. paired glands (6 total) --> major glands

2. secrete saliva: h2o+enzymes+mucus

--immune function (IgA)

3. primarily parasympathetic control, some sympathetic control

4. stress reduces salivary production

Front 27

pancreas

Back 27

1. both an endocrine & exocrine gland

a. exocrine portion: secretes enzymes into small intestine

b. endocrine portion: produce hormones

Front 28

acinar cells

(pancreas)

Back 28

1. exocrine

2. release secretions into ducts that lead into the pancreatic duct

Front 29

islet cells

(pancreas)

Back 29

1. endocrine

2. make hormones e.g. insuline

3. have a vascular supply (capillaries)

Front 30

liver

Back 30

1. bile secretion (stored in gallbaldder)

2. metabolism of nutrients

3. removal of old RBCs and bacteria from blood

4. breakdown of toxins

5. plasma protein synthesis

6. activation/breakdown of hormones

Front 31

Bile

Back 31

1. helps digest fats

2. ____ breaks down blobs

3. lipase then digests the smaller blobs

4. co-lipase gets between ____ molecules to let lipase in to reach fat

5. gallbladder stores ____

Front 32

portal system

Back 32

moves absorbed nutrients to the liver:

1. capillaries in digestive tract

2. hepatic portal vein

3. liver

Front 33

capillaries in liver do what 3 things?

Back 33

1. remove toxic compounds

2. break down some molecules

3. simply pass on others

Front 34

haptic vein goes to were?

Back 34

the vena cava

Front 35

Digestive systems defenses

Back 35

1. digestive enzymes

2. mucus

3. acid

4. Lymphoid tissue (GALT)

5. Diarrhea

6. Vomiting

Front 36

Diarrhea

Back 36

pathological state in which intestinal fluid absorption is disrupted, resulting in watery feces

Front 37

Psychosomatic diarrhea

Back 37

stress induced, due to an increased intestinal motility

Front 38

Osmotic diarrhea

Back 38

when unabsorbed solutes prevent water absorption (e.g. lactose, olestra, laxatives)

Front 39

Secretory diarrhea

Back 39

pathogen-induced; adaptive unless prolonged

1. 4million people worldwide die each year

2. 200,000 kids hospitalized in U.S. each year

Front 40

Vomiting

Back 40

1. =emesis

2. protective

Front 41

sensory inputs that cause emesis (3)

Back 41

1. psychological

2. chemoreceptors detect pathogens in GI tract

3. disturbed equilibrium (e.g.) motion sickness

Front 42

Medulla oblongata (brainstem) initiates what? (3)

Back 42

1. muscle contractions from small intestines upwards (reverse peristalsis)

2. abdominal muscles contract

3. stomach relaxes, forces contents into esophagus and out mouth

Front 43

Enteric Nervous System

Back 43

1. nervous + endocrine system

2. autonomic nervous system = sympathetic, parasympathetic,

Front 44

enteric nervous system characteristics (4)

Back 44

1. Mostly independent

2. in the GI tract

3. regulates motility, secretions of digestive enzymes and gastric acid

4. does the actual work of digestion

Front 45

GI tract regulations (3)

Back 45

1. Long reflexes

a. sight, smell, sound, though of food = stimulus

b. prep for meal: saliva and gastric acid production

2. Emotions

a. butterflies in your stomach

b. fight-or-flight reactions

3. Taste receptors in gut

a. endocrine and exocrine responses differ for different foods

b. G-protein-coupled receptors that are found in taste buds are also found in some epithelial cells in gut

Front 46

hyena reproductive tract morphology

Back 46

1. Enlarged clitoris - "peniform clitoris"

2. Due to high androgen exposure during development

3. Hanging clitoris is a social signal

4. A lot of females die during birth

Front 47

Sequential Hermaphroditism

Back 47

Are able to change sex

1. clownfish are always born male first

2. if social environment needs it, a male will change into a female

Front 48

True hermaphrodite

Back 48

have both sex organs

1. marine flatworms

2. engage in "penis-fencing"

Front 49

Male Gonads

Back 49

testes (singular = testis)

Front 50

Testes

Back 50

1. full of tubes -- seminiferous tubule

2. As sperm gets closer to lumen, the sperm in more mature by sertoli cells

3. Androgen (testosterone) production by Interstitial (leydig) cells

Front 51

scrotum

Back 51

1. houses testes external to body cavity at slightly lower temperature than body temp

2. necessary form sperm production

Front 52

Dartos & Cremaster muscles

Back 52

can bring the testes closer or further away from the body

Front 53

epididymis

Back 53

site of final sperm maturation

Front 54

vas deferens

Back 54

joins urethra via ejaculatory duct in prostate gland

Front 55

Reproductive function of penis

Back 55

1. deposit sperm into female reproductive tract

2. normally flaccid; accomplishes penetration via erection

Front 56

What causes erection reflex?

Back 56

1. Increase in parasympathetic innervation to penis

2. artery/arteriole dilation

3. increased blood volume in erectile tissue

4. physical compression of veins

5. erection

Front 57

Components of Semen (8)

Back 57

1. sperm: gametes

2. mucus: lubricant

3. water: provide liquid medium

4. buffers: neutralize acidity of vag

5. nutrients: nourish sperm

6. enzymes: clot semen in vagina, then liquify

7. zinc

8. prostaglandins: may aid sperm transport

Front 58

circumcision

Back 58

1. ~70-80% of males worldwide are UNcircumcised

2. performed for religious/cultural reasons

3. In US, current circumcision rate <50%

4. historically done to reduce amount of masturbation

Front 59

Female reproductive phys characteristics

Back 59

1. cyclic changes in activity (menstrual cycle),

2. restricted time periods of fertility (related to ovulation)

3. limited gamete (ege) production (~400 eggs ovulated)

4. capacity for pregnancy, birth

Front 60

female gonad

Back 60

ovary (plural = ovaries)

Front 61

Follicle

Back 61

each contains a single ovum (plural = ova) or egg (gamete)

Front 62

Granulosa cells

Back 62

gamete development

Front 63

Theca cells

Back 63

produce androgens; converted to estrogen by granulosa cells

Front 64

uterine tubes

(fallopian tubes, oviducts)

Back 64

1. receive ovulated egg from ovary

2. site of fertilization

3. connected to uterus

Front 65

uterus

(womb)

Back 65

1. hollow, muscular, extensible organ

2. site of implantation (usually)

3. houses developing embryo

Front 66

Ectopic pregnancy

Back 66

1. implantation outside of the uterus

2. ~1 in 75 conceptions; almost never viable

Front 67

cervix

Back 67

1. connects uterus to vagina

2. contains endocervical glands that secrete mucus - protective function

3. mucus -- variable across menstrual cycle --> usually thick & acidic, but becomes thinner, more basic around ovulation

Front 68

Vagina

Back 68

1. canal that conncects external genitalia to cervix of uterus

2. lining coated in acidic mucous - also protective

3. receives penis during copulation (intercourse)

4. serves as birth canal

Front 69

labia majora/minora

Back 69

outer, inner skin folds

Front 70

clitoris, clitoral hood (prepuce)

Back 70

erectile tissue, sensory nerves

Front 71

vestibule

Back 71

region enclosed by labia minora

Front 72

vestibular glands

Back 72

on either side of opening to vagina; lubrication (bartholin's glands)

Front 73

pulsatile

Back 73

released at beginning in puberty

Front 74

male (1) excitement

Back 74

1. erotic stimuli (psychological and/or physical)

2. penile erection (parasympathetic NS)

Front 75

male (2) plateau

Back 75

1. increasing blood pressure, HR, respiratory rate, pleasurable sensations

Front 76

male (3) orgasm

Back 76

1. rhythmic muscular contractions that produce ejaculation:

--expulsion of semen (sperm + seminal fluid) out of penis

2. sympathetic NS

*average sperm count = ~100 million sperm/mL

Front 77

male (4) resolution

Back 77

1. relaxation (refractory period for erection/ejaculation)

Front 78

Ovulation

Back 78

1. follicle secretes collagenase

2. follicle/ovarian wall dissolved

3. triggers inflammatory response

4. leads to rupture

Front 79

menstruation

Back 79

1. shedding of uterine lining in absence of implantation

2. d1 = start of ___; ~d14 = ovulation

3. driven by hormonal changes from hypothalamus, anterior pituitary, and ovary

4. repeats in absences of pregnancy

Front 80

Menarche

Back 80

initial onset of menstruation (reproductive competence)

Front 81

menopause

Back 81

permanent cessation of menstruation

Front 82

what is the trigger for ovulation?

Back 82

the LH surge

Front 83

proliferative phase

Back 83

1. regrowth of endometrial tissue in preparation for potential pregnancy; in response to estrogen

Front 84

secretory phase

Back 84

1. uterine secretions of fluids rich in glycogen (energy for developing embryo;

2. late secretory phase --> cervical plug: maintained by estrogen and progesterone

Front 85

menses

(menstrual phase)

Back 85

1. shedding of uterine lining due to decline of estrogen and progesterone ("period")

2. 3-7 days

3. 75 mL

4. plasmin

Front 86

female (1) excitement

Back 86

1. erotic stimuli (psychological and/or physical)

2. vaginal lubrication

3. clitoral tissue erection (parasympathetic NS)

Front 87

female (2) plateau

Back 87

1. increasing blood pressure

2. HR

3. respiratory rate

4. pleasurable sensations

Front 88

female (3) orgasm

Back 88

1. rhythmic muscular contractions of vagina and uterus

2. NOT necessary for conception, sympathetic NS

Front 89

female (4) resolution

Back 89

1. relaxation

Front 90

sperm capacitation

Back 90

1. necessary for fertilization - occurs in female tract

Front 91

acrosomal reaction

Back 91

1. acrosome content is released to get to egg membrane

Front 92

cortical reaction

Back 92

1. as soon as a sperm binds, it prevents other sperm from binding to egg

2. prevents polyspermy

Front 93

Implantation

Back 93

1. ovulation

2. day 1. fertilization

3. days 2-4. cell division

4. days 4-5. blastocyst reaches uterus

5. days 5-9. blastocyst implants

Front 94

zygote

Back 94

1. fused egg & sperm

2. totipotent prior to implantation (total potential)

3. inner cell mass is pluripotent

Front 95

How to prevent menses?

Back 95

1. placenta keeps corpus luteum from degeneration via hCG

--continued progesterone, estrogen, inhibin prodcution

2. After 2 moths, corpus luteum degenerates, and placenta makes its own progesterone to prevent menses

3. hCG peaks at ~3 months then slowly diminishes

Front 96

The Placenta

Back 96

1. dense vascular supplies

2. needed for hormone production

3. nutrient/wast transfer

4. continues to grow during pregnancy (~8" diameter at birth)

Front 97

colostrum

(lactation)

Back 97

1. initial secretion

2. low volume, low fat, low Ca+

3. High proteins, carbs

4. Maternal antibodies

5. stimulates GI tract (mild laxative)

Front 98

milk

(lactation)

Back 98

1. High fat

2. High lactose (also stimulates gut bacteria colonization & proliferation)

3. High Ca++

Front 99

lactation pathway

Back 99

Sensory

1. mechanoreceptors in breasts stimulate CNS of hypothalamus inhibits an inhibitor PIH (prolactin inhibitor hormone) (dope)

2. goes to anterior pituitary gland

3. causes prolactin increase; stimulates milk production

1. stimulates hypothalamus to produce oxytocin in posterior pituitary

2. smooth muscle contraction

3. milk ejection

Front 100

Estrogens/Progestins

(contraceptives)

Back 100

1. inhibit GnRH (therefor no FSH)

2. mimics pregnancy so no new follicles will be produced

Front 101

Progestins

(contraceptives)

Back 101

1. Thickens cervical mucus and prevents sperm movement

Front 102

1. genital tubercles

(males)

Back 102

forms head of penis

Front 103

2. urethral folds and grooves

(males)

Back 103

forms shaft of penis

Front 104

3. labloscrotal swellings

(males)

Back 104

forms shafts of penis and scrotum

Front 105

1. genital tubercles

(females)

Back 105

forms clitoris

Front 106

2. urethral folds and grooves

(females)

Back 106

1. form labia minora

2. opening of vagina

3. urethra

Front 107

3. labioscrotal swellings

(females)

Back 107

forms labia majora

Front 108

what makes a male a male in the womb?

Back 108

testosterone goes to DHT causes development of male external genitalia

Front 109

development of internal organs

(male)

Back 109

1. cortex: regresses

2. medulla: forms testis

3. wolfman duct: forms tubes of testicles; epididymis, vas defenaus, seminal vessicles

4. mollerian duct: regresses

Front 110

development of internal organs

(female)

Back 110

1. cortex: forms ovary

2. medulla: regresses

3. wolfman duct: regresses

4. mollerian duct: becomes fallopian tubes, uterus, and upper half of vag