digestive. kidneys, reproductive system

6 basic processes

Ingestion, secretion, motility, digestion, absorption, defecation

ingestion

taking food and liquids into the mouth

secretion

releasing of water, acid, buffers, enzymes into GI tract

Motility

mixing and propulsion of food through the GI tract

Digestion

mechanical and chemical breakdown of food

absorption

digested nutrients pass into blood and lymph

Defecation

elimination of waste products (feces)

4 layers of GI tract

mucosa, submucosa, muscularis, serosa

Peritoneum

double layered serous membrane

enteric nervous system

“brain of the gut”

• involuntary control of GI muscles and glands

• functions independently and with other autonomic branches

sympathetic digestion

decrease GI secretion and motility by inhibiting ENS neurons

parasympathetic nervous system

vagus nerve - increased GI secretion and motility by activating ENS neurons

Orexins

produced by hypothalamus

• promotes hunger/ eating behavior

Ghrelin

produced in the stomach

• increases GI motility, promotes hunger/eating behavior

leptin

produced by adipose tissue

• promotes hunger

insulin and glucagon

produced by the pancreas

• blood glucose homeostasis/ absorption

somatostatin

produced by D cells in gastric pits

• inhibits secretion of digestive enzymes in stomach, decrease GI motility

Gastrin

produced by G cells in gastric pits

Mastication

chewing, mechanical breakdown of ingested food

trigeminal nerve

chewing

facial nerve

taste

Hypoglossal nerve

moves food around

salivary glands

secrete fluid to clean mouth, begin digestion, and lubricate GI tract

Pharynx

• made of skeletal muscle

• When relaxed: pharynx patent; when contracted: assists in swallowing

• muscle contractions help propel swallowed food into the esophagus

epiglottis

closes over the larynx and prevents food from entering respiratory tract

swallowing

Glossopharyngeal nerve

esophagus

collapsable muscular tube, posterior to trachea, connects the pharynx to the stomach

peristalsis

contraction of circular muscles and longitudinal muscles pushes food into stomach

stomach

inferior to the diaphragm

functions: releases digestive enzymes, mixes ingested food with the enzymes, peristalsis, and store ingested food

lower esophageal sphincter

prevent reflux of food that has passed into stomach back into esophagus

Pyloric sphincter

distribute small amounts of stomach contents to small intestines

Gastric Mucous cells

secrete bicarbonate and mucous. creates a physical and chemical barrier, prevents stomach acid from damaging stomach lining

Parietal cells

secrete stomach acid (activates digestive enzymes and kills microbiomes)

secretes intrinsic factor (essential for vitamin b12 absorption in small intestines)

Chief cells

secretes pepsinogen (helps with protein digestion)

secretes gastric lipase (helps with lipid digestion)

D cells

secrete somatostatin a hormone that decreases digestion

G cells

secrete gastrin which increases digestion

accessory organs of the digestive system

liver, gallbladder, and pancreas

• synthesize and secrete exocrine substances crucial for digestion into first part of small intestines

Pancreas

endocrine = blood glucose homeostasis

exocrine = secretin and CCK

Liver

• synthesizes and secretes bile

• stores blood

• detoxification

• synthesizes plasma proteins

• vitamin k production

• stores excess iron and glycogen

• bilirubin metabolism

• lymphatic tissue and immune surveillance

• vitamin D activation

• synthesis of thrombopoietin

Gallbladder

stores and releases bile

small intestines

• absorption of most nutrients and water (water follows sodium)

hepatic portal circulation

all nutrients and toxins absorbed from the small intestines into circulation first pass through the liver for detoxification, nutrient storage, and immune surveillance before entering general circulation

segmentation contractions

move contents back and forth mixing them with digestive enzymes

Large intestine

absorbs small amounts of water and electrolytes

• dries contents and produces feces

parts of the large intestine

• cecum

• appendic

• ascending colon

• transverse colon

• descending colon

• sigmoid colon

ileocecal sphincter

junction between small and large intestines

internal anal sphincter

smooth muscle and involuntary

external anal sphincter

skeletal muscle and voluntary

what is the intracellular fluid made of

potassium

what is the extracellular fluid made of

sodium

what organ rids the body of excess water

the kidney

sodium: major ECF ion

• controls blood volume, water follows sodium

• kidneys conserve or excrete sodium to maintain water balance

potassium: major ICF ion

• muscle contractions; nerve conduction

• kidnneys regulate excretion of potassium

magnesium: bone matrix and vessel diameter

• excreted by kidneys

• “goes with” potassium

normal blood pH

7.35 - 7.45

buffer system

“buffers” acute pH change by binding free H+ ions

• bicarbonate is the primary ECF buffer

respiratory system

H+ ion concentrations in the blood by controlling the rate of CO2 removal

renal system

regulate H+ ion concentrations and HCO3- ion concentrations by controlling the rate of their excretion

ways to regulate pH balance

sensory: chemoreceptors monitor concentrations of o2, co2, and acid in blood

integrating center: respiratory center (regulates reflex breathing)

motor: breathing patterns change to eliminate or retain co2

Kidney functions

• filtering blood

• eliminating waste products of metabolism in urine

• fluid balance, pH balance, and electrolyte balance

• regulates blood pressure

• activates vitamin: bone health

• hormone production

Nephron

• functional units of the kidney

• individual units of filtration

  • remove nitrogenous waste products

  • balance

  • produce urine

glomerular filtration

blood plasma is filtered from blood stream into the first part of the nephron, the filtration is NOT selective

• BP and GFR are directly correlated

tubular reabsorption

cells in the renal tubule reabsorb water and solutes into the blood stream, is HIGHLY selective

tubular secretion

cells in the renal tubule secrete waste products, HIGHLY selective

afferent arteriole

transfers blood to nephron

glomerulus

filtration, ball of highly permeable capillaries

Bowmans capsule

“catches” filtered plasma

renal tubule

reabsorption and secretion of urine

proximal tubule

majority of Na+ and H2O reabsorbed

descending limb

h2O reabsorption only

ascending limb

ion reabsorption only

distal convoluted tubule and collecting ducts

reabsorb variable amounts of ions and H2O dependent hormones

Peritubular capillaries

reabsorb material from tubule lumen

Thirst center

hypothalamus

Atrial Natriuretic Peptide (ANP)

• promotes secretion of sodium in renal tubules which promotes excretion of water

Renin-angiotensin-aldosterone system (RAAS)

a hormone system that regulates long-term blood pressure, blood volume, and sodium balance.

• When blood pressure or kidney blood flow drops, the kidneys release renin, triggering a cascade that narrows blood vessels and forces the body to retain salt and water, ultimately increasing blood pressure.

parathyroid hormone (PTH)

low blood calcium levels stimulate the secretion of PTH which stimulates renal tubule to reabsorb more calcium into the blood

atrial Natriuretic peptide (ANP)

inhibit reabsorption of sodium and water

angiotensin II

promotes reabsorption of sodium and water

aldosterone

promotes reabsorption of sodium and water and excretion of potassium

Micturition

urination

gonads

organs that produce gametes

gametogenesis

the process of producing eggs and sperm

production of sex hormones

steroid hormones that promote gametogenesis and development of secondary sex characteristics

Gonadotropin-releasing hormones (GnRH) from hypothalamus

controls secretion of pituitary hormones for males and females

FSH hormone for testes

acts on sertoli cells to support sperm production and maturation

LH hormone for testes

controls production of testosterone

FSH hormone for ovaries

initiates and regulates oogenesis in the ovaries

LH hormone for ovaries

controls production of estrogen and progesterone

Y chromosomewhat chromosome determines sexual differentiation?

Y chromosome

scrotum

pouch of skin and subcutaneous tissue

cremaster muscles

skeletal muscles that contract and relax to maintain stable temps for sperm production

parts of the sperm

• acrosome: enzymes to aid in fertilization

• mitochondria: ATP production

• Flagellum:propulsion through female reproductive system

Epididymis

tightly coiled tube adjacent to testis

• where immature sperm continue to mature

• 65-75 days to mature

vas deferens

unites with seminal vesicle in prostate glands

• stores mature sperm

• propel sperm into the urethra

XY parasympathetic nervous system

erection

XY sympathetic nervous system

Ejaculation

vagina

musciular canal lined with mucous membrane that extends from the vaginal orifice to cervix

uterus

female smooth muscle organ

parts of the uterus

fundus- superior portion of the uterus

cervix - external entrance from the vagina

middle layer- myometrium (muscle layer)

inner layer- endometrium (glandular layer )