anatomy exam #3

look at large intestine diagram

what are the functions of the large intestine?

1) propulsion using haustral contractions

2) most of H2O absorption

3) eliminates feces

4) synthesizes/absorbs vitamin K and B

What happens if food spends too long or too short in large intestine?

too long → constipation → need meds if bad enough

too short → diarrhea (not enough water is getting absorbed) → if a lot over time can lead to death

What is the gut microbiome?

mostly in LI but some in SI, made of more bacteria than human cells, controls everything (nervous, endocrine, and immune system), functions change by if healthy or not, antibiotics might throw it off, yogurt/supplements can help reset

What are the hormones released in the large intestine? What’s their function? Where are they produced? Where do they act on? What affects production?

1) gherlin- produced in stomach, acts on hypothalamus, increases appetite/growth hormone, promotes fat storage, increases when fasting, if appetite/production is disconnected → overeating, decrease sleep → increases gherlin → eating more → weight gain

2) leptin → produced by adipose cells, decreases hunger/food intake, increases energy use, acts on hypothalamus, makes you feel satiated

Where are carbohydrates digested? What digests them (enzyme)? What are they digested into?

starch and disaccharides → oligosaccharides and disaccharides using salivary amylase and pancreatic amylase → monomers using brush border enzymes so they can be absorbed

occurs in mouth and small intestine

Where are proteins digested? What types of enzymes digest them? What are they digested into?

proteins → large polypeptides using pepsin from stomach glands in presence of HCl → small polypeptides/peptides using pancreatic enzymes (trypsin, chymotrypsin, carboxypeptidase) in SI → amino acids, some dipeptides/tripeptides using brush border enzymes in SI

Where are fats digested? What types of enzymes digest them? What are they digested into?

unemulsified triglycerides → monoglycerides and fatty acids using lingual lipase (small effect) in mouth, gastric lipase (small effect) in stomach, emulsify using detergent action of bile salts from liver into SI, and pancreatic lipase in SI

What are the functions of the urinary system?

1) produces urine

2) controls H₂O and ion (Ca⁺⁺, K⁺, Na⁺, Cl⁺) balance

3) acid base balance- H⁺

4) gets ride of metabolic wastes/nitrogenous compounds that are products of cellular respiration from breakdown of proteins when N is released from AA

renal cortex vs medulla

cortex- superficial

medulla- deep

what is the job of the nephron? where is it?

functional unit of kidney which urine is produced, spans cortex and medulla

What are the two types of nephrons? how do they differ from each other?

1) cortical nephrons- shorter LOH, >80% of blood, glomerulus is farther from cortex-medulla junction, no capillaries of LOH but on PCT and DCT

2) juxtamedullary nephrons- longer LOH, <20%, closer to junction, LOH is surrounded by vasa recta

how is a longer LOH more advantageous?

creates more of a concentration gradient in medulla because as go farther down it gets saltier and saltier

what artery and vein separates the cortex and medulla

arcuate artery/vein

how is passive transport seen in a nephron

with high pressure in afferent arteriole so filtration is passive because pressure gradient

What are the three main processes in the nephron? Where is the movement happening?

1) filtration- from blood capillaries → tubules in glomerulus

2) reabsorption- from tubules → blood

3) secretion- from blood → tubules everywhere in system basically

what is the function of the glomerular capsule

catches material to get rid of