Midterm 1 Section 2

Question 1

arteries vs. veins

Answer 1

arteries - thick walled, wide lumen, dynamic size, smooth inner epithelium
- bright red, oxygenated blood coming from the heart
veins - thinner walled, smooth inner epithelium, withstand less pressure
- more superficially located than the arteries
- lower pressure, dark purple blood

Question 2

hepatic artery and vein, and hepatic portal vein

Answer 2

oxygen rich blood via the hepatic artery, and leaves he liver through the hepatic vein
Most absorbed nutrients/toxins are redirected to liver first through hepatic portal vein

Question 3

circulatory system starting from the right side of the heart

Answer 3

• deoxygenated blood enters the right atrium from the vena cavae
• right atrium to right ventricle, then it is pumped through the pulmonary artery to the lungs where blood is oxygenated
• from lungs to left atrium via the pulmonary vein, into the left ventricle and pumped into the aorta
• from aorta to the body, digestive system and hepatic artery
• fats are absorbed into the lymphatic system
• deoxygenated blood returns from capillaries to the veins
• at the subclavian vein lymph enters the blood stream
• deoxygenated blood returns to the vena cavae and back to the right side of the heart

Question 4

about the lymphatic system

Answer 4

has no pump, circulates one way (relies on movement of body)
circulates between cells and collects into tiny vessels
contains chylomicron lipoproteins to transport fat and fat-soluble vitamins

Question 5

angina vs. myocardial infarction

Answer 5

angina - chest pain from heart working harder due to blockage
myocardial infarction - full blockage causing loss of blood flow and death of the artery

Question 6

cardiac output and peripheral resistance definitions

Answer 6

volume of blood pumped out within a time period
resistance to pumped blood by arterioles (constricting and dialating)

Question 7

what is metabolic syndrome?

Answer 7

collection of at least 3: abdominal obesity, triglycerides >150 mg/dL, HDL <40 mg/dL (men) or <50 mg/dL (women), blood pressure > 130/85 mm Hg, fasting glucose > 100 mg/dL

Question 8

pharynx position

Answer 8

at the back of the mouth, connecting point of the respiratory system and GI
the epiglottis covers the trachea below

Question 9

types of amylase

Answer 9

salivary amylase - in saliva to begin to digest complex carbs

Question 10

small intestine sections

Answer 10

duodenum - bile and pancreatic juice excreted
jejunum
ileum - high surface area for absorption

Question 11

large intestine sections

Answer 11

ascending (right side), transverse, descending (left side), sigmoid

Question 12

how the diaphragm moves

Answer 12

with inhale intercostals raise, diaphragm contracts and moves downward to decrease air pressure in lungs
with exhale, intercostals lower, diaphragm relaxes and moves upward to decrease air pressure and force air out of lungs

Question 13

stomach description

Answer 13

3 layers of muscle, mucous lined epithelium
liquifies food content into chyme
release of HCl, intrinsic factor

Question 14

sphincters around the stomach and intestines

Answer 14

cardiac sphincter - between esophagus and stomach
pyloric sphincter - between stomach and duodenum
ileocecal valve - between small intestine and colon
anus - only active control sphincter

Question 15

gastrin hormone job

Answer 15

signals HCl release into stomach until pH 1.5 (negative feedback)
activates pepsinogen into pepsin
increases peristalsis

Question 16

pH range extremes for blood

Answer 16

6.8-8 pH

Question 17

mesentery and peritoneum

Answer 17

connective tissue that holds organs in place in the abdominal cavity and provides bloodflow inside the peritoneal cavity
peritoneum - tissues that line and pad the abdominal cavity and organs

Question 18

retroperitoneal organs

Answer 18

behind the peritoneum - pancreas, duodenum, and rectum

Question 19

greater and lesser omentum

Answer 19

part of the peritoneum that hangs down from the stomach (greater), and liver (lesser)

Question 20

intestinal folds in order of decreasing size

Answer 20

plicae, villi (lacteal vessel and capillaries inside) microvilli (brush border)

Question 21

Gastrin pathway

Answer 21

Responds to: food in the stomach
Secreted from: cells lining the stomach
Stimulates: HCl release
Response: pepsinogen activated into pepsin

Question 22

Secretin pathway

Answer 22

Responds to: fatty chyme in the SI
Secreted from: duodenal wall
Stimulates: pancreatin release and bile production
Response: Release of pancreatic juice/enzymes into duodenum

Question 23

Parietal cells release

Answer 23

in stomach, release HCl and intrinsic factor

Question 24

Cholecystokinin pathway

Answer 24

Responds to: fatty chyme in the SI
Secreted from: intestine wall
Stimulates: gallbladder contractions
Response: more bile released via the common bile duct, slows GI tract motility

Question 25

primary functions of the liver

Answer 25

bile production and excretion first pass metabolism, nutrients from hepatic portal vein metabolism of macronutrients storage of glycogen and of some minerals and vitamins synthesis of albumin (plasma proteins) and clotting factors metabolite detox and purification (activating or inactivating drugs)

Question 26

Pancreatic juice functions and contains

Answer 26

slightly alkaline, bicarb buffers acidic gastric juice in chyme, inactivates pepsin and creates optimal pH (7.1-8.2) for digestive enzymes pancreatic amylase, proteases, pancreatic lipase, and bicarb (pH 9)

Question 27

endocrine vs. exocrine pancreatic examples

Answer 27

endocrine - no ducts, released freely into circulation, hormones - insulin, glucagon by Islet cells exocrine - via ducts to external spaces - acinar cells produce digestive enzymes, through pancreatic duct into SI

Question 28

crypts are

Answer 28

glands between intestinal villi on intestinal epithelium where cells are born (migrate up)

Question 29

goblet cells are

Answer 29

specialized epithelial cells in on villi and colon epithelium that secret mucins

Question 30

where are brush border enzymes?

Answer 30

secreted by villi cells, and cover the microvilli for a final push of digestion

Question 31

what is a portal system?

Answer 31

a system of blood vessels that begins and ends in capillaries ex. hepatic portal from GI to liver for metabolism

Question 32

colon functions

Answer 32

reabsorption of water and electrolytes absorption of vitamins and SCFAs made by bacteria compaction and storage of feces

Question 33

what is a segment of the colon called?

Answer 33

a haustra

Question 34

microbiota functions

Answer 34

100 trillion bacteria: ferment fibers, produce SCFAs, vitamin K, biotin, folate and metabolic regulation recycle bile acids role in chronic diseases (autoimmune, obesity and psychological)

Question 35

C difficile is

Answer 35

Clostridium difficile - pathogenic bacteria in large intestine and destroys colon wall, produces destructive diarrhea

Question 36

Percent water reabsorbed and lost in SI and colon

Answer 36

40% water reabsorbed in SI, 11% reabsorbed in colon 1-2% water lost through feces

Question 37

colon anatomy layers

Answer 37

simple columnar epithelium, goblet cells, intestinal crypts, muscularis mucosa, sub mucosa, serosa (peritineal)

Question 38

what happens in ulcerative colitis?

Answer 38

degradation of crypts, turnover of cells doesn't happen and destroys lining of the colon

Question 39

dysphagia vs. choking

Answer 39

dysphagia - chronic condition where epiglottis doesn't function properly, requires texturizing food choking - acute situation where epiglottis doesn't shut off larynx and bolus gets stuck in trachea instead of going down esophagus

Question 40

transit times (24 hours total)

Answer 40

mouth: less than 1 minute stomach: 1-2 hours small intestine: 7-8 hours colon: 12-14 hours

Question 41

Nerve response in stomach

Answer 41

nerve receptors respond to food in stomach stimulate gastric glands to secrete and muscles to contract emptied stomach no longer stimulates these nerves

Question 42

how does pancreas know which enzymes to secrete?

Answer 42

Hormones from GI tract signal to pancreas which enzymes are needed. This is why sudden dietary changes can cause upset