Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy Exam III > Digestive 2 > Flashcards

Digestive 2 Flashcards

1
Q

What is the stomach and its function?

A

A j-shaped sac. It is a temporary storage tank (2-6 hours) and site of demolition

It starts chemical digestion- the breakdown of proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is chyme?

A

a juice, liquified slurry of food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Rugae

A

mucosal folds seen in an empty stomach

only seen in empty stomach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How are the tunics modified in the stomach?

A

Muscularis has an added internal, oblique layer to allow increased mixing and churning.

Mucosa has a simple columnar epithelium made entirely of mucous cells. HCI is secreted into our stomach so we need an extra layer to protect us. - produces a cloudy, double layer of alkaline mucus. It is dotted with millions of deep gastric pits -pits in stomach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do gastric glands do?

A

responsible for producing gastric juice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What type of cells are in the gastric glands?

A

Mucus Neck Cells
Parietal Cells
Chief cells
Enteroendocrine cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Mucus neck cells

A

produce thin, soluble mucus

-sit at neck

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Parietal cells

A

produce HCI with a pH of 1.5-3.5, required to activate pepsin. they also secrete intrinsic factor (required to absorb b12)

B12 is used for forming RBC. If we can’t form B12, we won’t make RBC and will die from anemia.

Pepsin breaks down proteins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Chief cells

A

secrete pepsinogen (inactive pepsin) and lipsases (enzymes that break down fats)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Enteroendocrine Cells

A

Secrete chemical messengers into the lamina propia as well as gastrin (hormone that helps secrete gastric juices)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Can you live without a stomach

A

Yea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Mucosal barrier

A

gastric juice can digest the stomach so we create a mucosal barrier. It includes a thick coating of bicarbonate-rich mucus, tight junctions between epithelial cells(prevent leaking juice), and quick replacement of damaged mucosal cells by stem cells.

Stem cells rapidly divide and renew stomach lining.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Gastritis

A

inflammation of stomach in response to breaches of mucosal barrier, starts digesting a little bit of itself

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Peptic/gastric ulcers

A

erosions of the stomach wall- cause gnawing epigastric pain

pain worse 1-3 hours after eating and resolved when eating. Why? ulcers are most irritated bc we secrete acid and breach the wall so the acid is painful. When we eat again, we put basic chyme into the stomach that becomes acidic, so we coat the ulcer and make them temporarily comfortable.

Ulcers predominantly blamed on inseds like ibuprofen. Ulcers are linked to peritonitis and H.Pylori- a type of acid resistant to bacteria. They can chew through the mucosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Digestive processes in the STOMACH

A

propulsion; peristalsis (rhytmic waves of smooth muscle pushing food)

mechanical breakdown: mixing and churning

Digestion: breakdown of fats and HCI and pepsin
renin in infants

Absorption: only lipid-soluble substances- alcohol- and aspirin

Secretion of Intrinsic factor: essential for B12 absorption and making functional RBC.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How much gastric juice is secreted a day?

A

3L a day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the neural mechanisms of regulation?

A

stimulation by the vagus nerve (Parasymphathetic)

stimulation by the sympathetic nervous system decreases secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are hormonal mechanisms of regulation?

A

Gastrin stimulates secretion of HCI by the stomach

Gastrin stimulates secretion of gastrin antagonists by the SI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How much HCI our parietal cells make is stimulated by

A

ACh, gastrin (kick up secretions), and histamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 3 phases of gastric secretions?

A

Cephalic/relax phase
Gastric phase
Intestinal phase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Cephalic/relax phase

A

-happens in head

triggered by smelling food, tasting food, or seeing food. It acts via the vagus nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Gastric Phase

A

triggered by stretch receptors and/or chemical stimuli-partially digested by caffeine, protein, rising pH.

Activates G cells (enteroendocrine cells) to secrete gastrin
Gastin releases HCI
Low pH between meals or firing of the SNS will inhibit gastrin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Gastric phase

A

partially digested food enters the SI and triggers the release of intestinal gastrin

Distention of the SI/presence of acidic, fatty, or hypertonic chyme will inhibit gastric secretions- protects SI from excess acidity and being overwhelmed.

Enterogastric reflex: short reflexes by the ENS and long reflexes by the sympathetic and vagus nerves inhibit acid secretions

Enterogastrones: duodenal enteroendocrine cells release secretin or CCK to inhibit gastric secretions (slow down once food comes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How does the regulation of the gastric emptying work?

A

typically empties in 4 hours

The duodenum prevents overfilling by controlling how much chyme enters- stretch and chemical receptors trigger the enterogastric reflex and enterogastrones to inhibit gastric secretions and to reduce the force of pyloric contractions.

Carbohydrate rich foods move quickly through the duodenum, but fat form an oily layer on top of chyme and are digested more slowly. Fatty chyme delays stomach emptying (may remain for 6 hours)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Vomiting/emesis

A

extreme stretching of the stomach

intestinal irritants such as bacterial toxins, excessive alcohol, spicy foods, certain drugs.

26
Q

What do bloodbourne molecules and sensory impulses stimulate?

A

the emetic center of the medulla

27
Q

What are the mechanics of vomiting/emesis?

A

diaphragm and abdominal wall muscles contract, abdominal pressure rises, gastroesophageal spinchtor relaxes, and soft palate elevates to close off nasal passages.

Excessive vomiting can lead to dehydration, electrolyte imbalance, and acid-base imbalance.

28
Q

What is the function of the liver

A

produce bile

29
Q

What is bile?

A

a fat emulsifier that processes blood bourne nutrients, stores fat-soluble vitamins, and performs detoxification

made in the liver and stored in the gallbladder

30
Q

What is the chief function of the gallbladder?

A

storing bile

31
Q

What is the function of the pancreas?

A

supplies most of the enzymes needed to digest chyme as well as bicarbonate needed to neutralize stomach acid

32
Q

What is the bodies largest gland?

A

the liver

33
Q

What are the lobes of the liver?

A

right, left, caudate, and quadrate

34
Q

What is the Falciform ligament?

A

separates the larger right lobe from the smaller left lobe and suspends the liver from the diaphrahm and anterior abdominal wall.

it becomes the round ligament/ligamentum teres

35
Q

What is the round ligament/ ligamentum teres?

A

remnant of fetal umbilical vein; runs along the free edge of the falciform ligament

36
Q

What is the pathway for bile?

A

Bile leaves the liver by the R and L hepatic ducts.

These ducts fuse together to form the common hepatic duct.

The common hepatic duct fuses with the cystic duct from the gallbladder.

37
Q

What is the common bile duct?

A

the combination of the cystic duct and the common hepatic duct

38
Q

What are liver lobules?

A

hexagonal, structural and functional units

composed of plates of hepatocytes (liver cells) that process and filter nutrient rich blood (hepatic portal circulation)

39
Q

What does the portal triad of the liver have?

A

Hepatic artery: supplies oxygen to the liver

Hepatic portal vein: brings nutrient-rich blood to intestines

Bile duct: receives bile from bile canalliculi

40
Q

What are liver sinusoids?

A

leaky capillaries located between hepatic plates

blood moves from the hepatic portal vein and the hepatic artery through the sinusoids to the central vein -> IVC

41
Q

What are stellate/hepatic macrophages?

A

exist in liver sinusoids to remove old debris and RBC

42
Q

What is bile and its components?

A

It is a yellow-green alkaline solution. It contains cholestrol, triglycerides, phospholipids, electrolytes, and bile salts.

Bile salts emulsify fats. They are cholestrol derivatives that function in fat emulsification.

Bilirubin: yellow pigment formed from heme during breakdown of RBC. it is metabolized in the SI to stercobilin which gives feces a brown color.

43
Q

What circulation happens in bile?

A

enterohepatic circulation- recycling mechanism that conserves bile salts- salts are reabsorbed in the ileum and returned to the liver by the hepatic portal blood. 95% bile is recycled, 5% newly made

44
Q

Hepatitis

A

inflammation of the liver

Typically, a viral infection, but can be caused by alcohol, drug toxicity, or wild mushrooms.

6viruses: A-F; 2 transmitted through food, remainder by blood

45
Q

Cirrhosis

A

progressive, chronic inflammation from hepatitis or alcoholism. Liver activity is depressed. Liver gets fatty and fibrous. Portal hypertension: flow of blood through liver is abstructed

Hep. C is most closely linked to cirrhosis

46
Q

What is the gallbladder and its function?

A

a thin walled muscular sac on the interior surface of the liver that looks green when filled with bile.

Function: store and concentrate bile. it contains many honeycomb folds that allow for expansion.

47
Q

How do muscular contractions release bile?

A

the cystic duct, which flows into the common bile duct

48
Q

What causes gallstones (biliary calculi)?

A

excess cholestrol or too little bile salts

49
Q

What are gallstones?

A

when cholestrol crystalizes into stones. Gallstones can obstruct the flow of bile from the gallbladder.

50
Q

cholethiasis

A

obstructed flow of bile from the gallbladder

51
Q

obstructed jaundice

A

blockage of bile salts and pigments to build up in blood results in jaundiced or yellow skin

52
Q

How do you treat gallstones?

A

crystal-dissolving drugs, ultrasound vibrations, (lithotripsy), laser vaporization, or surgery.

53
Q

What is the exocrine function of the pancreas?

A

production of pancreatic juice- it has enzymes that breaks up all foodstuff. Multiple ducts secreete into the duodenum by the main pancreatic duct.

54
Q

What is the endocrine function of the pancreas?

A

secretion of insulin and glucagon by pancreatic islet cells.

55
Q

How much pancreatic juice do we make in a day?

A

1200-1500mL

56
Q

What is the composition of pancreatic juice?

A

it is a watery, alkaline solution (pH 8) used to neutralize acidic chyme from the stomach. It also has electrolytes, primarily HCO3-

57
Q

What digestive enzymes are in pancreatic juice?

A

Proteases: for proteins
Amylase; carbohydrates
Lipase: lipids
Nucleases: for nucleic acids

58
Q

What is the hepatopancreatic ampulla?

A

Bile and pancreatic ducts unite in the wall of the duodenum

59
Q

How does the ampulla open into the duodenum?

A

by the major duodenal papilla

60
Q

What is the hepatopancreatic sphinctor?

A

controls entry of bile and pancreatic juice into the duodenum

61
Q

What does the accessory pancreatic duct do?

A

smaller duct that empties directly into the duodenum

Anatomy Exam III (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions