Brainscape's Knowledge GenomeTM

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


See full index

Human physiology Spain > Chapter 9 > Flashcards

Chapter 9 Flashcards

1
Q

6 basic processes in the digestive system

  • Inges(on: taking food into mouth.
  • Diges(on: mechanical and chemical breakdown of food.
  • Secre(on: release of water, acid, buffers, and enzymes into lumen of GI tract.
  • Diges(on: mechanical and chemical breakdown of food.
  • Mixing and propulsion: churning and movement of food through GI tract.
  • Absorp(on: passage of digested products from GI tract into blood and lymph.
  • Defeca(on: elimina>on of feces from GI tract.

put in right order

A
  1. Inges(on: taking food into mouth.
  2. Secre(on: release of water, acid, buffers, and enzymes into lumen of GI tract.
  3. Mixing and propulsion: churning and movement of food through GI tract.
  4. Diges(on: mechanical and chemical breakdown of food.
  5. Absorp(on: passage of digested products from GI tract into blood and lymph.
  6. Defeca(on: elimina>on of feces from GI tract.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The accessory digestive organs include:
* teeth: physical breakdown of food.
* tongue and salivary glands: assists
in chewing and swallowing.
* liver, gallbladder and X:
produce or store secretions that
flow into the GI tract for chemical
breakdown of food.

A

pancreas

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

The wall of the GI tract from the lower esophagus to the anal canal has the same basic,
four-layered arrangement of tissues, from deep to superficial:

  • Muscularis
  • Submucosa
  • Serosa or adventitia
  • Mucosa

put in right order

A
  1. Mucosa
  2. Submucosa
  3. Muscularis
  4. Serosa or adventitia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

. Mucosa is composed of:
1. A layer of epithelium (with …. cells: secrete mucus and fluid and …. cells: secrete hormones)

  1. A layer of X tissue (lamina propria) containing: blood vessels, lymphatic vessels and mucosa-associated lymphatic tissue (MALT, prominent lymphatic nodules contain immune system cells that protect against disease).
  2. A thin layer of X muscle (muscularis mucosae): its movements ensure
    that all absorptive cells are fully exposed to the contents of the GI tract.
A

exocrine: mucus etc
Endocrine: hormones
connective
smooth

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

Submucosa consists of areolar X tissue that binds the mucosa to the muscularis. It
contains:

  • Blood and lymphatic vessels that receive absorbed food molecules.
  • An extensive network of neurons: submucosal X.
  • Glands and lymphatic 7ssue
A

connective
plexus

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

Muscularis:

  • Skeletal muscle in the mouth, pharynx, and superior and middle parts of the esophagus
    for voluntary swallowing, and in the external anal sphincter for voluntary control of
    defecation.
  • Smooth muscle throughout the rest of the tract: inner sheet of circular fibers and an
    outer sheet of longitudinal fibers. Its involuntary contractions help break down food, mix
    it with digestive secretions, and propel it along the tract.

Between the layers of the
muscularis is a second X of neurons: the myenteric X.

A

plexus

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

Serosa or adventitial:

  • Serosa or visceral peritoneum: superficial serous membrane composed of X
    tissue and epithelium only present in portions of the GI tract that are suspended in the
    abdominal cavity.
  • Adventitia: superficial layer of connective tissue in X
A

connective
esophagus.

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

The ENS contains sensory neurons,
interneurons, and motor neurons:
what do they do?

A

sensory: chemical changes/stretching
interneurons: sensory info -> motor neurons
motor neurons: contraction and secretion of glands

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

Which of these plexuses controls secretions and which controls GI tract motility?

  • submucosal
  • myenteric
A

submucosal: secretions
myenteric: motility

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

Afferent pathway (enteric sensory neurons): ENS contains two major types of sensory
receptors:
1. Xreceptors: respond to certain chemicals in the lumen
2. Xreceptors: respond to stretch

A

Chemo
Mechano

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q
  • Sensory fibers send information to the X but also to the prevertebral
    ganglia of the spinal cord, to the spinal cord and to the brainstem
A

enteric plexuses

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

A/Efferent pathway (enteric motor neurons): govern contrac>on of gastrointes>nal tract
smooth muscle and secre>on of gastrointes>nal tract glands

A

Efferent

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

Although the neurons of the ENS can func>on independently, they are subject to
regula(on by the neurons of the autonomic/somatic nervous system:
1. Sympathetc division: in/decreases actvity of ENS
2. Parasympathetic division: in/decreases activity of ENS

A

automatic,

decreases
increases

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

The oral vestibule is the space bounded externally by the X and lips and
internally by the gums and teeth.

  • The uvula is a fingerlike muscular structure hanging from the free border of the soft
    palate which prevents swallowed food from entering the nasal cavity.
A

cheeks

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

The three major salivary glands are: parotid, sublingual, and submandibular. They secrete mucus which contains which digestive enzyme?

A

amylase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q
  • Functions saliva:
    1. Lubricates
    2. Dissolves foods
    3. Begins the chemical breakdown
    of carbohydrates (stach) and
    lipids
    4. Protection: IgA prevents
    a[achment of microbes so they
    cannot penetrate the
    epithelium, and lysozyme kills
    bacteria
A

ok

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

Chemical digestion in the mouth by two enzymes:

  1. Salivary amylase:
    * Secreted by the salivary glands
    * Initiates the breakdown of starch
  2. X:
    * Secreted by lingual glands in the tongue
    * Becomes activated in the acidic environment of the stomach and thus starts to work after food is swallowed
    * Breaks down dietary triglycerides (fats and oils) into fatty acids and
    diglycerides
A

Lingual lipase

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

Pharynx or throat is a funnel-shaped tube that extends from the internal
nares to the esophagus posteriorly and to the larynx anteriorly.

It is divided into three parts:
1. the Xpharynx
2. the oropharynx
3. laryngopharynx or hypopharynx.

A

naso

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

At each end of the esophagus, the muscularis becomes
slightly more prominent and forms two sphincters:

  1. X sphincter: skeletal muscle,
    regulates the movement of food from the pharynx
    into the esophagus
  2. X (cardiac) sphincter: smooth
    muscle, regulates the movement of food from the
    esophagus into the stomach
A

Upper esophageal
Lower esophageal

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

Deglutition or X is the movement of food from the mouth into the
stomach.
* It involves the mouth, pharynx, and esophagus and is facilitated by the secretion
of saliva and mucus.

A

swallowing

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

Swallowing occurs in three stages:

(1) X stage: the bolus is passed into the oropharynx.

(2) X stage: the involuntary passage of the bolus through the pharynx into
the esophagus: the tongue rises against the palate, the nasopharynx is closed off,
the larynx rises, the epiglo`s seals off the larynx, and the bolus is passed into
the esophagus.
Deglution
(3) Esophageal stage: the
involuntary passage of the
bolus through the
esophagus into the
stomach. Food moves
through the esophagus into
the stomach via peristalsis

A

Voluntary
Pharyngeal

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

Four parts of the stomach: put in right order from esophagus to duodenum

Fundus
Body
Cardia
Pyloric part

A
  1. Cardia: surrounds the
    opening of the esophagus
    into the stomach.
  2. Fundus: rounded por>on
    superior to and to the leb of
    the cardia.
  3. Body: large central por>on of
    the stomach.
  4. Pyloric part. Pylorus connects
    to the duodenum.
23
Q

stomach functions:

  1. Mixes saliva, food, and gastric juice to form X. X: is a soupy liquid result of
    movements of the gastric contents mixed with gastric juice.
  2. Serves as reservoir for food before release into small intes>ne.
  3. Secretes gastric juice, which
    contains:
    * HCl: kills bacteria and
    denatures proteins.
    * Pepsin: begins the digestion
    of proteins.
    * Intrinsic factor: aids
    absorption of vitamin B12.
    * Gastric lipase: aids
    digestion of triglycerides.
  4. Secretes gastrin into blood.
A

chyme

24
Q

Secretions from several gastric
glands flow into each X (narrow channels)
and then into the lumen of the
stomach.

A

gastric pit

25
Q

Three types of endo/exocrine gland cells that secrete their products into the
stomach lumen. The secretion of these cells= gastic juice

A

exo

26
Q

Gastric juice consists of:

  1. Mucous neck cells: secrete mucus
    (there are also surface mucous cells)
  2. Chief (zymogenic) cells: secrete
    pepsinogen and gastric lipase.
  3. X cells: produce intrinsic factor
    (needed for absorption of vitamin
    B12) and hydrochloric acid (HCl)
A

Parietal

27
Q

One type of enteroendocrine cell: G
cell: located mainly in the pyloric
antrum, secretes the hormone X
into the bloodstream

A

gastrin

28
Q

Each peristaltic wave moves gastric contents from the body of the stomach down into
the antrum: X
* The pyloric sphincter normally remains almost, but not completely, closed.
* Because most food particles in the stomach initially are too large to fit through the
narrow pyloric sphincter, they are forced back into the body of the stomach:
retropulsion.

A

propulsion.

29
Q

Once the food par>cles in chyme are small enough, they can pass through the pyloric
sphincter: gastric X.
* Gastric emptying is a slow/fast process

A

emptying

slow: only about 3 mL of chyme moves through the
pyloric sphincter at a time

30
Q

Chemical digestion in the small intestine depends on the activities of the X,
X, and X.

A

pancreas
liver
gallbladder

31
Q

The pancreas consists of a head, a body, and a tail and is usually connected to the
duodenum of the small intestine by two ducts

true/false

A

true

32
Q

Pancreatic juices are secreted by endo/exocrine cells into small ducts that ultimately unite to
form two larger ducts, the X duct (or duct of Wirsung) and the accessory duct.
These in turn convey the secretions into the small intestine.

A

exo
pancreatic

33
Q

The X duct joins the common X duct from the liver and gallbladder and
enters the duodenum as a dilated common duct called the hepatopancreatic ampulla
(or ampulla of Vater).

A

pancreatic
bile

34
Q

The pancreas is made up of small groups of glandular epithelial cells called acini:
* 99% of the acini constitute the endo/exocrine portion of the organ and secrete
pancreatic juice.

  • 1% of the acini are the pancreatic (or Langerhans) islets, they form the endo/exocrine
    portion of the pancreas and secrete the hormones glucagon, X,
    somatostatin and pancreatic polypeptide.
A

insulin

35
Q

The pancreas produces pancreatic juice, a clear, colorless liquid consisting
mostly of water, some salts, sodium bicarbonate, and several enzymes.

  • The sodium bicarbonate gives pancreatic juice a slightly X pH that buffers acidic gastric juice in chyme, stops the acton of X from the
    stomach, and creates the proper pH for the action of digestive enzymes in the
    small intestine
A

alkaline (7.1–8.2)
pepsin

36
Q

The enzymes in pancreatic juice include:
* Pancreatic amylase: X-digesting enzyme
* Trypsin, chymotrypsin, carboxypeptidase, and elastase: enzymes that
digest proteins into peptides. These enzymes are produced inactive
to not digest cells of the pancreas itself.
* Pancrease lipase: principal triglyceride–diges>ng enzyme in adults
* Ribonuclase and deoxyribonuclease: enzymes that digest ribonucleic acid
(RNA) and deoxyribonucleic acid (DNA) into nucleotides.
* Trypsin inhibitor.

A

starch

37
Q

Main function of hepatocytes is to secrete bile, a yellow, brownish, or olive-green
liquid.

what are hepatocytes

A

major functional cells of the liver

38
Q

Bile salts (sodium and potassium) play a role in X: the breakdown of large
lipid globules into a suspension of small lipid globules

Bile salts also aid in the absorption of lipids following their digestion.

A

emulsification

39
Q

In addition to secreting bile, necessary for the absorption of fatty foods, the liver
performs other vital functions:

  1. metabolism of carbohydrates: helps maintain adequate blood glucose levels, among other functions.
  2. lipid metabolism.
  3. protein metabolism: deaminate amino acids, convert ammonium (toxic) into urea, synthesize most plasma proteins: globulins,
    albumin, prothrombin and fibrinogen.
  4. Processes drugs (detoxifying function) and hormones.
  5. Excretes bilirubin.
  6. Storages of substances: glycogen, vitamins (A, B12, D, E and K) and minerals
    (iron and copper).
  7. Phagocytosis: thanks to Kupffer cells.
  8. Activation of vitamin D (along with the skin and kidney).
A

ok

40
Q

Small intestine is divided into pieces, place in order of pyloric sphincter to ileocecal sphincter

  1. Jejenum
  2. Ileum
  3. duodenum
A
  1. Duodenum: the first part of the small intestine, is the shortest region, and is
    retroperitoneal. It starts at the pyloric sphincter of the stomach and is in the form of a
    C-shaped tube that extends about 25 cm until it merges with the jejunum.
  2. Jejunum: is the next portion and is about 1 m long and extends to the ileum.
  3. Ileum: is the final and longest region of the small intestine. It measures about 2 m and
    joins the large intestine at a smooth muscle sphincter: ileocecal sphincter.
41
Q

immune system is important in the small intestine:

  1. Small intestinal mucosa has an abundance of mucosa-associated lymphoid (ssue
    (MALT).
  2. Solitary lymphatic nodules are also found (particularly in the distal part of the
    ileum).
  3. Groups of lymphatic nodules (X), are also present in the ileum
A

Peyer’s patches

42
Q

most of absorption takes place in the ….

A

small intestine

43
Q

epithelial layer of small intestine:

  1. Absorptive cells: contain enzymes (brush-border enzymes) that digest food and possess
    microvilli that absorb nutrients in small intestinal chyme.
  2. Exocrine cells:
    * X cells: secrete mucus.
    * X cells: secrete lysozyme (bactericidal enzyme), and are capable of phagocytosis.

Paneth cells may have a role in regulating the microbial population in the small
intestine.

A

Goblet: mucus
Panet: lysozyme

44
Q

Endocrine cells in small intestine:

  • S cells: secrete the hormone secretin
  • CCK cells: secrete the hormone cholecystokinin (CKK)
  • X cells: secrete the hormone glucose-dependent insulinotropic peptide (GIP)
A

K

45
Q

Small intestinal mucosa contains many deep crevices lined with glandular epithelium.

  • Cells lining the crevices form the intestinal glands, or crypts of Lieberkühn, and secrete
    X
A

intestinal juice.

46
Q

Chyme remains in the
small intestine for x-x
hours.

A

3–5

47
Q

From absorptive epithelial cells, X,
amino acids and SCFA
are transported in the X

A

monosaccharides
blood

48
Q

X and monoglycerides are recombined to form triglycerides, -> become coated with proteins (chylomicrons) -> lymphatic vessels

A

Long-chain fatty acids

49
Q

Digestive activities occur in three overlapping phases:

  1. Cephalic phase: neuronal mechanism
  2. Gastric phase: neural and hormonal mechanisms
  3. Intestinal phase: neural and hormonal mechanisms

explain

A

cephalic: before food is swallowed
gastric: food in the stomach
intestinal: food leaves stomach

50
Q

during cephalic phase,

The brain stem activates:

  • Facial (VII) and glossopharyngeal
    (IX) nerves: stimulate the salivary
    glands to secrete saliva.
  • X nerve: stimulate the
    gastric glands to secrete gastric
    juice.
A

Vagus

51
Q

gastric phase: NEURAL REGULATION: when the food enters
the stomach:

  1. Stomach distends and activated stretch
    receptors in its walls.
  2. X buffer the stomach
    acid, pH de/increases and
    chemoreceptors are activated.
A

Ingested proteins
increases

52
Q
  • From the stretch receptors and
    chemoreceptors, nerve impulses propagate
    to the submucosal plexus, where they
    actvate parasympathetic/sympathetic and enteric
    neurons.
A

parasympathetic

53
Q
A

Human physiology Spain (23 decks)

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