topic 3: digestive system

Question 1

what is homeostatsis?

Answer 1

ability of an organism or cell to maintain internal equilibrium by adjusting its physological processes

Question 2

What are the 4 major processes of the digestive system?

Answer 2

1. Ingestion
2. Digestion
3. Absorption
4. Egestion

Question 3

what is ingestion?

Answer 3

taking in food
-mouth

Question 4

what is digestion?

Answer 4

breaking down food (mechanical and chemical)
-mouth and stomach intestine

Question 5

What is absorption?

Answer 5

making nutrients in food available to your circulatory system
-small intestine

Question 6

what is egestion?

Answer 6

getting rid of indigestiable food
-large intestine

Question 7

what is the order of digestion in body parts?

Answer 7

1. mouth
2. pharynx
3. esophagus
4. stomach
5. small intestine
6. large intestine
7. anus

Question 8

what do teeth aid in?

Answer 8

mechanical digestion by chewing food into smaller pieces

Question 9

what is mastication?

Answer 9

chewing

Question 10

what does chewing help with?

Answer 10

easier swallowing and faster chemical breakdown in digestive tract

Question 11

what do canines do?

Answer 11

rip

Question 12

what do incesors do?

Answer 12

shred

Question 13

what do molars do?

Answer 13

grind

Question 14

what does saliva contain?

Answer 14

the enzyme amylase, which chemically breaks down starches

Question 15

what does saliva do to food?

Answer 15

softens it

Question 16

what tates are taste buds sensitive to?

Answer 16

sweet, salty, sour and bitter

Question 17

what happens when you first eat food?

Answer 17

it is rolled into a small ball called a bolus which is passed to the back of the throat and swallowed.

Question 18

what does the epiglottus do when swallowing?

Answer 18

closes the turchea

Question 19

ingestion starts both what two types of digestions?

Answer 19

chemical and mechanical

Question 20

what is the pharynx?

Answer 20

the “crossroad” between mouth, nose, trachea and esophagus

Question 21

what is the esophagus?

Answer 21

25cm long muscular tube that functions to transport food and liquids from the pharynx to the stomach by waves of muscular contractions (peristalsis)

Question 22

is perstalsis involuntary?

Answer 22

yes

Question 23

Where does food enter the stomach?

Answer 23

Though the cardiac lower esophageal sphincter

Question 24

What part of the stomach creates inactive enzymes?

Answer 24

The upper portion (fundus)

Question 25

Where do enzymes become active?

Answer 25

In the lower portion of the stomach (pycloric) as they begin to take part in chemical digestion

Question 26

Where does food leave the small intestine through?

Answer 26

Pyloric sphincter

Question 27

How much food can the stomach hold?

Answer 27

2-4L

Question 28

How many layers and there names within the stomach?

Answer 28

3 layers, longitudinal, circular and oblique (diagonal) rows

Question 29

What do the 3 muscles help with?

Answer 29

Squeeze and churn the food (mechanical)

Question 30

Where are gastric glands located

Answer 30

In the wall of the stomach

Question 31

What do gastric glands produce?

Answer 31

Hydrochloric acid and pepsinogen

Question 32

What is pepsinogen?

Answer 32

An inactive form of an enzyme called a precursor

Question 33

What does HCL do in the stomach?

Answer 33

Kills bacteria, breaks down food and provides the right pH for enzymes to work

Question 34

What do mucous cells do?

Answer 34

Secrete protective coating against HCL

Question 35

What happens to pepsinogen in the presence of HCL?

Answer 35

Converted to an active form of pepsin
-pepsin acts on proteins and breaks them down into smaller pieces

Question 36

What does lipase do in the stomach ?

Answer 36

Starts the breakdown of lipids

Question 37

What is the soupy mixture of food and digestive juices called after 3-5 hours ?

Answer 37

Chyme

Question 38

What does chyme do?

Answer 38

Stimulated the pycloric valve to open and food moves into small intestine