lec 8 pt2 nutrition and digestion

Question 1

stuff to review NOT A FLASHCARD

Answer 1

-digestion overview diagram
-enzyme breakdown diagram
-tutorials at end of slides

Question 2

need to know?? NOT A FLASHCARD

Answer 2

-hormones that regulate digestion?
-animal digestive systems?

Question 3

living organisms require ____ as nutrients

Answer 3

elements

Question 4

what are macronutrients?

Answer 4

elements needed in large amounts

Question 5

which 3 macronutrients make up 93% of our weight?

Answer 5

C, H, O

Question 6

what are micronutrients? whats an example?

Answer 6

tiny amts necessary for life
eg. vitamins

Question 7

which element is needed in a small amount to be used to make hormones?

Answer 7

iodine

Question 8

what are 3 main categories of human dietary requirements?

Answer 8

-carbohydrates
-fats (lipids)
-protien

Question 9

explain why we need each of the 3 categories of human dietary requirements?

Answer 9

carbs:
-source of energy+carbon

fats:
-concentrated form of energy
-essential fats: required to make certain compounds

protein:
-source of amino acids
-b/c we cant make all AA

Question 10

what are essential amino acids?

Answer 10

amino acids we MUST obtain from food`

Question 11

how to animals obtain nutrients?

Answer 11

digesting food in order to absorb necessary molecules

Question 12

one way system that carries food from mouth to anus

Answer 12

digestive system (gut)

Question 13

what are two roles of saliva?

Answer 13

-moistens food to aid in digestion
-breaks starch–> sugar w/ enzyme amylase

Question 14

what is the route food takes after leaving the mouth?

Answer 14

esophagus–> stomach–>small intestine–>colon–> anus

Question 15

once food reaches the stomach, what does the stomach do?

Answer 15

mixes food with acid + stores it

Question 16

where does food go after the stomach? what happens here?

Answer 16

small intestine

breaks down macromolecules for easy absorption

-small intestine’s epithelial cells absorb

Question 17

removes additional water and nutrients from food

Answer 17

colon/large intestine

Question 18

what happens after food passes through the colon?

Answer 18

food becomes feces

expelled thru anus

Question 19

the animal digestive system involves ______, ________ and waste.

Answer 19

breakdown, absorption

Question 20

specialized epithelial cells in the stomach secrete…?

Answer 20

HCl- hydrochloric acid

Question 21

what is the role of hydrochloric acid in the stomach?

Answer 21

-kills most microbes present in food
-breaks down extra-cellular matrix of food

Question 22

what is the purpose of mucous in the stomach? where is it produced?

Answer 22

-protects epithelial cells from HCl (acid)
-secreted from epithelial cells

Question 23

the stomach grinds food by….?

Answer 23

peristalsis: muscle contraction

Question 24

what is peristalsis?

Answer 24

muscle-driven movement of the gut

Question 25

what are proteases in the stomach? what is an important protease? where are they produced?

Answer 25

enzymes secreted by epithelial cells

Pepsin: breaks down protein

Question 26

what is the role of epithelial cells in the small intestine?

Answer 26

-secrete digestive enzymes
-absorb nutrients thru active transport

Question 27

what is the pancreas?

Answer 27

source of digestive enzymes

Question 28

what are 3 important digestive enzymes from the pancreas? what do they do?

Answer 28

lipase- breaks down fats

protease- breaks down protiens

amylase- breaks down carbs

Question 29

what is bile? where is it produced? where is it stored?

Answer 29

liquid that emulsifies lipids, increases efficiency of lipase

produced in liver
stored in gallbladder

Question 30

explain how the anatomy of the small intestine makes it the ultimate absorber

Answer 30

cavity lined with villi (finger-like projections of epithelial cells)

villi increase # of epithelial cells, therefore increasing absorption

villi kinda look like a microfiber duster

Question 31

why must food be broken down by enzymes during the digestion process?

Answer 31

in order to enter epithelial cells

Question 32

what occurs in the colon(large intestine) when it receives digested food?

Answer 32

-mostly water and some nutrients are absorbed
-food becomes feces

Question 33

the bacteria that heavily colonize the colon are called? what are two functions of this bacteria?

Answer 33

the normal flora

-produces certain vitamins (K)
-repels+inhibits pathogenic (harmful) bacteria

Question 34

the human digestive system is regulated by…?

Answer 34

hormones

Question 35

what is a common example of missing enzymes we see?

Answer 35

lack of lactase

causes lactosis/ lactose intolerance

Question 36

what is one enzyme that all animals are missing? what does it cause?

Answer 36

lack cellulase

cant digest cellulose so we don’t get much energy from plants

Question 37

how are herbivores able to survive off of plants if they lack cellulase?

Answer 37

intestinal microorganisms (bacteria, fungi, protists)
digest cellulose, release glucose