Ch. 16- Biochemistry

Question 1

biochemistry

Answer 1

the study of the chemistry of living things and life processes

Question 2

cell

Answer 2

structural unit of all living things

Question 3

cell membrane

Answer 3

the double layer of lipid molecules enclosing a cell, through which the cell absorbs nutrients and eliminates waste

Question 4

major parts of the cell & their functions

Answer 4

1. nucleus: contains DNA molecules, which control heredity
2. ribosomes: handles protein synthesis
3. mitochondria: produces energy; the cell’s “batteries”
4. (plant cells only) chloroplasts: convert energy from the sun to chemical energy

Question 5

what are the main sources of energy for plant cells & for animal cells?

Answer 5

plant cells = the sun

animal cells = carbohydrates, fats, proteins

Question 6

metabolism

Answer 6

the set of coordinated chemical reactions that keep the cells of an organism alive

Question 7

catabolism

Answer 7

any metabolic process in which complex compounds are broken down into simpler substances

Question 8

anabolism

Answer 8

the building up of molecules through metabolic processes

Question 9

carbohydrate

Answer 9

a compound consisting of carbon, hydrogen, and oxygen, with hydrogen and oxygen in a 2:1 ratio; a starch or sugar

Question 10

monosaccharide

Answer 10

a carbohydrate that cannot be hydrolyzed into simpler sugars

Question 11

aldose

Answer 11

a monosaccharide with an aldehyde functional group (glucose & galactose)

Question 12

ketose

Answer 12

a monosaccharide with a ketone functional group (fructose)

Question 13

disaccharide

Answer 13

a sugar that on hydrolysis yields two monosaccharide molecules per molecule of disaccharide (sucrose & lactose)

Question 14

which monosaccharides are yielded by hydrolyzing sucrose?

Answer 14

glucose & fructose

Question 15

which monosaccharides are yielded by hydrolyzing lactose?

Answer 15

glucose & galactose

Question 16

polysaccharide

Answer 16

a carbohydrate, such as starch or cellulose, that consists of many monosaccharide units linked together

Question 17

alpha linkage (a-linkage)

Answer 17

the way glucose units are linked in starch; results in bent polymers with helix-like chains that form granules

Question 18

beta linkage (b-linkage)

Answer 18

the way glucose units are linked in cellulose; results in long polymers with straight chains that form fibers

Question 19

amylose

Answer 19

a plant starch that consists of glucose units joined in a continuous chain like beads on a string, resulting in long granules

Question 20

amylopectin

Answer 20

a plant starch that consists of branched chains of glucose units; forms a branch about every 25 glucose units, resulting in long granules

Question 21

glycogen

Answer 21

an animal starch that consists of branched chains of glucose units; forms a branch about every 10 glucose units, resulting in small granules/clusters

Question 22

what are the dietary carbohydrates?

Answer 22

1. sugars

2. starches

Question 23

blood sugar

Answer 23

glucose, a simple sugar that is circulated in the bloodstream and used directly by cells for energy

Question 24

how is high-fructose corn syrup (HFCS) made?

Answer 24

by treating corn syrup with enzymes to convert much of the glucose to fructose

Question 25

how is corn syrup made?

Answer 25

by splitting long cornstarch chains

Question 26

starch

Answer 26

a polymer of glucose units joined by alpha linkages; a complex carbohydrate

Question 27

cellulose

Answer 27

a polymer comprised of glucose units joined by beta linkages

Question 28

what does the human body do with glucose?

Answer 28

breaks it down through a complex set of over fifty chemical reactions that result in the production of carbon dioxide, water, and energy

Question 29

what does the human body do with fructose?

Answer 29

stores it in the liver to stimulate the formation of fats

Question 30

what does the human body do with cellulose?

Answer 30

it cannot break down/catabolize it; used as dietary fiber

Question 31

what does the human body do with lactose?

Answer 31

every typical human is born with an enzyme that catabolizes lactose, but as some humans age, they begin lacking that enzyme, resulting in lactose intolerance

Question 32

what does the human body do with starch?

Answer 32

hydrolyzes it to glucose

Question 33

what happens when we eat more carbohydrates than our body can use?

Answer 33

the body stores the excess carbohydrates in the liver & in muscle tissue as glycogen

Question 34

whats the most abundant carbohydrate found in nature?

Answer 34

cellulose

Question 35

name the sugars found in the various foods...

Answer 35

...fruit? - fructose ...honey? - fructose & glucose ...table sugar? - sucrose ...corn syrup? - glucose

Question 36

lipid

Answer 36

a substance from animal or plant cells that is soluble in solvents of low polarity and insoluble in water

Question 37

fat

Answer 37

an ester formed by the reaction of glycerol with 3 fatty-acid units; a triglyceride or triacylglycerol

Question 38

fatty-acid

Answer 38

a carboxylic acid that contains 4 to 20 or more carbon atoms in a chain

Question 39

triglyceride

Answer 39

an ester of glycerol with 3 fatty-acid units; also called a triacylglycerol

Question 40

oil (food)

Answer 40

a substance, formed from glycerol & fatty-acids, which is liquid at room temperature; "liquid fats"

Question 41

saturated fat

Answer 41

a triglyceride composed of a large proportion of saturated fatty acids esterified with glycerol

Question 42

iodine number

Answer 42

the mass in grams of iodine that reacts with 100 grams of a fat or oil; an indication of the degree of unsaturation - high iodine number = high degree of unsaturation - low iodine number = high degree of saturation

Question 43

polyunsaturated fat

Answer 43

a fat containing fatty-acid units that have two or more carbon-carbon double bonds