Chapter #5 - Enzymes

Question 1

What are enzymes?

Answer 1

Proteins that act as biological catalysts.

Question 2

What is the definition of a catalyst

Answer 2

A substance that increases the rate of a chemical reaction and is not changed by the reaction.

Question 3

What would happen if enzymes were not present in your body?

Answer 3

Everything would happen too slowly and organisms wouldn’t be able to sustain life.

Question 4

What is the enzyme for starch?

Answer 4

Amylase

Question 5

What is the enzyme for proteins?

Answer 5

Protease

Question 6

What is the enzyme for carbohydrates?

Answer 6

Carboydrases

Question 7

What helps break down lipids

Answer 7

Lipases

Question 8

What helps breaks DNA?

Answer 8

DNAses

Question 9

What helps break down maltose

Answer 9

Maltase

Question 10

Why are some people lactose intolerant?

Answer 10

Because their bodies do not produce lactase so they therefor cannot tolerate drinking milk.

Question 11

What is DNA?

Answer 11

The material that makes up chromosomes.

Question 12

What are chromosomes?

Answer 12

organized chunks of DNA

Question 13

What are genes?

Answer 13

Sequences of DNA on a chromosome which codes for a specific protein.

Question 14

DNA is…..

Answer 14

double stranded

Question 15

DNA carries…

Answer 15

Codes which instruct the cell which proteins to build. It says which amino acids to link together and in what order.

Question 16

What determines the code?

Answer 16

The sequences of bases in the DNA

Question 17

What are nucleotides?

Answer 17

molecules that link together in long chains to make DNA molecule. Each nucleotide contains a base.

Question 18

How many bases are there and what are they each called?

Answer 18

4 bases
A
C
G
T

Question 19

What are bases?

Answer 19

one of the components of DNA; there are four bases, A, G, T, C, and their sequnces determines genetical info and which proteins are made in a cell.

Question 20

What is the structure of a DNA molecule?

Answer 20

DNA molecules are made up of two chains of nucleotides coiled around one another called a double helix. The 2 chains are held together by complementary base pairs.

Question 21

What are the complementary base pairs?

Answer 21

A and T
C and G

Question 22

What is an example of a protease?

Answer 22

Pepsin

Question 23

What is catalase?

Answer 23

An enzyme that works in all cells. it breaks down a harmful chemical called hydrogen peroxide (H2O2) into water+oxyden.

Question 24

What is hydrogen peroxide?

Answer 24

A byproduct of many chemical reactions in cells.

Question 25

Describe a structure of an enzyme?

Answer 25

The active site is where the substrate attaches to the enzyme. The substrate molecule has a complementary shape to the active site of the enzyme. They bind to form a enzyme-substrate complex. The enzyme than changes the substrate into new molecules product.

Question 26

What factors affect enzymes?

Answer 26

temp. and pH. Every enzyme has an optinal temp. and pH, at which they work the fastest.

Question 27

What is the most common optimum pH? and why?

Answer 27

pH 7 (neutral) because that is the pH in our body and cells. some cell's optimum pH is 2 because they are adapted to work in the stomach.

Question 28

At what temperature do most enzymes stop working?

Answer 28

at above 50 degrees celsius most enzymes denature. (Change shape and do not fit a substrate anymore.) And stop working.

Question 29

What is the ideal temp. for enzymes?

Answer 29

For most enzymes is 37 degrees celcius. (the average/ideal body temp.)

Question 30

What is an example of how enzymes denature?

Answer 30

Protease has a optimal pH of 2 because it works in your stomach. However, at pH 2 the enzyme amylase (in your saliva) denature and doesn't work.