Unit 1 DNA and Proteins

Question 1

Question 1- What do we call the shape of the DNA molecule.

Answer 1

Answer - A double stranded helix

Question 2

Question 2- What is the function of DNA?

Answer 2

Answer. DNA carries the genetic information for making proteins.

Question 3

Question 3 - What do we call the sub units of DNA

Answer 3

Answer - Bases

Question 4

Question 4 Name the four base

Answer 4

The four bases: adenine, cytosine, guanine and thymine

Question 5

Question 5 - The bases for pairs. The pairing is given a particular name . What is this name?

Answer 5

Answer - Complimentary base pairs.

Question 6

Question 6 - What are the complimentary base pairs?

Answer 6

(A, C, G and T) make up the genetic code. A is always paired with T and C is always paired with G.

Question 7

Question 7- What does the base sequence determine?

Answer 7

Answer- The base sequence determines amino acid sequence in proteins

Question 8

Question 8- What is a gene?

Answer 8

Answer -A gene is a section of DNA which codes for a protein.

Question 9

Question 9. Where is DNA located and where are proteins made?

Answer 9

Answer- DNA is located in the nucleus ,proteins are assembled on a ribosme in the cytoplasm.

Question 10

Question 10. How do we get the information on the gene from the nucleus to the ribosome.

Answer 10

Answer - Messenger RNA (mRNA) is a molecule which carries a complementary copy of the genetic code from the DNA, in the nucleus, to a ribosome,

Question 11

Question 11- How many bases code for an amnio acid?

Answer 11

Question 12

Question 11- Describe Protein Synthesis

Answer 12

Question 13

Question 12 . Why do we have such a large variety of Proteins?

Answer 13

Answer-

The variety of protein shapes and functions arises from the sequence of amino acids.

Question 14

Question 14- state the functions of proteins

Answer 14

Answer - Proteins have many functions such as;

Structural

Hormones,

Antibodies

Receptors.

Enzymes,

Question 15

Question 15 -What is the function of an enzyme

Answer 15

Answer - Enzymes function as biological catalysts and are made by all living cells.

Question 16

Question 16 What role do enzymes play within cells?

Answer 16

Answer- Enzymes speed up cellular reactions

Question 17

Question 17 - What effect do enzymes have on the reaction?

Answer 17

Answer- enzymes are unchanged in the process

Question 18

Question 18 - What is the name of the molecule that the enzyme reacts with?

Answer 18

Answer - substrate

Question 19

Question 19 - Which part of the enzyme does the substrate bind to ?

Answer 19

Answer - The active site

Question 20

Question 20 - What can you say about the active site and the substrate?

Answer 20

Answer - the shape of the active site of an enzyme molecule is complementary to its specific substrate

Question 21

Question 21 - What does enzyme action result in?

Answer 21

Answer - enzyme action results in product(s)

Question 22

Name the type of reaction in each picture

Answer 22

Answer - Blue picture degration reaction. White picture synthesis reaction

Question 23

Question 23- What does the picture tell you?

Answer 23

Answer - the pictures tell us that enzymes have an optimum pH and temperature. These are the conditions in which the enzymes wok best.

Question 24

Question 24- Explain the effect of temperature on the rate of an enzyme catalysed reaction

Answer 24

Answer;

• At low temperatures the rate of an enzyme catalysed reation is low.
• At high temperatures the rate of an enzyme catalysed reaction is low. This is because the active site is denatured. The shape of the active site has changed. The substrate no longer fits the active site and so the reaction canm not take place.