Biology Inheritance

Question 1

Where in the cells is DNA found?

Answer 1

The nucleus

Question 2

Why is DNA important?

Answer 2

Determines our characteristics

Question 3

What do the initials DNA stand for?

Answer 3

Deoxyribose nucleic acid

Question 4

Describe the structure of a DNA molecules

Answer 4

2 polynucleotide strands, joined by complementary nitrogenous bases, coiled round in a spiral called a double helix

Question 5

What is a gene?

Answer 5

A section of DNA which codes for a unit of information

Question 6

Name the 4 types of nitrogenous base which can be present in a nucleotide.

Answer 6

Adenine
Thymine
Cytosine
Guanine

Question 7

The bases on one polynucleotide chain always pair with a complementary base on the opposite chain. Known as complementary base pairing. State which bases pair with which.

Answer 7

Adenine with Thymine
Cytosine with Guanine

Question 8

What type of bond holds the bases together?

Answer 8

Hydrogen bonds

Question 9

Here is part of a strand write down the sequence of its complementary strand : ATGTTTACCGA

Answer 9

TACAAATGGCT

Question 10

What are the two main stages called in protein synthesis?

Answer 10

1. Transcription - A gene is transcribed into a single stranded mRNA copy.
2. Translation - mRNA is translated into a protein using tRNA and ribosomes.

Question 11

How to convert DNA to Protein.
1st step

Answer 11

A single stranded mRNA (messenger RNA) copy of the gene is made using only ONE DNA strand as a template (the template strand). This stage is transcription.

Question 12

How to convert DNA to Protein.
2nd step

Answer 12

mRNA passes out of the nucleus and into the cytoplasm where it binds to a ribosome

Question 13

How to convert DNA to Protein.
3rd step

Answer 13

The ribosome moves along the mRNA and reads the mRNA codons .