4: Inheritance and Selection

Question 1

Define allele

Answer 1

One of the different forms of a particular gene

Question 2

Define genotype

Answer 2

The genetic constitution of an organism, it describes all the alleles that an organism contains

Question 3

Define phenotype

Answer 3

The observable characteristics of an organism and the result of the interaction between the expression of the genotype and the environment

Question 4

Define dominant

Answer 4

An allele whose characteristic appears in the phenotype even when there’s only one copy present

Question 5

Define recessive

Answer 5

An allele whole characteristic only appears in the phenotype if two copies are present

Question 6

Define co dominant

Answer 6

Alleles that are both expressed in the phenotype

Question 7

Define homozygote

Answer 7

An organism that carries two copies of the same allel

Question 8

Define heterozygote

Answer 8

An organism that carries two different alleles

Question 9

What is meant by a sex linked gene?

Answer 9

Any gene that is carried on either the X or Y chromosome

Question 10

Define gene

Answer 10

A sequence of bases on DNA that codes of a particular polypeptide

Question 15

How to produce a plant tissue culture

Answer 15

A single totipotent stem cells is taken from the growing area
The cell is place on a sterile growth medium
The plant stem cell will grow and divide into a mass of unspecialised cells
If the conditions are suitable the cells will mature into specialised cells
The cells grow and specialise to form a plant organ or an entire plant depending on the growth factors used

Question 20

Two types of selection

Answer 20

Directional and stabilising

Question 21

What does the hardy-Weinberg principle predict?

Answer 21

The frequencies of alleles in a population won’t change from one generation to the next

Question 22

What does the hardy-Weinberg principle rely on?

Answer 22

The mutations
No selection
Mating is random
Population is large
No migration