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Flashcards in First Test Deck (13):
1

Define natural selection

the process whereby organisms better adapted to their environment tend to survive and produce more offspring.

2

Evolution

Change in the characteristics of a species over many generations

3

An example of natural selection

In a habitat there are red bugs and green bugs. The birds prefer the taste of the red bugs, so soon there are many green bugs and few red bugs. The green bugs reproduce and make more green bugs and eventually there are no more red bugs.

4

Crossed breeding

Selective breeding by combining a desirable feature of one individual with another in the offspring

5

Phenotype

The observable characteristics eg tall

6

Genotype

The allele information eg Tt

7

What is dominate disease

this occurs when a person has one disease allele but it over powers the other normal gene. The person is affected by the disease.

8

Recessive disease

This occurs only when two of the abnormal gene are present (homozygous). One from each parent.

9

Define heterozygous

Heterozygous- allele information that is different. Eg Aa

10

Define homozygous

Homozygous- allele information that is the same. Eg aa or AA

11

Define carrier

Carrier- the person that has a specific trait and carries it to someone else in their family.

12

Define true breeding

Pure bred an organism that always pass down similar traits

13

Define gene

A section of DNA that codes for a particular characteristic.