Biology 6.2.1

Question 1

What is ‘Variation’?

Answer 1

Variation is Defined as Differences Between Individuals of the Same Species.

Question 2

What is ‘Phenotypic Variation’?

Answer 2

Phenotypic Variation is the Difference in Physical Features / Attributes Between Individuals of the Same Species.

Question 3

Phenotypic Variation can be Caused in 2 Main ways: (3)

Answer 3

-Genetic Variation.

-Environmental Variation.

-Combination of Genetic & Environmental Variations.

Question 4

Common Examples of Genetic Variation in Humans Include: (5)

Answer 4

-Blood Group.

-Eye Colour.

-Gender.

-Ability to Roll Tongue.

-Free or Fixed Earlobes.

Question 5

What are the Main Environmental Factors that Can Affect the Characteristics of Organisms within a Species? (5)

Answer 5

-Climate.

-Diet.

-Accidents.

-Culture.

-Lifestyle.

Question 6

What Affect will the Environmental Factor ‘Accidents’ Have on the Organism?

Answer 6

It may leave Scars.

Question 7

What Affect will the Environmental Factors ‘Eating too Much, & Not Leading an Active Lifestyle’ Have on the Organism?

Answer 7

Weight Gain.

Question 8

What Affect will the Environmental Factor ‘Being Raised in a Certain Country’ Have on the Organism?

Answer 8

Speak a Certain Language, with a Certain Accent.

Question 9

What will happen to a Plant that is in the Shade of a Big Tree?

Answer 9

A Plant in the Shade of a Big Tree Will Grow Taller, to Reach More Light.

Question 10

Some Features of a Person Vary, because of a Combination of ___ & ___ Factors.

Answer 10

Genetic, Environmental.

Question 11

Explain an Example of a Feature in Humans that Varies, Based on a Combination of Both Genetic & Environmental Factors. (2)

Answer 11

-Genetic Factor: Tall Parents will Pass Genes to their Children for Height. Their Children have the Genetic Potential to also be Tall.

-Environmental Factor: However, if their Diet is Poor, & they Don’t Lead an Active Lifestyle, they will not Grow very well.

Question 12

Genes Decide what Characteristics we ___, whereas the Surrounding Environment will Affect how these Inherited Characteristics ___ throughout our Lives.

Answer 12

Inherit, Develop.

Question 13

There is Usually ___ Genetic ___ Within a Population of a Species.

Answer 13

Extensive, Variation.

Question 14

What do all Genetic Variants arise from?

Answer 14

All Genetic Variants arise from Mutations.

Question 15

What are ‘Mutations’?

Answer 15

Mutation are Random Genetic Changes that Occur Continuously.

Question 16

Most Mutations Have no ___ on the ___. Why is this?

Answer 16

Effect, Phenotype. This is because the Protein that a Mutated Gene Produces may Work just as well as the Protein from the Non-Mutated Gene.

Question 17

Very Rarely, Mutations Lead to the Development of new ___, and so new ___. If they do, most only have a ___ Effect on the Organism overall.

Answer 17

Allele, Phenotype, Small.

Question 18

What may a Mutation that Affects the Phenotype of an Organism Lead to?

Answer 18

Occasionally, the new Allele, (Caused by the Mutation) that Affects the Phenotype, Gives the Organism a Survival Advantage over other Members of the Species.

Question 19

What may happen if the new Phenotype (Caused by a Mutation) is Better Suited to an Environmental Change?

Answer 19

If the New Phenotype (Caused by a Mutation) is Suited to an Environmental Change, it Can Lead to a Relatively Rapid Change in the Species.

Question 20

Explain an Example of when a New Phenotype (Caused by a Mutation) has led to a New Species. (4)

Answer 20

-A Moth Develops a Mutation, Leading to a Change in its Colour. (Mutation Causes New Allele, Causes New Phenotype).

-This Makes it Blend in Better with the Tree Bark it Lives on, & Less Visible to Predators, therefore Increasing Rate of Survival.

-This Moth has a Survival Advantage, & Breeds More Frequently, therefore Increasing its Chance of Passing on the Mutated Phenotype to the Next Generation of Moths.

-The New Colour Quickly Spreads Throughout the Species.