3.7.1 Inheritance Flashcards Preview

Biology A2 Mr Jones Topics > 3.7.1 Inheritance > Flashcards

Flashcards in 3.7.1 Inheritance Deck (21)
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1
Q

What is a gene ?

A

sequence of bases on a DNA molecule that codes for a protein which results in a characteristic

2
Q

What are alleles ?

A

One or more versions of a gene

3
Q

What differs between each allele?

A

Base order

4
Q

What are diploid organisms ?

A

ones that have 2 copies of each chromosome

5
Q

Give an example of a diploid organism ?

A

Human

6
Q

What are haploid organisms ?

A

Ones that only have one allele for each gene

7
Q

Give an example of a haploid organism ?

A

Gametes

8
Q

What is the locus?

A

Position of a gene on a chromosome

9
Q

What is a genotype ?

A

Genetic constitution of an organism

represents pair of alleles for a characteristic

10
Q

What is a phenotype ?

A

Expression of genetic constitution + its interaction with the environment

11
Q

What are dominant allele ?

A

Ones that are always expressed in the organisms phenotype

12
Q

What are recessive alleles ?

A

One that are only expressed in the homozygous recessive genotype/condition

13
Q

What are codominant allele ?

A

Neither one is recessive so they are both expressed in the phenotype

14
Q

Define homozygous

A

When an organisms carries 2 copies of the same allele

15
Q

Define herterozygous

A

When an organism carries 2 different alleles for a gene

16
Q

What is monohybrid inheritance ?

A

Inheritance of a characteristic controlled by a single gene

17
Q

What is meant by co dominance ?

A

Both alleles are expressed in the phenotype, and neither one is recessive

18
Q

What is meant by multiple alleles ?

A

When there is more than two alleles of the same gene

19
Q

What are dihybrid crosses ?

A

Show the likelihood of offspring inheriting certain combinations of the two characteristics from particular parents

20
Q

What is dihybrid inheritance ?

A

Inheritance of 2 characteristics, which are controlled by different genes

21
Q

What is the ratio for a dihybrid cross with 2 heterozygous parents ?

A

9:3:3:1