Inheritance/Genetics

Question 1

What is an allele?

Answer 1

A version of a gene.

Question 2

What does homozygous mean?

Answer 2

Both alleles are the same.

Question 3

What is a genotype?

Answer 3

The alleles of the organism.

Question 3

What does heterozygous mean?

Answer 3

Alleles are different in an individual.

Question 4

What is a phenotype?

Answer 4

The physical expression of a gene.

Question 5

What does dominant mean?

Answer 5

The allele expressed in the heterozygote.

Question 6

What does recessive mean?

Answer 6

The allele only expressed when homozygous.

Question 7

What is co-dominance?

Answer 7

When both alleles are expressed in the phenotype.

Question 8

What term should you use when crossing over alleles for gametes?

Answer 8

FOIL

(firsts, outsides, insides, lasts)

Question 9

What are the 2 types of variation?

Answer 9

Continuous and discontinuous.

Question 10

What is natural selection?

Answer 10

Those best adapted will survive to reproduce in greater numbers than those less well adapted. They will pass on advantageous alleles to the next generation. Therefore the offspring will tend to inherit advantageous characteristics.

Question 11

What increases chance of mutation?

Answer 11

-Ionising radiation like x-rays or gamma rays
-Chemicals called mutagens like chemicals in tobacco

Question 12

Define mutation?

Answer 12

A change to the base sequence of DNA.

Question 13

What phrase do you use in antibiotic resistance?

Answer 13

MAVARIPS

Question 14

What is DNA like in eukaryotes?

Answer 14

Found within the nucleus as linear chromosomes.

Question 15

What is DNA like in prokaryotes?

Answer 15

In the cytoplasm in the form of a circular chromosome and many small plasmids.

Question 16

How are nucleotides joined together in both DNA and RNA?

Answer 16

By covalent bonds between the sugar of one nucleotide and the phosphate group of the next nucleotide.

Question 17

Give 3 differences of DNA and RNA:

Answer 17

1) RNA is single stranded, DNA is double stranded
2) RNA has a sugar called ribose, while DNA has a sugar called deoxyribose
3) RNA has the base uracil while DNA has the base thymine.

Question 18

What is mRNA?

Answer 18

-Messenger RNA
-Found in nucleus
-Made in transcription
-Carries the code for building a specific protein from the nucleus to the ribosomes

Question 19

What is tRNA?

Answer 19

-Transfer RNA
-Found in cytoplasm
-Made in translation
-Picks up amino acids from cytoplasm and brings them into position on the surface of a ribosome where they can be joined together in a specific order to make a specific protein

Question 20

What is a gene?

Answer 20

A length of DNA which codes for a protein.

Question 21

What do alleles do?

Answer 21

Code for different forms of a protein.

Question 22

What is a genome?

Answer 22

One copy of all an organism’s DNA.

Question 23

What is polygenic inheritance?

Answer 23

When some characteristics are controlled by several genes which influence each other.

Question 24

What is polygenic inheritance more likely to show?

Answer 24

Continuous variation.