Cc

Question 1

What is pleiotropy?

Answer 1

A gene impacting one or more characteristics of an organism

One gene can influence multiple traits.

Question 2

What is the genetic basis of sickle cell disease?

Answer 2

A mutation from Glu to Val, changing RBC shape from round to sickle

This shape prevents hemoglobin from effectively carrying oxygen.

Question 3

What is anemia?

Answer 3

A condition characterized by low iron and low oxygen transport

It can lead to heart failure and kidney damage.

Question 4

What type of genetic disorder is sickle cell disease?

Answer 4

A recessive disorder

Both parents must be carriers for a child to inherit the trait.

Question 5

Define monogenic traits.

Answer 5

Traits determined by one gene

Examples include certain single-gene disorders.

Question 6

Define polygenic traits.

Answer 6

Traits determined by more than one gene

Examples include eye color, height, and skin color.

Question 7

What are the two parts of a chromosome arm?

Answer 7

P (shorter) and Q (longer)

The P arm is shorter than the Q arm.

Question 8

Who is Gregor Mendel and what did he study?

Answer 8

He used peas to discover traits

Mendel focused on flower color and pea shape/color.

Question 9

What is the definition of a gene?

Answer 9

Information or code for RNA or proteins

Genes are located on chromosomes.

Question 10

What is an allele?

Answer 10

A variant of a gene

There are two copies of alleles: recessive (r) and dominant (R).

Question 11

What does homozygous mean?

Answer 11

Having two alleles of the same gene

Examples: RR (homozygous dominant) or rr (homozygous recessive).

Question 12

What is a monohybrid cross?

Answer 12

A genetic cross between individuals differing in one trait

It helps illustrate inheritance patterns.

Question 13

What distinguishes sex-linked traits from autosomal traits?

Answer 13

Sex-linked traits are located on sex chromosomes

Most are found on the X chromosome.

Question 14

What is Hardy-Weinberg Equilibrium?

Answer 14

A state where allele and genotype frequencies remain constant in a population

This occurs unless evolutionary forces act on the population.

Question 15

What is the Hardy-Weinberg equation for allele frequency?

Answer 15

P + q = 1

P is the frequency of the dominant allele, and q is the frequency of the recessive allele.

Question 16

What does the Hardy-Weinberg genotype frequency equation represent?

Answer 16

2^p + 2pq + 2^q = 1

P^2 is homozygous dominant, 2pq is heterozygous, and q^2 is homozygous recessive.

Question 17

Define incomplete dominance.

Answer 17

A genetic situation where neither allele is completely dominant

This results in a phenotype that is a blend of both alleles.

Question 18

What is codominance?

Answer 18

A genetic situation where both alleles are fully expressed

Neither allele overshadows the other.

Question 19

What is a mutation?

Answer 19

A change in the DNA sequence that can affect protein structure

Mutations can be neutral, beneficial, or harmful.

Question 20

What is a silent mutation?

Answer 20

A mutation that does not affect the amino acid sequence

It may result from changes that lead to the same amino acid.

Question 21

What is a missense mutation?

Answer 21

A mutation that causes a change in the amino acid sequence

Example: the mutation causing sickle cell disease.

Question 22

What is a nonsense mutation?

Answer 22

A mutation that introduces an abrupt stop codon

This can lead to truncated proteins.

Question 23

What does the term ‘locus’ refer to?

Answer 23

The location of a gene on a chromosome

It helps in identifying where specific traits are determined.