Genetics

Question 1

What is the structure of DNA?

Answer 1

DNA is shaped in a double-helix form and made up of nucleotides which code for amino acids (Guanine, Cytosine, Thymine, Adenine), deoxyribose sugar, and a phosphate group.

Question 2

What is the primary function of DNA?

Answer 2

It provides the code for all body proteins and our genetic material.

Question 3

What does replication make?

Answer 3

DNA -> DNA

Question 4

What does transcription make?

Answer 4

DNA -> mRNA

Question 5

What does translation make?

Answer 5

mRNA -> polypeptide chain (protein); help of tRNA

Question 6

What happens during DNA replication?

Answer 6

The DNA strand is untwisted and unzipped by helicase, DNA polymerase pairs complementary bases, adds new nucleotides, and proofs the new DNA strand.

Question 7

DNA polymerase?

Answer 7

pairs complementary nucleotides and proof reads new DNA stand

Question 8

What occurs during transcription?

Answer 8

RNA is synthesized from the DNA template with RNA polymerase, forming mRNA which moves out of the nucleus and into the cytoplasm.

Question 9

RNA polymerase?

Answer 9

forms mRNA (functions like DNA polymerase)

Question 10

What is the process of translation?

Answer 10

RNA directs the synthesis of a polypeptide via interaction with tRNA, which contains anticodons complementary to the mRNA codons.

Question 11

What are euploid cells?

Answer 11

Cells that have multiples of the normal number of chromosomes.

Question 11

ribosome?

Answer 11

joins mRNA and tRNA (carries base pairs) for protein synthesis

Question 12

Define polyploidy.

Answer 12

A euploid cell that has more than the diploid number.

Question 13

What is trisomy?

Answer 13

A cell containing 3 copies of one chromosome.

Question 14

What is monosomy?

Answer 14

The presence of only one copy of any chromosome, typically lethal.

Question 15

What is nondisjunction?

Answer 15

Failure of homologous chromosomes or sister chromatids to separate normally during mitosis or meiosis.

Question 16

What is Turner syndrome?

Answer 16

A condition characterized by having only one X chromosome.

Question 17

What is Klinefelter syndrome?

Answer 17

A condition characterized by the presence of an extra X chromosome (XXY).

Question 18

What is a deletion in chromosome structure alterations?

Answer 18

Chromosome breakage or loss of DNA.

Question 19

What is codominance?

Answer 19

A genetic scenario where both alleles are expressed.

Question 20

Define homozygous.

Answer 20

When genes are identical.

Question 21

Define heterozygous.

Answer 21

When genes are different.

Question 22

What is a karyotype?

Answer 22

An individual’s complete set of chromosomes.

Question 23

What is a genotype?

Answer 23

The specific set of alleles someone has.

Question 24

What is a phenotype?

Answer 24

How the genotype gets expressed, resulting from interaction with the environment.

Question 25

What is Cri du chat an example of?

Answer 25

deletion of chom. 5; not passed down

Question 26

what is cystic fibrosis an example of?

Answer 26

autosomal recessive disorder

Question 27

What is down syndrome an example of?

Answer 27

nondisjunction - trisomy 21

Question 28

What is Duchenne muscular dystrophy an example of?

Answer 28

X-linked recessive

Question 29

What is Huntington's disease an example of?

Answer 29

Autosomal dominant.

Question 30

What is the difference between autosomal dominant and autosomal recessive disorders?

Answer 30

Autosomal dominant requires only one affected allele to express the disease; autosomal recessive requires two affected alleles.

Question 31

What is penetrance?

Answer 31

The percentage of individuals with a specific genotype who express the expected phenotype.

Question 32

What is expressivity?

Answer 32

The variation in a phenotype associated with a particular genotype.

Question 33

What environmental factors influence hypertension?

Answer 33

Sodium intake, lack of exercise, stress, obesity.

Question 34

What is the inheritance pattern of sex-linked disorders?

Answer 34

Usually expressed in males; affected males cannot pass to sons but can to daughters.

Question 35

Are diseases multifactorial?

Answer 35

YES diabetes, hypertension, breast cancer. all have genetic and environmental components