Unit 1

Question 1

How are DNA chains held together in a double helix?

Answer 1

Through hydrogen bonds.

Question 2

What is transcription?

Answer 2

Gene expression. Transcription copies the sequence of part of one strand of a DNA molecule into a messenger ribonucleic acid (RNA).

Question 3

What is messenger ribonucleic acid (RNA)?

Answer 3

A copy of a DNA strand, contains uracil (U) in place of the thymine (T) in DNA.

Question 4

What is translation?

Answer 4

In translation, each three RNA bases in a row attract another type of RNA that functions as a connector, bringing in a particular amino acid. The amino acids align and link, forming a protein.

Question 5

What do proteins do?

Answer 5

Proteins provide the traits associated with genes.

Question 6

What are the four nitrogenous bases of DNA?

Answer 6

Adenine (A), Thymine (T), Cytosine (C), and Guanine (G).
A-T; C-G

Question 7

What are alleles?

Answer 7

The same protein-encoding gene may vary slightly in DNA base sequences from person to person. These gene variants are called alleles. The changes in DNA sequence that distinguish alleles arise by mutation.

Question 8

What are chromosomes?

Answer 8

The DNA sequences of the human genome are grouped among 23 structures called chromosomes.

Question 9

What is a somatic cell?

Answer 9

A non-sex cell. In humans they have 23 pairs of chromosomes.

Question 10

What is an autosome?

Answer 10

A chromosome that does not differ between the sexes. 22 or the 23 chromosomes are autosomes.

Question 11

What are sex chromosomes?

Answer 11

There are two types of sex chromosomes, X and Y. X determines female, Y determines male.

Question 12

What is a karyotype?

Answer 12

A chart of chromosomes, usually listed in order of largest to smallest.

Question 13

What is a complex trait?

Answer 13

Most characteristics are complex traits, which means they are determined by one or more genes and/or environmental factors. The more factors contribute to a trait or illness, the more difficult it is to predict the risk of occurrence in a particular family member.

Question 14

What is differentiation?

Answer 14

The specialization of distinctive cell types.

Question 15

What is a stem cell?

Answer 15

A cell that can divide to yield another stem cell (self-renew) and a cell that differentiates.

Question 16

What is genotype?

Answer 16

Refers to the underlaying DNA instructions (alleles present).

Question 17

What is phenotype?

Answer 17

Phenotype is the visible trait, biochemical change, or effect on health (alleles expressed).

Question 18

What is a pedigree?

Answer 18

A chart which depicts the members of a family and indicates which individuals have particular inherited traits.

Question 19

What is pharmacogenetics?

Answer 19

A precision medicine approach which consults DNA information to select drugs that are most likely to work and least likely to have side effects in a particular individual.

Question 20

What is exome sequencing?

Answer 20

Exome sequencing determines the order of the DNA bases of all parts of the genome that encode proteins. It can be used to compare against databases of gene variants and specific phenotypes, such as diseases.

Question 21

What is metagenomics?

Answer 21

A field which describes much of the invisible living world by sequencing all of the DNA in a habitat, such as soil, an insect’s gut, garbage, or a volume of captured air over a city.