Unit 2

Question 1

Humans are diploid organisms, meaning

Answer 1

we have two alleles of each gene

Question 2

We have two alleles because

Answer 2

you inherited one version of each chromosome from each parent

Question 3

Each chromosome contains one allele of

Answer 3

each of the genes on that chromosome

Question 4

Every gene in our genome is one of the ___ chromosomes

Answer 4

23

Question 5

Gene (definition)

Answer 5

segment of DNA that is transcribed

Question 6

Genes are _____

Answer 6

information; they do not do or make anything

Question 7

Each member of the chromosome pair has the same genes (T/F)

Answer 7

true

Question 8

Two alleles can be the same or different depending on the differences in

Answer 8

DNA sequences

Question 9

Homozygous (definition)

Answer 9

when an individual’s two alleles are the same

Question 10

Heterozygous (definition)

Answer 10

when an individual’s two alleles are different

Question 11

All organisms have ____ containing ____ found in ____

Answer 11

cells; DNA; chromosomes

Question 12

In a chromosome after duplication, there are 2 DNA molecules (T/F)

Answer 12

true

Question 13

What bridges genotypes and phenotypes?

Answer 13

proteins

Question 14

Most genes are ____-coding

Answer 14

protein

Question 15

Is the protein-coding part the only part of a gene?

Answer 15

No. Most DNA in the genome do not code for proteins

Question 16

Protein-coding genes have a ______ and a _____

Answer 16

coding region; noncoding region

Question 17

Do genes make proteins?

Answer 17

No. They encode proteins.

Question 18

If each chromosome version has an allele of the gene, are both alleles transcribed or just one?

Answer 18

Both alleles are transcribed AND both protein versions are produced

Question 19

In the HD case study, what was the phenotype resulting from the difference in normal and HD alleles of the Hungtingtin’s gene?

Answer 19

the structure of the brain is a phenotype affected by this

Question 20

The behavioral changes of HD patients (Case Study 1) are phenotypes affected by

Answer 20

the difference in normal and HD alleles of the Hungtintin’s gene

Question 21

What are the two types of information in the genome?

Answer 21

instructions for how to make gene products
instructions for when, how much, and in what cells to transcribe genes

Question 22

The transcription level of a gene varies depending on

Answer 22

cell type
development
environment

Question 23

What is the key factor for controlling the level of transcription of a gene?

Answer 23

noncoding DNA

Question 24

Why is regulation of transcription level important?

Answer 24

it allows different cells of the same organism to do different things

Question 25

What is a gene regulatory switch?

Answer 25

a short sequence (5-20 base pairs) of DNA in the noncoding region where transcriptional regulatory protein binds

Question 26

Differences in transcriptional regulation are key to

Answer 26

the diversity of form among species

Question 27

mRNA is produced by transcription from the coding DNA of a gene but not the noncoding DNA and this mRNA is translated to make a protein (T/F)

Answer 27

TRUE

Question 28

mRNA is produced by transcription from both the noncoding and coding DNA of a gene and both of these mRNAs are translated to make proteins (T/F)

Answer 28

FALSE

Question 29

What is a gene regulatory switch made of?

Answer 29

DNA only

Question 30

Transcriptional regulatory proteins physically bind to

Answer 30

noncoding DNA

Question 31

In a plant that has one teosinte parent and one maize parent (Case 3) ___ protein(s) is/are produced

Answer 31

both

Question 32

Ignore

Answer 32

Ignore

Question 33

Every human has two alleles of the lactase gene (T/F)

Answer 33

TRUE

Question 34

Every human's two lactase alleles are the same in each of their cells (T/F)

Answer 34

TRUE

Question 35

Each lactase allele has a coding part and a noncoding part (T/F)

Answer 35

TRUE

Question 36

The lactase alleles may differ in DNA sequences in their coding parts and/or noncoding parts (T/F)

Answer 36

TRUE

Question 37

Mutations are referred to as

Answer 37

"the factory of variation production"

Question 38

Mutation (definition)

Answer 38

a change in the nucleotides of a DNA molecule

Question 39

Mutations are the original source of [all/most/some/no] genetic variation

Answer 39

all

Question 40

Mutations occur when

Answer 40

mistakes are made in DNA replication or when DNA damage is not properly repaired

Question 41

Mutations are [constantly/usually/rarely/never] occurring

Answer 41

constantly

Question 42

In the absence of chemicals and radiation would mutation still occur?

Answer 42

Yes. Mutations occur randomly and are unavoidable. Chemicals and radiation are not common causes of mutation in nature or human populations

Question 43

Does it matter where in the genome mutations occur?

Answer 43

Yes. Mutations in the coding region can affect amino acid sequence and mutations in the noncoding region can affect transcription levels.

Question 44

Germ-line mutations (definition)

Answer 44

mutations that occur in the cells giving rise to sperm & egg cells (gametes)

Question 45

Somatic mutations (definition)

Answer 45

mutations that occur in cells of the body during or after development

Question 46

Which occurs more in multicellular organisms, somatic mutations or germ-line mutations?

Answer 46

Somatic mutations occur far more than germ-line mutations because we have more somatic cells than gametes.

Question 47

Do somatic mutations pass down to offspring?

Answer 47

No

Question 48

Do germ-line mutations pass down to offspring?

Answer 48

Possibly

Question 49

Somatic mutations are mostly harmless aside from

Answer 49

cancer cells

Question 50

Each gametes contains __ alleles of each gene

Answer 50

one

Question 51

A typical mutation that occur in a human cell is likely to have ____ effect and likely to occur in ____ region

Answer 51

no effect; noncoding region

Question 52

A mutation that occurs in the DNA of a skin cell on your back [can/cannot] be inherited by your children

Answer 52

cannot