U2 Questions + Examples

Question 1

You overhear the following conversation between two brothers (full siblings):

Brother 1: “I inherited genes from mom causing me to have blue eyes and you did not.”

Brother 2: “That is not a correct statement”

Which of the following changes would have made Brother 1’s statement more correct?

1) Changing “inherited” to “received”
2) Changing “genes” to “alleles”
3) Changing “genes” to “chromosomes”
4) None of the above

Answer 1

2) Changing “genes” to “alleles”

–> Both brothers inherited the same genes, but they inherited different alleles of the gene

Question 2

Which of the following is true regarding “disease genes”?

1) Only certain people have “disease genes”

2) “Disease genes” can only be inherited from a parent who is affected by a disease

3) A healthy individual does not carry any “disease genes”

4) Different alleles of “disease genes” can influence a person’s likelihood of being affected by a disease

Answer 2

4) Different alleles of “disease genes” can influence a person’s likelihood of being affected by a disease

Question 3

When a biologist is talking about the level of gene expression, they are usually talking about:

1) How strongly expressed a phenotype associated with the gene is

2) How strongly reduced a normal trait is because of a mutation in the gene

3) The number of genes that are involved in producing a trait

4) The level of transcription of a gene

5) None of the above

Answer 3

4) The level of transcription of a gene

Question 4

In the “switches” conceptual model of gene regulation, which things act as switches?

1) Non-coding DNA sequences

2) messenger RNAs

3) Codons

4) Cells

5) Enzymes

Answer 4

1) Non-coding DNA sequences

Question 5

How are genes and alleles related?

1) A gene codes for alleles

2) Alleles and genes are the same thing

3) Diploid organisms have two genes for each allele

4) A child has the same genes as his/her mother but may have different alleles

Answer 5

4) A child has the same genes as his/her mother but may have different alleles

Question 6

Chromosomes that are “X-shaped” represent duplicated (replicated) chromosomes

Answer 6

True

Question 7

mRNA, proteins, and DNA sequences all influence phenotypes

Answer 7

True

Question 8

Alleles are different versions of a protein

Answer 8

False

Question 9

Similarity in a phenotype between parent and offspring may not be due to inherited genetic factors

Answer 9

True

Question 10

How many alleles of each gene (that is not on a sex chromosome) did you inherit from your father?

1) 0
2) 0.5
3) 1
4) 2
5) It depends on the gene

Answer 10

3) 1 allele

Question 11

Each body cell of a person (any cell that is not a gamete) has the same number of each chromosome

Answer 11

True

Question 12

The sequence of DNA nucleotides in an organism’s genome is a blueprint for the phenotype of the organism

Answer 12

False

–> Many other factors can also affect phenotype

Question 13

Different alleles of a gene can be present in the same individual

Answer 13

True

Question 14

Which of the following is true about how genes influence phenotypes?

1) Genes code for proteins and proteins influence cell functioning

2) The phenotypic variation among humans largely results from their different genes

3) Genes provide a perfect molecular blueprint for an organism’s phenotypes

4) The genotypes of different individuals make different phenotypes

Answer 14

1) Genes code for proteins and proteins influence cell functioning

Question 15

Every human passes many somatic mutations to their offspring

Answer 15

False

Question 16

A gene encoding an enzyme is transcribed in flower petal cells but is not transcribed in root cells of the same plant. What is the most likely explanation of this phenomenon?

1) Flower cells have the gene in their genomes but root cells do not

2) The gene has non-coding sequences that enable it to be transcribed in flower cells but not in root cells

3) Flower cells have proteins that bind to non-coding sequences of the gene and help turn on transcription but root cells do not

4) All of the above are true

5) B and C are true but not A

Answer 16

5) B and C are true but not A

Question 17

Both germ-line and somatic mutations can be passed on to offspring

Answer 17

False

Question 18

Which of the following is the same between a person’s fat cell and their blood vessel cell?

1) The number of alleles that are in the nucleus of the cells.

2) The types of proteins that are made

3) The amounts of different proteins that are made

4) The types of messenger RNA that are made

Answer 18

1) The number of alleles that are in the nucleus of the cells.

Question 19

Non-coding DNA contains information that is directly relevant to the structure of proteins

Answer 19

False

Question 20

Some organisms do not undergo mutations

Answer 20

False

Question 21

Every human being carries somatic mutations

Answer 21

True

Question 22

Environmental conditions determine which mutations are most likely to occur

Answer 22

False

Question 23

Mutations are extremely rare in living things

Answer 23

False

Question 24

Children inherit two alleles of each gene from each parent

Answer 24

False

Question 25

In humans and most other animals, somatic cells are produced by ___________, while gametes are produced by __________.

Answer 25

Mitosis, Meiosis

Question 26

Pedigree analysis involves making diagrams that can be used to infer hereditary processes

Answer 26

True

Question 27

All mutations are harmful

Answer 27

False

Question 27

Which of the following is true about mutations?

1) Mutations in body cells can be inherited by offspring.

2) Mutations in the noncoding region of a gene can directly impact the structure of the protein.

3) Most mutations are caused by radiation or chemicals in the environment.

4) Some mutations can be beneficial to the organism.

Answer 27

4) Some mutations can be beneficial to the organism.

Question 27

2 daughters of the same parents are expected to have the same alleles (as each other) on most of their chromosomes

Answer 27

False

Question 28

The genome is like an architectural blueprint.

Answer 28

False

Question 29

Which of the following is TRUE regarding inheritance?

1) Children inherit one allele from their mother and one allele from their father for most genes.

2) Children inherit some of their genes (e.g., the huntingtin gene) from their mothers and some of their genes (e.g. a keratin gene) from their fathers.

3) Children inherit body cell mutations that their parents accumulated during their lifetimes.

4) Children inherit “disease genes” only if a parent was affected by a disease.

Answer 29

1) Children inherit one allele from their mother and one allele from their father for most genes.

Question 30

What is the probability that a randomly chosen gamete produced by an individual whose genotype is Hh carries the h allele?

1) 0%
2) 25%
3) 50%
4) 75%
5) 100%

Answer 30

3) 50%

Question 31

In humans and most other animals, the type of cells that result from meiosis are:

1) Zygotes
2) Gametes
3) Chromosomes
4) DNA
5) Gonads

Answer 31

2) Gametes

Question 32

Many phenotypes are affected as much by the environment as they are by inherited factors.

Answer 32

True

Question 33

Mice are often used in human disease research. In these studies, the mice are a type of physical model.

Answer 33

True

Question 34

Two male fruit flies that have the same mother and the same father are expected to have the same genes as both their mother and their father.

Answer 34

True

Question 35

Which of the following is true?

1) Protein coding sequences are harder to find than the transcriptional regulatory sequences because they are rare

2) Protein coding sequences are harder to find than transcriptional regulatory sequences because computer software cannot find them

3) Protein coding sequences are easier to find than transcriptional regulatory sequences because most of the genome codes for proteins

4) Protein coding sequences are easier to find than transcriptional regulatory sequences because they can be found using the genetic code

Answer 35

4) Protein coding sequences are easier to find than transcriptional regulatory sequences because they can be found using the genetic code

Question 36

A gene encoding an enzyme is transcribed in flower petal cells but is not transcribed in root cells of the same plant. What is the most likely explanation of this phenomenon?

1) Flower cells have the gene in their genomes but root cells do not have the gene in their genomes

2) The gene has noncoding sequences that enable it to be transcribed in flower cells but prevent it from being transcribed in root cells

3) Flower cells have proteins that bind to noncoding sequences of the gene and help turn on transcription but root cells do not

4) All of the above are true

5) 2 and 3 are true but not 1

Answer 36

5) 2 and 3 are true but not 1

Question 37

Which of the following is false about mutations?

1) Environmental conditions determine which mutations are most likely to occur

2) Mutations are the origin of all genetic variation in natural populations

3) Most new mutations in an individual will not be inherited by its offspring

4) Toxic chemicals are not a common cause of mutations in living organisms

5) Most mutations are due to errors in DNA replication that are not repaired

Answer 37

1) Environmental conditions determine which mutations are most likely to occur

Question 38

If a person’s two alleles of a gene are the same, then for this gene, the person is:

Answer 38

Homozygous