Scientists develop a genetically modified plant species that has a nonfunctional protein. The protein is necessary for the plant to use nitrogen. The species has a single mutation in a gene.

Question

What does this tell us about the relationship between DNA and proteins?

(1 point)
Responses

Mutations in DNA are always harmful to organisms.
Mutations in DNA are always harmful to organisms.

Nitrogen is vital for plant species survival.
Nitrogen is vital for plant species survival.

Changes in DNA can affect protein function.
Changes in DNA can affect protein function.

Proteins are not related to DNA.

Answer 1

The correct response is:

Changes in DNA can affect protein function.

This statement accurately reflects the relationship between DNA and proteins, as mutations in DNA can lead to changes in the structure and function of proteins, as seen in the genetically modified plant species with a nonfunctional protein necessary for nitrogen utilization.

Answer 2

The mutation shown in the sequence can be categorized as which type?

Original DNA sequence:

A T A C G G T A G C A A
T A T G C C A T C G T T
Mutated DNA sequence:

A T A C G G T A G A A
T A T G C C A T C T T
(1 point)
Responses

chromosomal mutation
chromosomal mutation

substitution mutation
substitution mutation

insertion mutation
insertion mutation

deletion mutation
deletion mutation
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Answer 3

The mutation shown in the sequence is a substitution mutation.

In the original DNA sequence, there is an adenine (A) at the corresponding position in the mutated sequence where it has been changed to guanine (G). This change from one base to another is characteristic of a substitution mutation.

Answer 4

A student is studying the following model of DNA.

A strand of DNA that has exons and introns. The exons are labeled as coding regions. The introns are labeled as non-coding regions.

The student learns that some of the non-coding regions have a high concentration of repressors bound to them.

Which question should the student ask to further understand the role of these non-coding regions in gene regulation?

(1 point)
Responses

How do these non-coding regions interact with DNA polymerase during replication?
How do these non-coding regions interact with DNA polymerase during replication?

What are the sequences of these non-coding regions, and how do they compare to known repressors?
What are the sequences of these non-coding regions, and how do they compare to known repressors?

How are these non-coding regions transcribed into mRNA
How are these non-coding regions transcribed into mRNA

Do these non-coding regions affect the structure of the DNA double helix?

Answer 5

The most relevant question for the student to ask in order to further understand the role of these non-coding regions in gene regulation is:

What are the sequences of these non-coding regions, and how do they compare to known repressors?

This question focuses on understanding the specific sequences that may be involved in binding repressors and regulating gene expression, which is central to the study of gene regulation.

Answer 6

A tall, heterozygous pea plant is cross-pollinated with another tall, heterozygous pea plant. Use a Punnett square to determine the probability that the offspring is a tall, homozygous pea plant.(1 point)
Responses

75%
75%

0%
0%

50%
50%

25%

Answer 7

To determine the probability of producing a tall, homozygous pea plant from a cross between two tall, heterozygous pea plants (Tt x Tt), we can use a Punnett square.

Alleles:

• T = tall (dominant)
• t = short (recessive)

Cross: Tt x Tt

Setting up the Punnett square:

| | T | t | |-----|-----|-----| | T | TT | Tt | | t | Tt | tt |

Results from the Punnett Square:

• TT (tall, homozygous) = 1
• Tt (tall, heterozygous) = 2
• tt (short, homozygous) = 1

Total Combinations:

• TT: 1
• Tt: 2
• tt: 1
• Total = 4 (1 TT + 2 Tt + 1 tt)

Probability of homozygous tall (TT):

• 1 out of 4 = 25%

Therefore, the probability that the offspring is a tall, homozygous pea plant is 25%.

Answer 8

In a study on human height, researchers found that identical twins raised in different countries often have different heights as adults. What does this suggest about the traits, such as height, in humans?(1 point)
Responses

Height is determined solely by environmental factors.
Height is determined solely by environmental factors.

The differences in height are random and not influenced by environmental and genetic factors.
The differences in height are random and not influenced by environmental and genetic factors.

Both environmental factors and genetic factors influence height.
Both environmental factors and genetic factors influence height.

Height is determined solely by genetic factors.

Answer 9

The correct response is:

Both environmental factors and genetic factors influence height.

The observation that identical twins raised in different countries can have different heights suggests that, while genetics play a significant role in determining height, environmental factors (such as nutrition, lifestyle, and overall health) also have a considerable influence.

Answer 10

SARS is a respiratory illness caused by SARS-CoV-1, a coronavirus. It belongs to the same family of viruses that cause common colds.

Streptococcus pneumoniae is a bacterium that causes pneumonia. Pneumonia is an illness that causes fluid buildup in the lungs.

Which of the following statements correctly identifies the characteristics of SARS-CoV-1 and Streptococcus pneumoniae?

(1 point)
Responses

Neither can replicate independently.
Neither can replicate independently.

Both can replicate independently.
Both can replicate independently.

Streptococcus pneumoniae can replicate independently, but SARS-CoV-1 requires a host cell to replicate.
Streptococcus pneumoniae can replicate independently, but SARS-CoV-1 requires a host cell to replicate.

SARS-CoV-1 can replicate independently, but Streptococcus pneumoniae requires a host cell to replicate.

Answer 11

The correct response is:

Streptococcus pneumoniae can replicate independently, but SARS-CoV-1 requires a host cell to replicate.

Streptococcus pneumoniae is a bacterium, which can reproduce on its own through binary fission. In contrast, SARS-CoV-1 is a virus that requires a host cell to replicate, as viruses cannot reproduce independently and must hijack the cellular machinery of a host organism to make copies of themselves.