Biology STAAR Learning Luau - RC 2

Eight components present in nucleic acids are listed in the box. Which components bond with adenine in a section of double-stranded DNA?

• 1, 3, 5, and 6 only

• 3 and 5 only

• 2 and 4 only

• 3, 4, 7, and 8 only

Students are modeling mRNA during the process of protein synthesis. Which answer choice correctly describes the model of the mRNA strand being transcribed?

• The mRNA strand is complementary to the DNA template strand; however, uracil instead of adenine is paired with thymine.

• The mRNA strand is complementary to the DNA template strand; however, uracil instead of thymine is paired with adenine.

• The mRNA strand is an exact copy of the DNA template strand; however, uracil instead of adenine is paired with thymine.

• The mRNA strand is an exact copy of the DNA template strand; however, uracil instead of thymine is paired with adenine.

Tags

NGSS.HS-LS1-1

Mice have two unlinked allele pairs that affect fur color. The table shows how allele pairs affect fur color. The term “agouti” describes fur with pigmentation that changes in each hair from the shaft to the tip, giving the fur a banded appearance. Mice with the aa allele pair are albino, regardless of the second allele-pair combination.

What is the probability of albinism in the offspring of a cross between two mice with AaBb alleles?

• 1/16

• 3/16

• 4/16

• 9/16

Tags

NGSS.HS-LS3-2

NGSS.HS-LS3-3

CRISPR-Cas9 is a genetic modification technique that edits parts of the genome of an organism. Using this technique scientists can add, remove, or modify sections of the DNA sequence.

How can scientists use this technique to control gene expression?

• By activating or deactivating specific genes

• By calculating the number of genes different organisms produce

• By identifying how closely related one individual is to another

• By determining the number of chromosomes in an organism

The inheritance pattern for an autosomal dominant trait is shown in the pedigree. Shaded symbols represent individuals that express the dominant trait.

Based on this pedigree, what are the most likely genotypes of individuals I-1 and I-2?

• I-1: aa I-2: Aa

• I-1: AA I-2: Aa

• I-1: Aa I-2: aa

• I-1: aa I-2: AA

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

model shows a mutation to a partial sequence of bases in a gene.

Which type of mutation does the model demonstrate?

• Deletion

• Insertion

• Substitution

• Translocation

Tags

NGSS.HS-LS3-2

Exposure to the building material asbestos has been linked to certain types of cancers. Asbestos causes mutations in the p53 gene, which controls tumor suppression.

Which statement best explains why people with cancer due to asbestos exposure do not pass the mutation on to their offspring?

• The mutation occurred in gametic cells.

• The mutation occurred in somatic cells.

• The mutation is recessive.

• The mutation is sex-linked.

Which of these components are found in the cells of all living organisms?

• Estrogen and testosterone

• Hemoglobin and lymphocytes

• Cytosine and guanine

• Cellulose and chlorophyll

Tags

NGSS.MS-LS1-1

NGSS.MS-LS1-2

Gametes produced by an organism contain a combination of genes from that organism. In every gamete, this combination is —

• the same because it is created from the same DNA

• the same because chromosomes are copied prior to meiosis

• different due to DNA replication prior to mitosis

• different due to independent assortment during meiosis

Tags

NGSS.HS-LS3-2

A segment of a DNA strand is shown.

3’ AGGTCAGGT 5’

Which of these is the correct complementary DNA strand for the segment shown?

• 5’ AGGTCAGGT 3’

• 5’ ACCUGAGGU 3’

• 5’ TGGACTGGA 3’

• 5’ TCCAGTCCA 3’