STAAR Review Category 2

A mutation is least likely to affect a cell when the mutation—

• reverses the order of bases in a DNA strand

• allows the total number of bases in a DNA sequence to remain the same

• replaces a base with its complementary base

• produces a triplet that codes for the same amino acid as the original triplet

The diagram above shows the process of meiosis. The segregation that occurs during meiosis results in—

• decrease in the total number of cells per organism

• reduction in the number of chromosomes per cell

• single fertilized egg cell

• group of genetically identical cells

Tags

NGSS.HS-LS3-2

The technique known as chromosome painting is the result of scientific research. Scientists use chromosome painting to mark the locations of genes on human chromosomes with fluorescent tags. It is also possible to apply this technique to the chromosomes of many different species. Chromosome painting allows for which of the following?

• A comparison of the genomes of different species

• The sequencing of proteins from many species

• An increase in mutations in many species

• The extraction of amino acids from different species

Tags

NGSS.HS-LS4-1

A section of a nucleic acid is shown below.

The process represented in the diagram produces a molecule that is complementary to the template strand of DNA. What type of molecule is produced?

• New DNA

• Polypeptide

• Messenger RNA

• Carbohydrate

If several pea plants with the genotype TTYy are crossed with pea plants with the genotype Ttyy, what percentage of the offspring will be expected to have the TTYy allele combination?

• 25%

• 40%

• 50%

• 75%

Tags

NGSS.HS-LS3-2

NGSS.HS-LS3-3

A model of a DNA molecule is shown above.

The arrow indicates-

• the bond between adjacent phosphate and deoxyribose molecules

• the junction of introns and exons in the sense strand of DNA

• the hydrogen bond between complementary nucleotides

• the junction of a codon and a DNA triplet

Tags

NGSS.HS-LS1-1

A codon chart is shown

Which of these changes to the DNA triple 3’GCT 5’ will affect the protein produced?

• GTT

• TCT

• TCC

• GCA

Tags

NGSS.HS-LS1-1

NGSS.HS-LS1-6

NGSS.HS-LS3-2

Crossing-over between nonsister chromatids during meiosis is significant in heredity. This process most likely leads to an increase in which of the following?

• The expression of dominant traits

• Number of gametes

• The occurrence of polyploidy

• Genetic variation

Tags

NGSS.HS-LS3-2

Characteristics such as a widow’s peak or attached earlobes are determined by the genetic code. Which components of DNA are referred to as the genetic code?

• Phosphate groups

• Nitrogenous bases

• Deoxyribose sugars

• Hydrogen bonds

Tags

NGSS.HS-LS1-1

NGSS.HS-LS3-1

In cocker spaniels the allele for a black coat color (B) is dominant over the allele for a brown coat color (b). If a brown cocker spaniel is crossed with a heterozygous black cocker spaniel, which of the following genotypic ratios can be expected?

• 0 BB: 2 Bb: 2 bb

• 1 BB: 2 Bb: 1 bb

• 2 BB: 0 Bb: 2 bb

• 2 BB: 1 Bb: 0 bb

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

NGSS.HS-LS3-3