Checkpoint 6 Quiz

The arctic fox inhabits northern areas of North America. The same arctic fox is shown in the drawing at different times of the year. What causes this change in fur color?

• The alleles for fur color change as the arctic fox grows older.

• Gene expression for fur color is regulated by latitude.

• The arctic fox has two traits for fur color that are determined at birth.

• Gene expression for fur color is regulated by temperature.

A diagram of the steps in the production of a protein is shown. Which description identifies the purpose of Step A in this process?

• To correct mutations in the DNA sequence

• To produce an exact copy of the DNA molecules

• To copy the DNA of a gene sequence onto a strand of mRNA

• To assist in the folding of a protein

The diagram shows a process that occurs during the development of an organism. Which statement explains how the different cell types in the image formed?

• Each cell type uses its own unique replication process.

• Each cell type expresses different genes at different times.

• Each cell type contains a different part of the original DNA.

• Each cell type has different enzymes to replicate genetic material.

A genetic cross involving two unlinked genes is represented: AaGg x aaGg. Which genotype is NOT possible in the offspring produced by the cross?

• AAGG

• Aagg

• aaGg

• aaGG

Some angelfish colors are determined by codominance. Possible phenotypes and genotypes of angelfish colors are shown. Which answer shows the expected phenotypes of offspring resulting from a cross between a black angelfish and a black-lace angelfish?

• Phenotypic probability of offspring - Silver (–), Black (50%), Black Lace (50%)

• Phenotypic probability of offspring - Silver (50%), Black (50%), Black Lace (–)

• Phenotypic probability of offspring - Silver (25%), Black (25%), Black Lace (50%)

• Phenotypic probability of offspring - Silver (25%), Black (50%), Black Lace (25%)

There are approximately 113 species and subspecies of snakes in Texas. Why would it be important for scientists to use a standardized taxonomic system when naming each species of snake?

• To ensure that all species of snakes are located in the fossil record

• To avoid confusion in the identification of a variety of snake species

• To place snakes in various groups based on their habitats in the ecosystem

• To determine the impact of removing one species of snake from their habitat in the ecosystem

Which insects are MOST CLOSELY related? Select TWO correct answers.

• Trigonopterus delta

• Carabus granulatus

• Agra nevadana

• Agra vetteri

A dichotomous key of different mollusks is shown. Which mollusk moves by jet propulsion and does not have an external shell?

• Squid

• Slug

• Nautilus

• Snail

Which characteristic do all organisms in Kingdoms Animalia, Protista, and Fungi have in common?

• They are eukaryotic.

• They are prokaryotic.

• They are unicellular.

• They are multicellular.

After a wheat field is cleared, wild grasses and weeds begin growing. This process is considered —

• primary succession because pioneer species appear

• primary succession because there are no large trees

• secondary succession because soil is already present

• secondary succession because the field contains inorganic matter