TEAS 7 Biology: Master Key Concepts

ATI TEAS 7

Biology

1. Differentiate between genotype and phenotype in the context of gene expression.

A. Genotype refers to the physical manifestation of a trait, while phenotype represents its underlying genetic makeup.
B. Genotype encompasses the spectrum of possible traits encoded by an organism's genes, while phenotype signifies the specific trait observed.
C. Genotype denotes the presence of dominant alleles, while phenotype reflects the influence of recessive alleles.
D. There is no distinction; both terms are interchangeable.

Correct answer: B

Rationale: Rationale: - Genotype refers to the genetic makeup of an organism, including all the genes and alleles it possesses. - Phenotype, on the other hand, refers to the observable physical characteristics or traits of an organism, which result from the interaction between its genotype and the environment. - While genotype represents the genetic potential or range of traits that an organism can express, phenotype reflects the actual expression of specific traits. - Therefore, option B correctly captures the distinction between genotype and phenotype in the context of gene expression.

2. What are enzymes?

A. Building blocks of muscle
B. Biological catalysts
C. Energy source
D. Antibodies

Correct answer: B

Rationale: Enzymes are proteins that speed up chemical reactions in our cells. They act like tiny factories, fitting specific molecules (substrates) into their active site to facilitate reactions.

3. A salt solution that conducts electricity well is most likely

A. A saturated solution
B. A concentrated solution of a strong electrolyte
C. A dilute solution of a weak acid
D. A mixture of a neutral compound and water

Correct answer: B

Rationale: The correct answer is B: "A concentrated solution of a strong electrolyte." Strong electrolytes completely dissociate into ions in solution, thereby increasing the conductivity of the solution. Concentrated solutions have a higher amount of dissolved solute particles, which leads to more ions available for conducting electricity. In contrast, saturated solutions may contain undissolved solute, limiting the number of ions in solution. Dilute solutions have fewer ions and weak acids only partially dissociate, reducing conductivity. A neutral compound and water do not provide ions for conducting electricity. Therefore, a concentrated solution of a strong electrolyte is most likely to conduct electricity well due to the high concentration of ions present.

4. Which phenomenon explains the formation of rainbows in the sky?

A. Diffraction
B. Interference
C. Refraction and dispersion of sunlight by water droplets.
D. Reflection from clouds

Correct answer: C

Rationale: Refraction and dispersion of sunlight by water droplets in the atmosphere separate white light into its constituent colors, creating the rainbow phenomenon.

5. What is the main function of peroxisomes in the cell?

A. To break down hydrogen peroxide
B. To synthesize lipids and other cellular components
C. To package and transport proteins
D. To store genetic material

Correct answer: A

Rationale: Rationale: Peroxisomes are membrane-bound organelles found in eukaryotic cells that contain enzymes involved in various metabolic processes. One of the main functions of peroxisomes is to break down hydrogen peroxide, a toxic byproduct of metabolism, into water and oxygen through the action of the enzyme catalase. This process helps protect the cell from oxidative damage caused by hydrogen peroxide. While peroxisomes are involved in other metabolic functions such as lipid metabolism and the synthesis of bile acids, their primary role is the breakdown of hydrogen peroxide.