which of the following best describes phenotype

HESI RN

Biology Test

1. Which of the following best describes phenotype?

A. The hereditary potentials and limitations of an individual
B. The genetic makeup of an individual organism
C. The entire complex of genes inherited from both parents
D. All the observable characteristics of an organism

Correct answer: D

Rationale: The correct answer is D: 'All the observable characteristics of an organism.' Phenotype refers to all the observable characteristics of an organism, such as physical appearance, behavior, and other traits, which result from the interaction of its genotype with the environment. Choice A is incorrect because it describes genotype. Choice B is incorrect as it defines genotype, not phenotype. Choice C is incorrect as it refers to the genotype, the genetic information inherited from both parents, rather than the observable traits.

2. Water is a polar molecule that can be:

A. cohesive and corrosive
B. cohesive and adhesive
C. electrostatic and ionic
D. repellent and attractive

Correct answer: B

Rationale: Water is a polar molecule due to an uneven distribution of electrons, allowing it to form hydrogen bonds. This property makes water both cohesive (attracted to itself) and adhesive (attracted to other substances). Choice A is incorrect because water is not corrosive; rather, it is a solvent. Choices C and D are incorrect as they do not describe the cohesive and adhesive properties of water.

3. In the hierarchical organizational system, which of these is the most restrictive category?

A. Genus
B. Class
C. Kingdom
D. Species

Correct answer: D

Rationale: In the biological classification hierarchy, species is the most specific level, defining individual organisms that can interbreed. While genus, class, and kingdom are also categories in the hierarchy, they are broader and encompass a wider range of organisms compared to species. Genus groups together similar species, class groups similar orders, and kingdom is the broadest category grouping together similar phyla.

4. Which of the following correctly identifies the two types of cells?

A. Mitosis and meiosis
B. Mitochondrion and chloroplast
C. Genotype and phenotype
D. Prokaryotic and eukaryotic

Correct answer: D

Rationale: The correct answer is D: Prokaryotic and eukaryotic. Cells are classified into two major types: prokaryotic, which lack a nucleus, and eukaryotic, which have a defined nucleus and other membrane-bound organelles. Choice A, mitosis and meiosis, refers to cell division processes. Choice B, mitochondrion and chloroplast, are cell organelles involved in energy production and photosynthesis, respectively. Choice C, genotype and phenotype, relate to genetic characteristics and physical traits, not cell types.

5. Binary fission is a type of asexual reproduction. Which of the following occurs during the binary fission process?

A. The chromosomes bind to the plasma membrane
B. The chromosomes attach to the spindle formed along the axis
C. The chromosomes gather in the center of the cell
D. The chromosomes begin to separate

Correct answer: A

Rationale: The correct answer is A. In binary fission, the chromosomes bind to the plasma membrane before the cell splits into two. This initial step ensures that each daughter cell receives a complete set of genetic material. Choice B is incorrect because the spindle apparatus is characteristic of eukaryotic cell division (mitosis), not prokaryotic binary fission. Choice C is incorrect as chromosomes do not necessarily gather in the center of the cell during binary fission. Choice D is incorrect because the chromosomes do not begin to separate in binary fission; they replicate and then move to opposite ends of the cell before division.