the order of the hierarchy of levels in the biological classification of organisms is

HESI A2

HESI A2 Biology Practice Test

1. What is the correct order of the hierarchy of levels in the biological classification of organisms?

A. Kingdom, phylum, class, order, family, genus, and species
B. Phylum, kingdom, class, order, family, genus, and species
C. Order, phylum, class, kingdom, family, genus, and species
D. Kingdom, phylum, order, class, family, genus, and species

Correct answer: A

Rationale: The correct order of the hierarchy of levels in the biological classification of organisms is Kingdom, Phylum, Class, Order, Family, Genus, and Species. This order is based on the Linnaean system of classification, with each level representing a progressively more specific grouping of organisms. Choice B is incorrect because it starts with Phylum instead of Kingdom. Choice C is incorrect as it places Order before Phylum. Choice D is incorrect because it does not follow the correct order of the biological classification hierarchy.

2. What are the two catabolic pathways that lead to cellular energy production?

A. Fermentation and internal respiration
B. Fermentation and external respiration
C. Fermentation and cellular respiration
D. Fermentation and anaerobic respiration

Correct answer: C

Rationale: The correct answer is 'Fermentation and cellular respiration.' Fermentation is an anaerobic catabolic process that occurs in the absence of oxygen, producing limited amounts of ATP. Cellular respiration, on the other hand, is the aerobic catabolic pathway that occurs in the presence of oxygen and is the most efficient way of producing ATP. Choices A, B, and D are incorrect because internal respiration, external respiration, and anaerobic respiration are not the correct pathways leading to cellular energy production.

3. Which is true of the term Phenotype?

A. It is the genetic code
B. Phenotype determines genotype
C. Genotype determines phenotype
D. Genotype, epigenetic factors, and environmental factors determine phenotype

Correct answer: D

Rationale: The term "phenotype" refers to the observable characteristics or traits of an organism, which are determined by a combination of genotype (genetic makeup), epigenetic factors (modifications to gene expression), and environmental factors (external influences and experiences). Genotype, epigenetic factors, and environmental factors all play a role in determining an individual's phenotype, making option D the correct statement. Options A, B, and C are incorrect because the phenotype is not the genetic code, the phenotype does not determine the genotype, and it is the genotype that influences the phenotype, not the other way around.

4. Select the strand of DNA that would match this segment: ACTTGCA

A. TGAACGT
B. GACCATG
C. ACTTGCA
D. None of the above

Correct answer: A

Rationale: The correct match for the DNA segment ACTTGCA is TGAACGT. In DNA, adenine (A) always pairs with thymine (T), and cytosine (C) always pairs with guanine (G). Therefore, the complementary strand to ACTTGCA should be TGAACGT, making choice A the correct answer. Choice B (GACCATG) does not follow the base pairing rules; hence, it is incorrect. Choice C (ACTTGCA) is the original segment, not its complementary strand. Choice D is incorrect as well because a matching strand does exist.

5. The cell membrane consists of a bilayer of phospholipids with proteins, cholesterol, and glycoproteins. What does this bilayer create?

A. Impermeable
B. Permeable
C. Selectively permeable
D. Selectively impermeable

Correct answer: C

Rationale: The correct answer is 'Selectively permeable.' The cell membrane's bilayer structure allows it to be selectively permeable, meaning it can control the passage of substances. This property enables the membrane to regulate the entry and exit of specific molecules, ions, and other substances. Choice A, 'Impermeable,' is incorrect as the cell membrane is not completely impermeable and does allow certain substances to pass through. Choice B, 'Permeable,' is also incorrect as it does not address the selective nature of the membrane. Choice D, 'Selectively impermeable,' is a contradictory term and does not accurately describe the cell membrane's function.