the correct answer is d heterozygous traits contain one dominant and one recessive form of the gene which of the following is true of homozygous trait

HESI A2

Biology HESI A2 Practice Test

1. Which of the following is true of homozygous traits?

A. They are haploid
B. They are denoted AA
C. They are denoted aa
D. They are denoted Aa

Correct answer: B

Rationale: Homozygous traits have two identical forms of the gene, either both dominant (AA) or both recessive (aa). Therefore, choices B and C are true for homozygous traits. Choice A is incorrect because being haploid refers to having a single set of chromosomes, not necessarily homozygous traits. Choice D is incorrect as homozygous traits have identical alleles, so they are not denoted as Aa.

2. How many electron pairs are shared to form a double covalent bond?

A. 1
B. 2
C. 3
D. 4

Correct answer: B

Rationale: The correct answer is B. In a double covalent bond, two pairs of electrons are shared between two atoms. This sharing of two electron pairs results in a stronger bond compared to a single covalent bond where only one pair of electrons is shared. Choice A is incorrect because a single covalent bond involves the sharing of one pair of electrons. Choices C and D are incorrect as they do not represent the correct number of electron pairs shared in a double covalent bond.

3. What temperature in Fahrenheit is 50°C? (Enter numeric value only. If rounding is necessary, round to the nearest whole number.)

A. 110°F
B. 122°F
C. 130°F
D. 140°F

Correct answer: B

Rationale: To convert from Celsius to Fahrenheit, use the formula: F = (C × 9/5) + 32. Substituting 50°C: F = (50 × 9/5) + 32 = 122°F. Therefore, 50°C is approximately 122°F. Choices A, C, and D are incorrect because they do not reflect the accurate conversion of 50°C to Fahrenheit.

4. The student _____ for the final exam.

A. was preparing
B. was studying
C. had studied
D. is studying

Correct answer: B

Rationale: In the given sentence, the past continuous tense 'was studying' is the most appropriate choice to indicate an ongoing action in the past. 'Was preparing' (choice A) implies a completed action rather than an ongoing one. 'Had studied' (choice C) is past perfect tense, which is not suitable for indicating an ongoing action. 'Is studying' (choice D) is present continuous tense and does not fit the past context of the sentence.

5. What does it mean if a patient is lethargic?

A. Active
B. Exhausted
C. Confused
D. Restless

Correct answer: B

Rationale: Lethargic means feeling exhausted or sluggish. Being lethargic is the opposite of being active (choice A), confused (choice C), or restless (choice D). When a patient is lethargic, they lack energy and may appear tired or sluggish.