the process of bone formation and breakdown is called

ATI TEAS 7

TEAS 7 science practice questions

1. What is the term for the process of bone formation and breakdown?

A. Ossification
B. Resorption
C. Remodeling
D. All of the above

Correct answer: C

Rationale: The correct term for the process of bone formation and breakdown is remodeling. Ossification specifically refers to bone formation, while resorption pertains to bone breakdown. Remodeling encompasses both processes, as it involves the continuous cycle of bone formation and resorption to maintain bone strength and structure. Choice A, 'Ossification,' is incorrect as it only refers to bone formation. Choice B, 'Resorption,' is incorrect as it only refers to bone breakdown. Choice D, 'All of the above,' is incorrect as it includes terms that are not comprehensive of both bone formation and breakdown.

2. What is the difference between a homozygous recessive genotype and a homozygous dominant genotype?

A. Both have the same phenotype, but different genotypes.
B. Both have the same genotype, but different phenotypes.
C. Homozygous recessive has two dominant alleles, while homozygous dominant has two recessive alleles.
D. Homozygous recessive has two identical recessive alleles, while homozygous dominant has two identical dominant alleles.

Correct answer: D

Rationale: - Homozygous recessive genotype refers to an individual having two identical recessive alleles for a particular gene (e.g., rr for a trait where r represents the recessive allele). - Homozygous dominant genotype refers to an individual having two identical dominant alleles for a particular gene (e.g., RR for a trait where R represents the dominant allele). - The difference between the two genotypes lies in the specific alleles present in each case, with homozygous recessive having two recessive alleles and homozygous dominant having two dominant alleles. - This genetic difference results in different phenotypes being expressed, as the dominant allele typically masks the expression of the recessive allele in heterozygous individuals.

3. What is the term for a substance that can act as both a proton donor and a proton acceptor?

A. Acid
B. Base
C. Amphiprotic
D. Neutral

Correct answer: C

Rationale: Amphiprotic substances are those that can both donate and accept protons. They possess characteristics of both acids and bases, making them capable of acting as proton donors and proton acceptors. Choices A and B represent substances that are specific to either donating or accepting protons. Choice D does not describe a substance's ability to donate or accept protons since neutrality does not inherently involve proton donation or acceptance.

4. Which statement most accurately compares and contrasts the structures of DNA and RNA?

A. Both DNA and RNA have 4 nucleotide bases. Three of the bases are the same, but the fourth base is thymine in DNA and uracil in RNA.
B. Both DNA and RNA have the same 4 nucleotide bases. However, the nucleotides bond differently in DNA compared to RNA.
C. Both DNA and RNA have different numbers of nucleotide bases. DNA is a double helix while RNA is a single strand.
D. Both DNA and RNA have a double helix structure. However, DNA contains 6 nucleotide bases and RNA contains 4 nucleotide bases.

Correct answer: A

Rationale: The correct answer is A because DNA and RNA both consist of 4 nucleotide bases, namely adenine, cytosine, and guanine, which are common in both. The key difference lies in the fourth base, which is thymine in DNA and uracil in RNA. This distinction is fundamental in understanding the structural variances between DNA and RNA. Choice B is incorrect as it incorrectly states that the nucleotides bond differently in DNA compared to RNA without specifying the crucial base differences. Choice C is inaccurate as it misrepresents the numbers of nucleotide bases in DNA and RNA, and incorrectly describes DNA as a double helix and RNA as a single strand, which is not related to the difference in bases. Choice D is incorrect as it inaccurately portrays DNA with 6 nucleotide bases and RNA with 4, which is not true; both DNA and RNA have 4 nucleotide bases, but with differences in one of the bases.

5. What scientific term encompasses a permanent alteration in the DNA sequence?

A. Trait
B. Mutation
C. Allele
D. Variation

Correct answer: B

Rationale: A) Trait: A trait is a characteristic or feature of an organism that is determined by its genes. B) Mutation: A mutation is a permanent alteration in the DNA sequence that can result from errors during DNA replication, exposure to mutagens, or other factors. C) Allele: An allele is a variant form of a gene that can result in different traits or characteristics. D) Variation: Variation refers to the differences in traits or characteristics among individuals of the same species, which can be influenced by genetic and environmental factors. In this context, the term that specifically refers to a permanent alteration in the DNA sequence is "mutation."