in the context of cholesterol levels ldl cholesterol is often referred to as

ATI TEAS 7

TEAS Test 7 science quizlet

1. In the context of cholesterol levels, LDL cholesterol is often referred to as:

A. HDL or "good" cholesterol.
B. LDL or "bad" cholesterol.
C. Total cholesterol, encompassing both LDL and HDL.
D. VLDL, a type of triglyceride transported in the bloodstream.

Correct answer: B

Rationale: LDL cholesterol is often referred to as "bad" cholesterol because high levels of LDL can lead to plaque buildup in the arteries, increasing the risk of heart disease and stroke. LDL cholesterol is considered harmful as it contributes to the formation of plaque in blood vessels, whereas HDL cholesterol helps remove LDL from the arteries. Choice A is incorrect because HDL is known as "good" cholesterol, which helps remove LDL cholesterol from the bloodstream. Choice C is incorrect as it refers to total cholesterol, which includes LDL, HDL, and other lipids. Choice D is incorrect as VLDL is a different type of lipoprotein that carries triglycerides and is not specifically related to LDL cholesterol.

2. Which of the following is an example of an aromatic hydrocarbon?

A. Ethane
B. Benzene
C. Propane
D. Butene

Correct answer: B

Rationale: Benzene is indeed an example of an aromatic hydrocarbon. Aromatic hydrocarbons are characterized by having a cyclic structure with alternating single and double bonds (pi bonds). Benzene fits this description, making it aromatic. On the other hand, ethane, propane, and butene are aliphatic hydrocarbons, which do not have the distinct cyclic structure of aromatic hydrocarbons. Ethane, propane, and butene are aliphatic hydrocarbons, which contain only single bonds and are not cyclic in nature. Therefore, they are not examples of aromatic hydrocarbons.

3. Which structure in the skin is responsible for producing oil that keeps the skin and hair moisturized?

A. Sudoriferous gland
B. Sebaceous gland
C. Hair follicle
D. Melanocyte

Correct answer: B

Rationale: The correct answer is B: Sebaceous gland. Sebaceous glands are responsible for producing oil (sebum) that keeps the skin and hair moisturized. Sudoriferous glands produce sweat, not oil, and are involved in temperature regulation. Hair follicles are responsible for hair growth and do not produce oil directly. Melanocytes are cells responsible for producing melanin, the pigment that gives skin its color, and are not involved in oil production.

4. What is the formula for calculating density?

A. Density = Volume / Mass
B. Density = Mass × Volume
C. Density = Mass / Volume
D. Density = Volume - Mass

Correct answer: A

Rationale: Density is defined as the amount of mass in a given volume. The formula for calculating density is Density = Mass / Volume. This means that you divide the mass of an object by its volume to determine its density. Therefore, the correct formula for calculating density is Density = Volume / Mass. Choice A is correct because density is calculated by dividing the volume by the mass. Choices B, C, and D are incorrect because they do not represent the correct relationship between mass and volume in calculating density.

5. Which of the following is a true statement about dominance in genetics?

A. All genes adhere to Mendel’s law of dominance.
B. A dominant allele will always be expressed.
C. When two dominant alleles are present, the resulting phenotype will express both traits.
D. There are three or more alleles possible for all genes.

Correct answer: B

Rationale: In genetics, dominance refers to the relationship between two different alleles of a gene where one allele (dominant) masks the expression of another allele (recessive) in an individual's phenotype. The correct statement about dominance is that a dominant allele will always be expressed in the phenotype, even in the presence of a recessive allele. This means that if an individual has at least one dominant allele for a particular trait, that trait will be expressed. Choice A is incorrect because not all genes follow Mendel’s law of dominance; exceptions do exist. Choice C is incorrect because when two dominant alleles are present, only one will be expressed due to complete dominance. Choice D is incorrect as there can be more than three alleles for a gene, and not all genes have three or more alleles.