TEAS 7 Science Practice Test

Correct Answer: D

Rationale: Peristalsis is the correct term as it refers to the rhythmic muscle contractions that propel food through the digestive tract. First, the circular muscles contract behind the food bolus, pushing it forward. Then, the longitudinal muscles contract, shortening the tract and pushing the food further. This process continues in a wave-like fashion, aiding in digestion. A: Digestion refers to the breakdown of food into smaller molecules. B: Deglutition is the process of swallowing food. C: Defecation is the elimination of waste from the body. Therefore, peristalsis is the correct term as it specifically describes the muscle contractions that move food through the digestive system.

Correct Answer: D

Rationale: The correct answer is D: neuromuscular junction. This is where nerve impulses travel to release neurotransmitters, such as acetylcholine, to stimulate muscle contraction. The sarcomere is the basic unit of muscle contraction, not the location of neurotransmitter release. Tendons connect muscles to bones and do not involve neurotransmitter release. The myelin sheath is a protective layer around nerves and is not directly involved in neurotransmitter release at the neuromuscular junction.

Correct Answer: C

Rationale: The correct answer is C: controlled experiment. In a controlled experiment, the researcher manipulates one or more independent variables to observe the effect on the dependent variable, while controlling for other variables. In this scenario, the researcher is controlling the conditions and variables to study the impact of the manipulated independent variable on the dependent variable. Incorrect choices: A: Field experiment involves conducting research in real-world settings, which may not necessarily involve manipulation of variables. B: Natural experiment involves observing naturally occurring events without any manipulation by the researcher. D: Observational study involves observing and recording data without any intervention or manipulation of variables.

Correct Answer: B

Rationale: The primary function of the respiratory system is to facilitate the exchange of oxygen and carbon dioxide in the body. Step 1: During inhalation, oxygen is taken into the lungs. Step 2: Oxygen is then transported to the cells via the bloodstream. Step 3: Carbon dioxide, a waste product, is removed from the body during exhalation. This process is essential for cellular respiration and energy production. Choices A, C, and D are incorrect because speech production, nutrient transport, and organ protection are not the primary functions of the respiratory system.

Correct Answer: B

Rationale: The correct answer is B: A dominant allele will always be expressed. This is because dominant alleles mask the expression of recessive alleles in heterozygous individuals. This means that if an individual carries at least one dominant allele for a particular trait, that dominant allele will be expressed phenotypically. In contrast, recessive alleles are only expressed when an individual is homozygous for that allele. Now, let's analyze the other choices: A: All genes adhere to Mendel's law of dominance - This is incorrect as not all genes follow Mendel's law of dominance, especially in cases of incomplete dominance or codominance. C: When two dominant alleles are present, the resulting phenotype will express both traits - This is incorrect as dominance determines which allele is expressed, so only the dominant trait will be expressed in this case. D: There are three or more alleles possible for all genes - This is incorrect as some genes may have multiple alleles, but not all genes have three