Practice Science TEAS Test

Correct Answer: B

Rationale: The correct answer is B: Gene. A gene is a smaller unit of genetic information than a chromosome. Chromosomes contain many genes, so they are larger in scale. The genome (option A) refers to the complete set of an organism's genetic material, which includes all the chromosomes. DNA (option C) is the genetic material that makes up chromosomes and genes. Option D is incorrect because while all the listed choices are related to genetics, genes are specifically smaller than chromosomes.

Correct Answer: D

Rationale: The correct answer is D because the liver filters and detoxifies digestion byproducts. It processes nutrients from food, removes toxins, and metabolizes drugs. Choice A is incorrect because the liver produces bile, not just for digestion but also for waste elimination. Choice B is incorrect as the gallbladder stores bile. Choice C is incorrect as the liver converts waste ammonia into urea as part of the metabolic process, not specifically related to digestion.

Correct Answer: A

Rationale: The correct answer is A: B6. Vitamin B6, also known as pyridoxine, is not synthesized in the large intestine. It is primarily absorbed in the small intestine. Biotin, Pantothenic acid, and Vitamin K are all synthesized in the large intestine. Biotin and Pantothenic acid are produced by gut bacteria, while Vitamin K is synthesized by the intestinal flora. Therefore, the correct answer is A because B6 is not synthesized in the large intestine, unlike the other options.

Correct Answer: D

Rationale: The independent variable is the factor that the researcher manipulates or controls. In this experiment, the independent variable is the dog food type as it is being purposely changed to observe its effect on the dependent variable. Time is not manipulated, dog weight and species are not changed intentionally, making them unsuitable as independent variables. The correct answer is D because it is the variable that is being tested and controlled in the experiment.

Correct Answer: B

Rationale: The correct answer is B: Retina. The retina is a layer of light-sensitive cells located at the back of the eye that detects light and converts it into signals for the brain through the optic nerve. The iris (A) controls the amount of light entering the eye, the lens (C) helps to focus light onto the retina, and the pupil (D) regulates the amount of light entering the eye, but they do not convert light into signals for the brain like the retina does.