Practice TEAS Science Test

Correct Answer: D

Rationale: Platelets play a crucial role in clotting blood. When a blood vessel is damaged, platelets rush to the site to form a plug, preventing excessive bleeding. This process, known as hemostasis, involves platelets adhering to the damaged vessel wall, releasing chemicals to attract more platelets, and forming a clot to stop bleeding. Platelets do not transport oxygen (choice A), fight infection (choice B), or produce antibodies (choice C). Thus, the correct answer is D - Clot blood.

Correct Answer: D

Rationale: The correct answer is D: Recessive Inheritance. Mendelian inheritance follows the principles proposed by Gregor Mendel, where traits are determined by pairs of genes, with one being dominant and the other recessive. In recessive inheritance, an individual must inherit two copies of the recessive allele to exhibit the trait. This type of inheritance follows Mendel's laws of segregation and independent assortment. In contrast, incomplete dominance (A) shows blending of traits, polygenic alleles (B) involve multiple genes contributing to a single trait, and combination inheritance (C) is not a recognized term in Mendelian genetics.

Correct Answer: C

Rationale: The correct answer is C because an allergic reaction is triggered by the release of histamine and other inflammatory molecules from mast cells, which are stimulated by Immunoglobulin E. This process leads to symptoms such as hives, itching, swelling, and difficulty breathing. Other choices are incorrect because: A: While integumentary and respiratory systems are involved in allergic reactions, they are not overactive systems but rather respond to the allergen. B: B-cells produce antibodies, not immunoglobulins directly related to allergic reactions. D: Histamine is involved in allergic reactions, but keratin and collagen are not typically associated with allergic responses.

Correct Answer: B

Rationale: The correct answer is B: To absorb water and form feces. The large intestine mainly functions to absorb water from the indigestible food residue and solidify it into feces before excretion. This process helps in maintaining the body's fluid balance and preventing dehydration. Why the other choices are incorrect: A: The absorption of proteins primarily occurs in the small intestine, not the large intestine. C: Enzymes for digestion are produced in the pancreas and small intestine, not in the large intestine. D: Fat storage is mainly regulated by adipose tissue throughout the body, not the large intestine.

Correct Answer: B

Rationale: The correct answer is B: Lymph nodes. Lymph nodes are responsible for filtering lymph, which carries waste products and pathogens, supporting the immune system by trapping and destroying harmful substances. Lymph nodes contain immune cells that help fight infections. The other choices are incorrect because: A: Kidneys filter blood and regulate fluid balance. C: Pancreas produces digestive enzymes and insulin. D: Liver detoxifies harmful substances and processes nutrients.