Practice Science TEAS Test

Correct Answer: A

Rationale: The correct answer is A: Ribosome. Ribosomes are responsible for protein synthesis as they are the site where amino acids are assembled into proteins. They can be found in both the cytoplasm and attached to the endoplasmic reticulum. The other choices are incorrect because the nucleus houses the cell's genetic material, the mitochondrion is responsible for energy production, and the Golgi apparatus is involved in protein processing and packaging, not protein synthesis.

Correct Answer: B

Rationale: The correct answer is B: Melanocyte. Melanocytes are specialized cells in the skin that produce melanin, the pigment responsible for skin color. They are located in the epidermis and transfer melanin to nearby keratinocytes. Sudoriferous glands (A) produce sweat, sebaceous glands (C) produce sebum, and hair follicles (D) are responsible for hair growth. Therefore, they are not involved in melanin production in the skin.

Correct Answer: B

Rationale: The correct answer is B: Red blood cell. Red blood cells contain hemoglobin, a protein that binds to oxygen in the lungs and carries it to tissues throughout the body. White blood cells (A) are responsible for fighting infections, platelets (C) help with blood clotting, and plasma (D) is the liquid component of blood that carries nutrients and waste products. Thus, red blood cells are the only cells specifically designed to transport oxygen, making them the correct choice.

Correct Answer: B

Rationale: The correct answer is B: Hypothalamus. The hypothalamus regulates body temperature, hunger, and thirst through its control of the autonomic nervous system and hormonal systems. It plays a crucial role in maintaining homeostasis. The cerebellum (A) is responsible for coordination and balance, the thalamus (C) acts as a relay station for sensory information, and the medulla oblongata (D) regulates vital functions such as breathing and heart rate, but not body temperature, hunger, or thirst.

Correct Answer: A

Rationale: The correct answer is A. Macrophages are not found abundantly in the blood as they primarily reside in tissues. Neutrophils are the most abundant white blood cells in the blood. Choice B is correct as macrophages are indeed larger than neutrophils. Choice C is correct as macrophages are long-lived cells. Choice D is correct as monocytes are produced in the bone marrow and differentiate into macrophages once they migrate to tissues.