Practice TEAS Science Test

Correct Answer: B

Rationale: The primary function of white blood cells is to fight infection. They are key components of the immune system, identifying and attacking pathogens like bacteria and viruses. White blood cells produce antibodies to neutralize invaders. This function helps the body defend against illnesses and maintain overall health. Choices A, C, and D are incorrect because carrying oxygen (A) is primarily done by red blood cells, transporting nutrients (C) is mainly performed by blood plasma, and transporting waste (D) is mainly the role of the kidneys and liver.

Correct Answer: B

Rationale: Iron is the correct answer because it is an essential component of hemoglobin, the protein in red blood cells responsible for transporting oxygen throughout the body. Without iron, the body cannot produce enough hemoglobin, leading to anemia. Calcium, potassium, and sodium do not play a direct role in hemoglobin synthesis. Calcium is important for bone health, potassium is crucial for nerve and muscle function, and sodium helps regulate fluid balance. Iron is the only element among the choices that is directly involved in hemoglobin formation.

Correct Answer: D

Rationale: The correct answer is D: Pia mater. Pia mater is the innermost meningeal layer that is a thin membrane containing nerves and blood vessels. It directly covers the brain and spinal cord, supplying nourishment to the underlying cells. Arachnoid mater (A) is the middle meningeal layer that does not contain nerves and blood vessels. Dura mater (B) is the tough outermost layer that does not supply nourishment. Periosteum (C) is a connective tissue covering bones, not the meninges.

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.

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.