ATI TEAS 7 Science

Correct Answer: B

Rationale: The correct answer is B: Skeletal. Skeletal muscles are responsible for voluntary movements because they are attached to bones and are under conscious control. They enable us to move our body parts intentionally. Smooth muscles (A) are involuntary and found in internal organs. Cardiac muscles (C) are also involuntary and specific to the heart. Option D simply defines a term and is not a type of muscle.

Correct Answer: A

Rationale: The main function of lysosomes is to break down and recycle cellular waste through the process of autophagy. Lysosomes contain enzymes that break down various molecules, organelles, and pathogens. This process helps maintain cellular homeostasis and provides the cell with raw materials for new cell components. Storing carbohydrates (B) is incorrect as lysosomes do not function in this capacity. Synthesizing lipids (C) is incorrect as this is typically the role of the endoplasmic reticulum and Golgi apparatus. Transcribing DNA into mRNA (D) is incorrect as this process occurs in the nucleus by RNA polymerase.

Correct Answer: D

Rationale: The correct answer is D: Trachea. The trachea is the largest part of the airway. It is a tube that connects the larynx to the bronchi, allowing air to pass into and out of the lungs. The trachea is larger than the bronchi, bronchioles, and alveoli. Alveoli are tiny air sacs in the lungs where gas exchange occurs. Bronchi are the main air passages into the lungs, branching off from the trachea. Bronchioles are smaller branches of the bronchi. Therefore, the trachea is the largest structure among the given choices, making it the correct answer.

Correct Answer: B

Rationale: The correct answer is B: Cerebrospinal fluid. This is the protective fluid that surrounds the brain and spinal cord. It acts as a cushion, providing mechanical protection, and helps to maintain a stable environment for the central nervous system. Blood (A) does not directly surround the brain and spinal cord. Myelin sheath (C) is a protective covering of nerve fibers, not the fluid surrounding the brain and spinal cord. Insulin (D) is a hormone involved in regulating blood sugar levels and is not the fluid that protects the brain and spinal cord.

Correct Answer: C

Rationale: The correct answer is C: To regulate body functions through hormones. The endocrine system consists of glands that produce hormones to regulate various bodily functions like metabolism, growth, and reproduction. This system helps maintain homeostasis by communicating through chemical messengers. Choices A, B, and D are incorrect as fighting infection is primarily the role of the immune system, oxygen transportation is done by the respiratory system, and food breakdown is the function of the digestive system.