Anatomy HESI A2 Practice Test

Correct Answer: B

Rationale: The correct answer is B: Energy production. Mitochondria are known as the powerhouse of the cell due to their role in producing energy in the form of ATP through cellular respiration. This process involves the breakdown of glucose to generate ATP, which is the main energy currency of the cell. Mitochondria have their own DNA and ribosomes, allowing them to produce some of their proteins, but they are not primarily responsible for protein synthesis (Choice A). Breaking down waste (Choice C) is mainly carried out by lysosomes. Cell division (Choice D) involves processes such as DNA replication and mitosis, which are not directly linked to the function of mitochondria.

Correct Answer: B

Rationale: White blood cells' main function is to fight infections. They are part of the immune system, detecting and destroying pathogens like bacteria and viruses. They do not carry oxygen (A), nutrients (C), or remove waste products (D). White blood cells play a crucial role in protecting the body from harmful invaders, making choice B the correct answer.

Correct Answer: A

Rationale: The correct answer is A: To filter blood and remove old red blood cells. The spleen is an important organ in the lymphatic system responsible for filtering blood, removing old or damaged red blood cells, and storing platelets. It also plays a role in immune function by producing antibodies and storing lymphocytes. Choices B, C, and D are incorrect as the spleen's main functions are related to blood filtration and immune response, not lymphocyte production, vitamin storage, or temperature regulation.

Correct Answer: B

Rationale: The correct answer is B: Ribosome. Ribosomes are responsible for protein synthesis as they are the cellular structures where translation of mRNA into proteins occurs. Ribosomes read the genetic code carried by mRNA and assemble amino acids into proteins. The other choices are incorrect because the nucleus houses the DNA and controls cell activities, the endoplasmic reticulum is involved in protein processing and transport, and the Golgi apparatus modifies and packages proteins for secretion. However, only ribosomes are directly responsible for protein synthesis.

Correct Answer: B

Rationale: The correct answer is B: Occipital lobe. The occipital lobe is primarily responsible for processing visual information. It contains the primary visual cortex, which receives and interprets visual stimuli from the eyes. This region processes shapes, colors, and motion. The temporal lobe (A) is involved in memory and auditory processing. The parietal lobe (C) is responsible for spatial awareness and sensory information integration. The frontal lobe (D) is associated with executive functions and motor skills. Thus, the occipital lobe is the correct choice for processing visual information.