HESI A2
HESI A2 Version 1 Anatomy and Physiology Questions
Question 1 of 5
Which structure of the nervous system carries action potentials in the direction of a synapse?
Correct Answer: B
Rationale: The correct answer is the axon. The axon is a long, slender projection of a neuron that carries nerve impulses away from the cell body towards other neurons, muscles, or glands. Action potentials travel along the axon to the axon terminals where they lead to the release of neurotransmitters at the synapse, allowing communication with other neurons or target cells. The cell body contains the nucleus and organelles of the neuron but does not transmit action potentials. Neurons are the functional unit of the nervous system composed of the cell body, dendrites, and axon. Myelin is a fatty substance that surrounds and insulates axons, helping to speed up the transmission of nerve impulses but does not carry action potentials towards the synapse.
Question 2 of 5
What force primarily drives filtration in the kidneys?
Correct Answer: D
Rationale: Filtration in the kidneys is primarily driven by blood pressure. The glomerulus filters blood under pressure, allowing small molecules and fluids to pass through into the renal tubules while retaining larger molecules like proteins. Osmosis, smooth muscle contraction, and peristalsis do play roles in kidney function, but blood pressure is the main force responsible for the initial filtration process.
Question 3 of 5
Which of the following epithelial types is correctly matched with its major function?
Correct Answer: D
Rationale: The correct answer is D - Simple columnar epitheliumā€"secretion or absorption. Simple columnar epithelium is typically found in areas where secretion or absorption is the primary function, such as the lining of the intestines. This type of epithelium is composed of a single layer of tall, narrow cells that are well suited for these functions. Simple squamous epithelium is more associated with diffusion due to its thin structure allowing for easy movement of molecules through it. Stratified squamous epithelium is designed to protect underlying tissues and is not primarily involved in diffusion.
Question 4 of 5
What percentage of a female's blood volume is composed of red blood cells?
Correct Answer: C
Rationale: Approximately 40% of a female's blood volume is composed of red blood cells, a proportion known as hematocrit. This percentage may vary slightly based on factors like age and overall health. Red blood cells play a crucial role in oxygen transport throughout the body, and deviations from the normal range can indicate various medical conditions.
Question 5 of 5
During digestion, what does the stomach muscle churn and mix food into, turning it into a soupy substance known as which of the following?
Correct Answer: C
Rationale: The correct answer is C: Chyme. During digestion, the stomach muscle contracts and mixes food with digestive juices, breaking it down into a thick, soupy liquid called chyme. This chyme is then slowly released into the small intestine for further digestion and absorption of nutrients.