which structure in the eye focuses light onto the retina

HESI A2

HESI A2 Anatomy and Physiology Quizlet

1. Which structure in the eye focuses light onto the retina?

A. Cornea
B. Lens
C. Pupil
D. Iris

Correct answer: B

Rationale: The lens of the eye is responsible for focusing light onto the retina. It plays a crucial role in adjusting the focus to allow for clear vision. After the light passes through the lens, it reaches the retina where it is converted into neural signals for the brain to interpret. The cornea is the transparent outer layer of the eye that helps in focusing light, but its main function is to protect the eye. The pupil is the opening in the center of the iris that regulates the amount of light entering the eye. The iris is the colored part of the eye that controls the size of the pupil.

2. How many bones are in the human foot?

A. 6
B. 16
C. 26
D. 36

Correct answer: C

Rationale: The correct answer is C: 26. The human foot consists of 26 bones, including tarsal bones, metatarsal bones, and phalanges. These bones collaborate to offer support, flexibility, and stability for various activities like standing, walking, and running. Choice A (6) is incorrect as it is too low for the number of bones in the human foot. Choice B (16) is incorrect as it underestimates the actual number of bones in the foot. Choice D (36) is incorrect as it overestimates the number of bones in the human foot.

3. Which fibrous connective tissue attaches muscles to bones?

A. Tendons
B. Ligaments
C. Cartilage
D. Fascia

Correct answer: A

Rationale: Tendons are fibrous connective tissues that attach muscles to bones, allowing the transmission of forces generated by muscles and facilitating movement at joints. Ligaments, on the other hand, connect bones to other bones, providing stability. Cartilage is a firm, flexible connective tissue found in joints and the respiratory tract. Fascia surrounds muscles, groups of muscles, blood vessels, and nerves, offering support and protection. Therefore, the correct answer is tendons as they specifically connect muscles to bones.

4. What is a primary function of the skeletal system?

A. Production of red blood cells
B. Support and protection
C. Secretion of hormones
D. Regulation of body temperature

Correct answer: B

Rationale: The correct answer is B: Support and protection. The primary functions of the skeletal system include providing structural support to the body and protecting internal organs. While the skeletal system also plays a role in hematopoiesis (production of blood cells) and stores minerals, its main function is to support the body's framework and protect vital organs. Choices A, C, and D are incorrect as they do not directly relate to the primary functions of the skeletal system.

5. Which gland is often referred to as the 'master gland'?

A. Thyroid gland
B. Pituitary gland
C. Adrenal gland
D. Pineal gland

Correct answer: B

Rationale: The pituitary gland is often referred to as the 'master gland' because it controls the release of hormones from other endocrine glands in the body. It secretes a variety of hormones that regulate various bodily functions and play a crucial role in maintaining homeostasis. The thyroid gland (Choice A) plays a role in regulating metabolism, the adrenal gland (Choice C) secretes hormones involved in stress response, and the pineal gland (Choice D) produces melatonin to regulate sleep-wake cycles, but they are not known as the 'master gland' due to their functions.