Which statement correctly matches the valve with its function in the heart?
- A. The aortic valve allows oxygenated blood to flow from the left ventricle to the rest of the body.
- B. The mitral valve opens to allow blood flow from the left atrium to the left ventricle.
- C. The pulmonic valve allows deoxygenated blood to flow from the right ventricle to the pulmonary artery.
- D. The tricuspid valve allows deoxygenated blood to flow from the right atrium to the right ventricle.
Correct Answer: A
Rationale: The correct answer is A. The aortic valve allows oxygenated blood to flow from the left ventricle to the rest of the body. When the left ventricle contracts, the aortic valve opens to allow blood to be pumped into the aorta, the body's main artery that carries oxygen-rich blood to various parts of the body. Choices B, C, and D are incorrect because they do not match the described functions of the mitral, pulmonic, and tricuspid valves, respectively. The mitral valve controls the flow of blood between the left atrium and left ventricle, the pulmonic valve regulates the flow of blood from the right ventricle to the pulmonary artery, and the tricuspid valve manages the blood flow between the right atrium and right ventricle.
You may also like to solve these questions
In an oxidation reaction,
- A. an oxidizing agent gains electrons.
- B. an oxidizing agent loses electrons.
- C. a reducing agent gains electrons.
- D. a reducing agent loses electrons.
Correct Answer: B
Rationale: In an oxidation reaction, the substance being oxidized loses electrons, not gains them. An oxidizing agent is responsible for causing oxidation in another substance by accepting electrons, hence it undergoes reduction and loses electrons. Therefore, the correct statement is 'an oxidizing agent loses electrons,' making choice B the correct answer. Choices A, C, and D are incorrect because in an oxidation reaction, the oxidizing agent does not gain electrons, a reducing agent does not gain electrons, and a reducing agent does not lose electrons.
When a patient is lying flat on their back, which of the following positions are they in?
- A. Prone.
- B. Supine.
- C. Lateral.
- D. Medial.
Correct Answer: B
Rationale: When a patient is lying flat on their back, they are in the supine position. In the supine position, the person's face is facing upward, and their back is touching the surface they are lying on. This position is commonly used for medical examinations and procedures. Choice A, 'Prone,' refers to lying face down, not on the back. Choice C, 'Lateral,' indicates lying on the side. Choice D, 'Medial,' pertains to the middle or center, not a position in relation to lying on the back.
Which of these body parts does not contain melanin?
- A. Hair
- B. Nails
- C. Skin
- D. Iris
Correct Answer: D
Rationale: The iris is the colored part of the eye that determines the eye's color. Melanin is not present in the iris, unlike hair, nails, and skin. Melanin gives color to hair, nails, and skin, but not to the iris. Therefore, the correct answer is the iris (Choice D). Choices A, B, and C contain melanin and are incorrect.
What initiates the process of coagulation?
- A. When blood changes from a gel to liquid form.
- B. Begins instantly after a blood vessel has been damaged.
- C. A simple single-phase response of the blood drying upon contact with the air.
- D. Also known as clotting, or the formation of fibrin.
Correct Answer: B
Rationale: The correct answer is B. The process of coagulation, also known as blood clotting, begins instantly after a blood vessel has been damaged. When a blood vessel is injured, the body quickly responds by initiating a cascade of reactions to form a blood clot, which helps to stop bleeding and promote healing. Choices A, C, and D are incorrect because coagulation does not occur just when blood changes from a gel to liquid form, it is not a response of blood drying upon contact with air, and it is not simply the formation of fibrin. The primary trigger for coagulation is vascular injury.
What are groups of cells that perform the same function called?
- A. tissues
- B. plastids
- C. organs
- D. molecules
Correct Answer: A
Rationale: Groups of cells that perform the same function are called tissues. Tissues are composed of a group of similar cells working together to carry out specific functions within an organism. Each type of tissue has a specialized structure that enables it to perform its specific role effectively. Plastids are cell organelles found in plants responsible for functions like photosynthesis and storage, not groups of cells. Organs are composed of different types of tissues working together. Molecules are made up of atoms and are not groups of cells.