What is the first step in pulmonary circulation?
- A. Blood moves toward the heart through the pulmonary veins.
- B. The pulmonary artery carries blood from the heart to the lungs.
- C. Carbon dioxide is exchanged for oxygen.
- D. Oxygenated blood moves through the aorta.
Correct Answer: B
Rationale: The correct answer is B: The pulmonary artery carries blood from the heart to the lungs. The first step in pulmonary circulation involves the right ventricle of the heart pumping deoxygenated blood into the pulmonary artery. The pulmonary artery then carries this deoxygenated blood from the heart to the lungs for oxygenation. This step is crucial for the exchange of carbon dioxide for oxygen to occur in the lungs, facilitating the oxygenation of blood. Choices A, C, and D are incorrect because they do not represent the initial step in pulmonary circulation. Option A refers to blood moving away from the heart, option C describes the gas exchange process that occurs in the lungs but not as the first step, and option D mentions oxygenated blood moving through the aorta, which happens after oxygenation in the lungs.
You may also like to solve these questions
How does the circulatory system work with the digestive system?
- A. The circulatory system removes undigested solids from the body.
- B. The circulatory system filters and collects digested materials.
- C. The circulatory system moves absorbed nutrients through the body.
- D. The circulatory system releases enzymes that control digestion.
Correct Answer: C
Rationale: The circulatory system works with the digestive system by transporting absorbed nutrients through the body. After digestion occurs in the digestive system, nutrients are absorbed into the bloodstream. The circulatory system then carries these nutrients to cells throughout the body where they are used for energy, growth, and repair. This process ensures that the necessary nutrients are delivered to where they are needed in the body. Choices A, B, and D are incorrect because the circulatory system is not responsible for removing undigested solids, filtering and collecting digested materials, or releasing enzymes that control digestion. These functions are primarily carried out by the digestive system.
The sebaceous glands are part of which system?
- A. Endocrine system
- B. Digestive system
- C. Respiratory system
- D. Integumentary system
Correct Answer: D
Rationale: The sebaceous glands are a component of the integumentary system, which includes the skin, hair, nails, and associated structures. Sebaceous glands are typically found throughout the skin and are responsible for producing an oily substance called sebum, which helps keep the skin and hair lubricated and moisturized. The endocrine system (Choice A) consists of glands that produce hormones, the digestive system (Choice B) is responsible for processing food, and the respiratory system (Choice C) is involved in breathing and gas exchange.
What structures are likely torn in a rotator cuff tear?
- A. Tendon and possibly ligament
- B. Muscle and possibly tendon
- C. Ligament and possibly muscle
- D. Tendon only
Correct Answer: A
Rationale: In a rotator cuff tear, the most common structures torn are the tendons of the rotator cuff muscles. In severe cases, the tear may also extend to involve the surrounding ligaments. Therefore, the correct answer is A, as it accurately represents the structures that are likely to be affected in a rotator cuff tear. Choice B is incorrect as muscles are not typically torn in a rotator cuff tear. Choice C is also incorrect as ligaments are not the primary structures involved in a rotator cuff tear. Choice D is incorrect because a rotator cuff tear typically involves more than just the tendons.
Which is a posterior feature of the human leg?
- A. Patella
- B. Quadriceps sartorius
- C. Triceps brachii
- D. Achilles tendon
Correct Answer: D
Rationale: The correct answer is the Achilles tendon. The Achilles tendon is a strong tendon located at the back of the human leg, connecting the calf muscles to the heel bone. This positioning makes it a posterior feature, situated at the rear of the leg. The patella, also known as the kneecap, is positioned at the front of the leg, making it an anterior feature. The quadriceps sartorius are muscles located in the front of the thigh, not at the back of the leg. Additionally, the triceps brachii is a muscle found in the upper arm, not in the leg, making it an incorrect choice.
Which hormone is produced by the pineal gland?
- A. Corticosteroid
- B. Oxytocin
- C. Prolactin
- D. Melatonin
Correct Answer: D
Rationale: Melatonin is the hormone produced by the pineal gland. It plays a crucial role in regulating the sleep-wake cycle and is instrumental in maintaining the body's circadian rhythm. Melatonin production is triggered by darkness and inhibited by light, aiding in signaling the body when it is time to sleep. Corticosteroid, oxytocin, and prolactin are hormones produced by other glands in the body and are not associated with the pineal gland. Therefore, they are incorrect choices for this question.