Nokea
What is the main function of the lungs?
- A. To transport oxygen and nutrients throughout the body
- B. To coordinate movement and sensory information
- C. To filter waste products from the blood
- D. To exchange oxygen and carbon dioxide between the body and the environment
Correct Answer: D
Rationale: The main function of the lungs is to exchange oxygen and carbon dioxide between the body and the environment. This process occurs through the alveoli in the lungs where oxygen from inhaled air enters the bloodstream, and carbon dioxide is removed from the bloodstream and exhaled. Option A is incorrect as the transportation of oxygen and nutrients throughout the body is primarily carried out by the circulatory system, not the lungs. Option B is incorrect as coordinating movement and sensory information is a function of the nervous system, not the lungs. Option C is incorrect as filtering waste products from the blood is primarily the role of the kidneys, not the lungs. Therefore, the correct answer is D.
You may also like to solve these questions
Iron is a transition metal, which means it often forms a cation with a charge of what?
- A. 2- or 3-
- B. 1-
- C. 2+ or 3+
- D. 1+
Correct Answer: C
Rationale: The correct answer is C: 2+ or 3+. Transition metals, like iron, are known for their ability to exhibit variable oxidation states. This characteristic allows them to form cations with charges such as 2+ or 3+. Specifically, iron can form cations with these charges due to the varying electron configurations in its d-orbitals. The other choices are incorrect because transition metals typically form positively charged cations, not negatively charged ones. Additionally, while iron can form cations with charges of 2+ or 3+, it does not commonly form cations with charges of 1- or 1+. Transition metal cations play a crucial role in forming coordination complexes with ligands, highlighting their importance in various chemical reactions.
What is the term for a solution that has exactly the same concentration of solute as another solution?
- A. Saturated solution
- B. Unsaturated solution
- C. Isotonic solution
- D. Concentrated solution
Correct Answer: C
Rationale: An isotonic solution is a solution that has the same concentration of solute as another solution. When cells are placed in an isotonic solution, there is no net movement of water across the cell membrane, maintaining equilibrium. Choice A, a saturated solution, refers to a solution that contains the maximum amount of solute that can be dissolved at a given temperature. Choice B, an unsaturated solution, is a solution that contains less solute than a saturated solution under the same conditions. Choice D, a concentrated solution, is a solution with a high amount of solute compared to the solvent.
What is the definition of 'acceleration' in terms of motion?
- A. Change in velocity over time
- B. Speed in a straight line
- C. Distance covered in a given time
- D. Force applied to an object
Correct Answer: A
Rationale: Acceleration is defined as the rate of change of velocity of an object over time. It represents how an object's velocity is changing, either by speeding up, slowing down, or changing direction. Option B, 'Speed in a straight line,' actually refers to velocity, not acceleration. Option C, 'Distance covered in a given time,' is more related to speed, as it measures how much ground is covered in a specific time period. Option D, 'Force applied to an object,' is not the definition of acceleration; it is a force exerted on an object that can cause acceleration.
What is the primary function of red blood cells?
- A. To transport nutrients
- B. To transport oxygen
- C. To fight infection
- D. To produce antibodies
Correct Answer: B
Rationale: The correct answer is B: To transport oxygen. Red blood cells play a crucial role in carrying oxygen from the lungs to all the tissues and organs in the body. This oxygen transport is essential for cellular respiration, where oxygen is used in the production of energy. Red blood cells do not primarily transport nutrients, fight infection, or produce antibodies. Choice A is incorrect because while red blood cells do carry some nutrients, their primary function is to transport oxygen. Choice C is incorrect because immune cells, not red blood cells, are responsible for fighting infections. Choice D is incorrect as antibody production is mainly carried out by specialized white blood cells, not red blood cells.
In the process of osmosis, the solvent moves from an area of...
- A. Low solute concentration to high solute concentration
- B. Hotter solution to colder solution
- C. Colder solution to hotter solution
- D. High solute concentration to low solute concentration
Correct Answer: D
Rationale: In the process of osmosis, solvent molecules move from an area of high solute concentration to low solute concentration. This movement occurs to equalize the solute concentrations on both sides of the semi-permeable membrane. As water tends to move towards higher solute concentrations, the solvent moves in this direction to balance the concentrations and establish equilibrium. Choices A, B, and C are incorrect because osmosis involves the movement of solvent, not solute, and it moves towards the area of higher solute concentration, not lower. Therefore, the correct answer is option D.