Quiz - Transport systems Flashcards
Why do complex organisms like humans require a transport system?
a) They are multicellular.
b) Most of their cells are far from the external environment.
c) They need to move substances in and out of cells.
d) All of the above
d) All of the above
Explanation: Humans are complex organisms made of millions of cells, most of which are far from the outside environment and cannot directly get materials. Therefore, a transport system is needed for both taking substances to cells and carrying waste away.
Which of the following is NOT a primary function of a transport system in living things?
a) Taking substances to all cells.
b) Carrying waste substances away.
c) Producing energy for the organism.
d) Transporting oxygen and digested food.
c) Producing energy for the organism
Explanation: The transport system’s role is in delivering materials for energy production (like glucose and oxygen) and removing waste, but it does not directly produce energy itself.
What is the fundamental principle behind diffusion?
a) Movement of water molecules across a semi-permeable membrane.
b) Active transport of particles against a concentration gradient.
c) The net movement of particles from a region of higher concentration to a region of lower concentration.
d) The random motion of particles in a fluid.
c) The net movement of particles from a region of higher concentration to a region of lower concentration.
Explanation: Diffusion is defined as the movement of particles from an area of high concentration to an area of low concentration.
Diffusion always requires:
a) A partially permeable membrane.
b) A difference in concentration.
c) Energy input.
d) Movement of water molecules.
b) A difference in concentration.
Explanation: Diffusion occurs due to the random motion of particles and the tendency to spread out from areas of high concentration to low concentration. A membrane is not always required.
Which of the following is an example of diffusion occurring without a membrane?
a) Movement of mineral salts from soil to xylem.
b) Diffusion of oxygen from leaf to atmosphere.
c) Osmosis from dilute to concentrated solution.
d) Diffusion of water from soil to xylem.
b) Diffusion of oxygen from leaf to atmosphere.
Explanation: Diffusion of oxygen from the leaf to the atmosphere does not require a membrane. The diffusion of mineral salts and water requires a membrane.
Osmosis is best described as:
a) The movement of any particles across a partially permeable membrane.
b) A type of diffusion that only involves water molecules across a selectively permeable membrane.
c) The net movement of water molecules from a region of lower water potential to a region of higher water potential.
d) The movement of a concentrated solution to a dilute solution.
b) A type of diffusion that only involves water molecules across a selectively permeable membrane.
Explanation: Osmosis involves the movement of water molecules across a selectively permeable membrane, from a region of higher water potential to lower water potential.
Which of the following is NOT a component of the human circulatory system?
a) Heart.
b) Lungs.
c) Blood vessels.
d) Blood.
b) Lungs
Explanation: The lungs are part of the respiratory system and are involved in gas exchange, not the circulatory system. The circulatory system involves the heart, blood, and blood vessels.
The right side of the human heart primarily contains blood that is:
a) High in oxygen.
b) Low in oxygen.
c) Mixed with oxygen and carbon dioxide.
d) Traveling to the lungs.
b) Low in oxygen.
Explanation: The right side of the heart pumps deoxygenated blood to the lungs for oxygenation.
What is the function of the septum in the heart?
a) To pump blood around the body.
b) To control the heart rate.
c) To separate the left and right sides of the heart.
d) To transport oxygen to the heart muscles.
c) To separate the left and right sides of the heart.
Explanation: The septum divides the heart into two halves: the left side and the right side.
The walls of the heart are primarily made of:
a) Epithelial tissue.
b) Connective tissue.
c) Muscle tissue.
d) Nervous tissue.
c) Muscle tissue.
Explanation: The heart walls are made of cardiac muscle tissue, which contracts to pump blood.
What might result from a blockage in the coronary arteries?
a) High blood pressure.
b) A heart attack.
c) A stroke.
d) An increased heart rate.
b) A heart attack.
Explanation: Blockage in the coronary arteries reduces blood flow to the heart muscle, leading to a heart attack.
Which component of blood is responsible for transporting oxygen?
a) White blood cells.
b) Plasma.
c) Platelets.
d) Red blood cells.
d) Red blood cells.
Explanation: Red blood cells contain hemoglobin, which binds to oxygen and transports it throughout the body.
The biconcave shape of red blood cells is significant because it:
a) Allows them to squeeze through narrow capillaries.
b) Protects them from diseases.
c) Increases their surface area to volume ratio for efficient oxygen diffusion.
d) Makes them bright red in color.
c) Increases their surface area to volume ratio for efficient oxygen diffusion.
Explanation: The biconcave shape increases surface area, allowing more oxygen to be absorbed and released.
Which of the following blood components lacks a nucleus?
a) White blood cells.
b) Platelets.
c) Plasma.
d) Red blood cells.
d) Red blood cells.
Explanation: Red blood cells do not have a nucleus, maximizing space for hemoglobin.
What is the primary function of white blood cells?
a) Transporting nutrients.
b) Clotting blood.
c) Fighting diseases.
d) Transporting carbon dioxide.
c) Fighting diseases.
Explanation: White blood cells are part of the immune system and help fight infections.
Plasma is mainly composed of:
a) Red blood cells.
b) Water.
c) Hemoglobin.
d) Platelets.
b) Water.
Explanation: Plasma is made up of about 90% water, which carries nutrients, waste, and other substances in the blood.
Platelets are responsible for:
a) Transporting oxygen.
b) Fighting infections.
c) Playing a part in blood clotting.
d) Transporting nutrients and waste.
c) Playing a part in blood clotting.
Explanation: Platelets help in the clotting process to stop bleeding.
Arteries are characterized by having:
a) Thin, less muscular walls.
b) Valves to prevent backflow of blood.
c) Thick, muscular, and elastic walls to withstand high blood pressure.
d) Low blood pressure.
c) Thick, muscular, and elastic walls to withstand high blood pressure.
Explanation: Arteries carry blood at high pressure, which requires them to have thick, elastic walls.
Why do arteries have a narrow lumen compared to veins?
a) To allow red blood cells to move in single file.
b) To maintain high blood pressure.
c) To facilitate the exchange of substances with body cells.
d) To prevent backflow of blood.
b) To maintain high blood pressure.
Explanation: A narrow lumen helps to maintain the high pressure of blood being pumped from the heart.
Veins differ from arteries in that they:
a) Carry blood away from the heart.
b) Always carry oxygenated blood.
c) Have valves to prevent the backflow of blood, especially when going against gravity.
d) Have thicker walls to withstand high pressure.
c) Have valves to prevent the backflow of blood, especially when going against gravity.
Explanation: Veins have valves to ensure blood flows in one direction, particularly when it moves upwards against gravity.
Where does the exchange of substances between blood and body cells primarily occur?
a) Arteries.
b) Veins.
c) Capillaries.
d) Heart.
c) Capillaries.
Explanation: The capillaries’ thin walls allow for the exchange of gases, nutrients, and waste between blood and body cells.
The walls of capillaries are:
a) Thick and muscular.
b) Made up of multiple layers of cells.
c) Only a single layer of greatly flattened cells, facilitating exchange.
d) Similar in structure to arteries.
c) Only a single layer of greatly flattened cells, facilitating exchange.
Explanation: Capillaries have very thin walls to allow easy exchange of substances.
In capillaries, red blood cells move in single file to:
a) Increase blood pressure.
b) Speed up blood flow.
c) Slow down blood flow and increase the time for gas exchange.
d) Prevent damage to the capillary walls.
c) Slow down blood flow and increase the time for gas exchange.
Explanation: Moving in single file slows blood flow, allowing more time for the exchange of gases.
Which of the following structures are present in both plant roots and leaves?
a) Chloroplasts.
b) Stomata.
c) Xylem and phloem.
d) Root hairs.
c) Xylem and phloem.
Explanation: Both roots and leaves contain xylem and phloem for transporting water, minerals, and food.
The primary function of xylem is to transport:
a) Sugars from leaves to other parts of the plant.
b) Water and dissolved mineral salts from the roots to the rest of the plant.
c) Manufactured food through translocation.
d) Oxygen and carbon dioxide within the plant.
b) Water and dissolved mineral salts from the roots to the rest of the plant.
Explanation: Xylem is responsible for transporting water and minerals from the roots to other parts of the plant.
What substance provides mechanical support and strengthens the walls of xylem vessels?
a) Cellulose.
b) Pectin.
c) Lignin.
d) Suberin.
c) Lignin.
Explanation: Lignin is deposited in xylem walls, providing strength and structural support.
The transport of manufactured food in plants is called:
a) Transpiration.
b) Diffusion.
c) Osmosis.
d) Translocation.
d) Translocation.
Explanation: Translocation is the process of transporting manufactured food (mainly sugars) from the leaves to other parts of the plant.
Phloem transport primarily involves the movement of:
a) Water.
b) Sugars.
c) Oxygen.
d) Nutrients.
b) Sugars.
Explanation: Phloem is responsible for transporting the sugars produced in the leaves to other parts of the plant.
The direction of transport in phloem can vary, depending on the plant’s needs. This is known as:
a) Source to sink movement.
b) Osmosis.
c) Evapotranspiration.
d) Capillary action.
a) Source to sink movement.
Explanation: Phloem transport can move materials both up and down depending on the plant’s needs (from source to sink).
What is the primary factor that drives the flow of water in plants from roots to leaves?
a) Transpiration pull.
b) Capillary action.
c) Root pressure.
d) Active transport.
a) Transpiration pull.
Explanation: The main force that pulls water through plants is the transpiration pull created by the evaporation of water from leaves.
What is the necessity of a dedicated transport system in multicellular organisms like humans?
Multicellular organisms, such as humans, have complex structures with cells that are often far from the external environment. A transport system is essential to deliver substances to all cells and remove waste, ensuring all cells receive necessary resources for survival.
This system carries oxygen, digested food, and water while efficiently removing metabolic wastes.
What is the difference between diffusion and osmosis?
Diffusion is the net movement of particles from a region of higher concentration to a region of lower concentration, occurring with or without a membrane. Osmosis is a specific type of diffusion involving the net movement of water molecules through a partially permeable membrane from a region of higher water potential to lower water potential.
Examples include diffusion of ink in water and osmosis from soil to xylem.
What are the key structural features of arteries, veins, and capillaries?
- Arteries: Thick, muscular, and elastic walls with a narrow lumen to withstand high pressure and carry blood away from the heart.
- Veins: Thinner walls with less elasticity and valves to prevent backflow, carrying blood to the heart under lower pressure.
- Capillaries: Walls made of a single layer of flattened cells, allowing for effective exchange between blood and cells.
What does a ‘double circulatory system’ signify in humans?
A double circulatory system means blood passes through the heart twice in one complete circuit. It consists of the pulmonary circulation (blood to lungs for oxygenation) and systemic circulation (oxygenated blood to the body). This system allows for higher blood pressure in systemic circulation, improving oxygen delivery efficiency.
This is contrasted with a single circulatory system found in some organisms.
