1.
Which element is NOT one of the three most common ones in a plant?
Correct Answer
B. Sulfur
Explanation
Sulfur is not one of the three most common elements in a plant. The three most common elements in a plant are oxygen, carbon, and hydrogen. These elements are essential for photosynthesis and the formation of organic compounds in plants. Sulfur, although important for plant growth and development, is not as abundant as the other three elements in plants.
2.
The plasma membrane of plant cells
Correct Answer
C. Actively transports some mineral ions into the cell.
Explanation
The plasma membrane of plant cells actively transports some mineral ions into the cell. This is because plants need certain minerals, such as potassium and magnesium, for various cellular processes and growth. The plasma membrane contains specific transport proteins that actively move these mineral ions from areas of lower concentration outside the cell to areas of higher concentration inside the cell. This selective transport allows plants to regulate the uptake of minerals and maintain proper cellular function.
3.
An epiphyte is a plant that
Correct Answer
B. Does not have roots but absorbs nutrients from the air.
Explanation
An epiphyte is a plant that does not have roots but absorbs nutrients from the air. Epiphytes are able to obtain nutrients and water from the atmosphere through specialized structures such as trichomes or scales on their leaves. They do not rely on roots to extract nutrients from the soil like other plants. Instead, they attach themselves to other plants or structures for support, using them as a substrate. This adaptation allows epiphytes to thrive in environments where soil conditions may be unfavorable or limited, such as in tree canopies or on rocks.
4.
Which of these is most likely to be produced by the plant in usable amounts?
Correct Answer
C. Oxygen
Explanation
Plants are known to produce oxygen through the process of photosynthesis. During photosynthesis, plants use sunlight, water, and carbon dioxide to produce glucose and release oxygen as a byproduct. Oxygen is essential for various biological processes and is used by both plants and animals for respiration. Therefore, it is most likely that the plant will produce oxygen in usable amounts.
5.
Which term describes forcing water out of the plant at the edges of its leaves?
Correct Answer
D. Guttation
Explanation
Guttation is the term that describes the process of forcing water out of the plant at the edges of its leaves. This occurs when excess water pressure builds up in the plant, causing water to be released through specialized structures called hydathodes. Guttation typically happens during periods of high humidity and can be observed as droplets of water forming on the edges of leaves. It is different from transpiration, which is the process of water loss from the plant through the stomata on the leaf surface. Root pressure and atmospheric pressure are not directly related to the specific process described.
6.
Which force pushes water into the xylem as osmosis moves water into the root?
Correct Answer
C. Root pressure
Explanation
Root pressure is the force that pushes water into the xylem as osmosis moves water into the root. This pressure is generated by the active transport of minerals into the root cells, which creates a higher solute concentration in the root compared to the surrounding soil. This causes water to move into the root through osmosis, creating a positive pressure that pushes the water up the xylem vessels. Root pressure is especially important in young plants or during periods of high water availability.
7.
Which statement is NOT true about stomates?
Correct Answer
D. Guard cells surrounding stomates lack chloroplasts that other epidermal cells contain.
Explanation
Guard cells surrounding stomates lack chloroplasts that other epidermal cells contain. Stomates are small openings on the surface of leaves that allow for gas exchange. Guard cells, which surround the stomates, control the opening and closing of the stomates. When the guard cells become turgid, they swell and the stomates open, allowing for the exchange of gases. However, unlike other epidermal cells, guard cells lack chloroplasts, which are responsible for photosynthesis. This is because the primary function of guard cells is to regulate gas exchange, rather than produce energy through photosynthesis.
8.
The main component of phloem is
Correct Answer
C. Sucrose.
Explanation
Sucrose is the correct answer because it is the main component of phloem. Phloem is responsible for transporting sugars, mainly in the form of sucrose, from the leaves to other parts of the plant. This transportation allows the plant to distribute nutrients and energy to where it is needed for growth and development. Hormones, amino acids, glucose, and lipids are not the main components of phloem and do not play a primary role in its function.
9.
A stomate allows carbon dioxide into the leaf and water out of the leaf.
Correct Answer
A. True
Explanation
Stomates are small openings found on the surface of leaves that regulate the exchange of gases and water vapor. They allow carbon dioxide to enter the leaf for photosynthesis, which is essential for the plant's growth. Additionally, stomates also facilitate the release of excess water vapor through transpiration, preventing the leaf from becoming waterlogged. Therefore, the statement that stomates allow carbon dioxide into the leaf and water out of the leaf is true.