1.
Increases in stem length occur at
Correct Answer
D. Apical meristem.
Explanation
The correct answer is apical meristem. The apical meristem is responsible for the growth in length of the stem. It is located at the tip of the stem and produces new cells that differentiate into various types of tissues, allowing the stem to elongate. The vascular cambium and cork cambium are responsible for the growth in thickness of the stem, producing secondary tissues. The lateral meristem is another term for the vascular cambium, so it is not the correct answer in this context.
2.
Parenchyma cells are specialized for and involved in all of the following activities EXCEPT
Correct Answer
C. Conduction of food.
Explanation
Parenchyma cells are specialized for and involved in all of the mentioned activities except conduction of food. Parenchyma cells are responsible for photosynthesis, as they contain chloroplasts and can produce food through the process of photosynthesis. They also play a role in the structure of fruits, as they can provide support and contribute to the overall texture of the fruit. Additionally, parenchyma cells can store food, as they have large vacuoles that can store nutrients. However, they are not involved in the conduction of food, as this function is typically carried out by other types of cells, such as sieve tube elements in phloem tissue.
3.
The substance that strengthens and waterproofs cell walls is
Correct Answer
B. Lignin.
Explanation
Lignin is a substance that strengthens and waterproofs cell walls. It is a complex polymer found in the cell walls of many plants, providing rigidity and support. Lignin also helps plants resist microbial attack and prevents water loss. It is a key component in the structural integrity of plant tissues and is particularly abundant in woody plants. Unlike cutin, pectin, suberin, and chitin, which also have roles in cell wall structure or protection, lignin is specifically known for its strength and waterproofing properties.
4.
Cells that are the main water-conducting cells of a plant are
Correct Answer
B. Xylem tubes.
Explanation
The xylem tubes are the main water-conducting cells of a plant. Xylem tissue is responsible for transporting water and minerals from the roots to the rest of the plant. These tubes are composed of specialized cells called tracheids and vessel elements that are arranged end to end, forming a continuous pathway for water movement. Unlike sclereids, which are involved in support and protection, and sieve tubes and parenchyma, which have different functions in the plant, xylem tubes specifically serve the purpose of water transportation. Therefore, the correct answer is xylem tubes.
5.
Gaseous exchange occurs in plants through these structures in the epidermis.
Correct Answer
C. Stomata
Explanation
Stomata are the correct answer because they are small openings found on the surface of leaves and stems that allow for the exchange of gases, such as oxygen and carbon dioxide, with the surrounding environment. These structures are responsible for the intake of carbon dioxide needed for photosynthesis and the release of oxygen as a byproduct. Stomata also play a role in regulating water loss through transpiration.
6.
A cotyledon is which of the following?
Correct Answer
D. Seed leaf
Explanation
A cotyledon is a seed leaf. It is part of the embryo of a seed and serves as a food source for the developing plant. Cotyledons are usually the first leaves to emerge from the seed when it germinates. They provide the necessary nutrients for the young plant until it is able to produce its own food through photosynthesis.
7.
Deciduous plants
Correct Answer
E. May shed their leaves as winter approaches or retain the dead brown leaves until new leaves emerge in the spring.
Explanation
Deciduous plants have the ability to shed their leaves as winter approaches or retain the dead brown leaves until new leaves emerge in the spring. This characteristic allows them to adapt to changing environmental conditions and conserve energy during the winter months. By shedding their leaves, deciduous plants reduce water loss and protect themselves from freezing temperatures. Alternatively, by retaining the dead brown leaves, they provide some protection for new leaf buds and can continue photosynthesis during milder winter periods. This flexibility in leaf retention strategies is a key characteristic of deciduous plants.
8.
Photosynthesis takes place in the
Correct Answer
E. MesopHyll tissue.
Explanation
Photosynthesis is the process by which plants convert sunlight into energy. It occurs in the mesophyll tissue, which is found in the middle layer of the leaf. This tissue contains chloroplasts, which are responsible for capturing sunlight and carrying out the photosynthetic reactions. The other options, such as stomata, cuticle, vascular bundles, and lower and upper epidermis, are not directly involved in the photosynthesis process. The stomata are responsible for gas exchange, the cuticle is the waxy layer that protects the leaf, the vascular bundles transport water and nutrients, and the epidermis provides a protective covering for the leaf.
9.
Mitosis takes place in which region of the root?
Correct Answer
D. Apical meristem region
Explanation
Mitosis takes place in the apical meristem region of the root. The apical meristem is a region of actively dividing cells located at the tip of the root. This region is responsible for the growth and development of the root. Mitosis is the process of cell division that occurs in this region, allowing for the production of new cells that contribute to root elongation and differentiation. Therefore, the apical meristem region is the correct answer.
10.
Which provides horizontal transport of material in stems and roots?
Correct Answer
A. Ray cells
Explanation
Ray cells are responsible for the horizontal transport of materials in stems and roots. These cells are found in the vascular cambium, which is a layer of meristematic tissue that produces secondary xylem and phloem. Ray cells are oriented radially and extend horizontally across the stem or root. They transport water, nutrients, and other substances laterally between the xylem and phloem, allowing for efficient distribution throughout the plant.