1.
Which of the following would likely not contribute to the surface area available for water absorption...
Correct Answer
B. Endodermis
Explanation
The endodermis is a layer of cells in the root that acts as a barrier to control the movement of water and nutrients. It is responsible for selective absorption and prevents the free flow of water into the root. Unlike root hairs and fungi associated with the roots, the endodermis does not contribute to the surface area available for water absorption. Therefore, it is the likely answer that would not contribute to the surface area available for water absorption.
2.
What is the main cause of guttation in plants?
Correct Answer
A. Root pressure
Explanation
Root pressure is the main cause of guttation in plants. Guttation occurs when excess water is forced out of the plant through specialized structures called hydathodes. This happens when root pressure, generated by active transport of ions into the root cells, increases the water pressure in the xylem. As a result, water is pushed up into the leaves and forced out through the hydathodes. Transpiration, the loss of water vapor through the stomata, is not the main cause of guttation. Plant injury is also not a cause of guttation.
3.
Most of the water with xylem vessles moves toward the top of a tree
Correct Answer
B. Evaporation of water through stomata
Explanation
The correct answer is "Evaporation of water through stomata." This is because water is lost through the stomata, which are small openings on the surface of leaves. This process is called transpiration. As water evaporates from the leaves, it creates a negative pressure, or tension, in the xylem vessels, pulling water up from the roots to replace the lost water. This is known as the transpiration pull, and it is the main mechanism responsible for the movement of water and nutrients up the tree.
4.
Water potential is generally most negative in which of the following parts of a plant?
Correct Answer
B. MesopHyll cells of the leaf
Explanation
Water potential is generally most negative in the mesophyll cells of the leaf. This is because mesophyll cells are responsible for photosynthesis, which requires a constant supply of water. The negative water potential in the mesophyll cells helps to create a gradient that allows water to move from the roots, through the xylem vessels, and into the leaf cells. This negative pressure also helps to pull water up the plant against gravity. Therefore, the mesophyll cells have the most negative water potential to ensure a continuous supply of water for photosynthesis and plant growth.
5.
The following are generally observed among animals except
Correct Answer
C. AutotropHic nutrition
Explanation
Autotrophic nutrition refers to the ability of organisms to produce their own food through photosynthesis or chemosynthesis. This process is commonly observed in plants and some bacteria, but not in animals. Animals rely on heterotrophic nutrition, where they obtain nutrients by consuming other organisms. Therefore, autotrophic nutrition is the correct answer as it is not generally observed among animals.
6.
Assuming that all of the following events occur, what is the correct sequence in which the following processes: gastrulation,metamorphosis
Correct Answer
C. 3,4,1,2
Explanation
The correct sequence of events is 3, 4, 1, 2. This means that the process of gastrulation occurs first, followed by metamorphosis, then process 1, and finally process 2.
7.
What should animals as diverse as corals
Correct Answer
A. Presence of Hox genes
Explanation
The presence of Hox genes is a determining factor for animals as diverse as corals. Hox genes play a crucial role in the development of body plans and the arrangement of body parts during embryonic development. These genes control the expression of other genes, influencing the formation of different body structures and organs. The presence of Hox genes allows for the development of complex body plans and the differentiation of specialized tissues in animals. Therefore, the presence of Hox genes is a key characteristic that contributes to the diversity of animal species, including corals.
8.
If a multicellular animal lacks true tissues
Correct Answer
C. Parazoa
Explanation
Parazoa is the correct answer because it refers to multicellular animals that lack true tissues. True tissues are specialized groups of cells that work together to perform specific functions. In parazoans, such as sponges, the cells are loosely organized and do not form distinct tissues. Instead, they have different types of cells that can perform various functions, but they do not work together in a coordinated manner like in eumetazoans (animals with true tissues). Metazoa is a broader term that refers to all multicellular animals, including both eumetazoans and parazoans.
9.
The major banches of eumetazoa are the radiata and bilateria
Correct Answer
A. Body symmetry
Explanation
The major branches of Eumetazoa, which are the Radiata and Bilateria, are distinguished based on their body symmetry. Radiata have radial symmetry, meaning their body parts are arranged around a central axis, like spokes on a wheel. Bilateria, on the other hand, have bilateral symmetry, meaning their body is divided into two mirrored halves. This distinction in body symmetry is a key characteristic used to classify and differentiate these two major branches of Eumetazoa.
10.
Cephalization is generally associated
Correct Answer
A. A sessile existence
Explanation
Cephalization is generally associated with a sessile existence. This means that organisms that are fixed or immobile, such as plants or some types of marine animals, tend to have a more concentrated development of sensory and neural structures in their heads or anterior regions. This allows them to efficiently process and respond to stimuli in their environment, despite their inability to move. Having a brain is not necessarily associated with cephalization, as there are organisms with distributed nervous systems that do not have a centralized brain.