Plants/Animal Diversity AP Bio

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.