PRAXIS II: Biology Content Knowledge Exam

Explanation
Homeostasis refers to the maintenance of a stable and vital internal environment in living organisms. It involves various physiological processes that help regulate and balance the body's temperature, pH levels, blood sugar levels, and other factors necessary for proper functioning. Tropism refers to the growth or movement of a plant in response to external stimuli, while flaccidity and turgidity refer to the state of plant cells in terms of their firmness. Therefore, the correct answer is homeostasis.

Explanation
Charles Darwin is the correct answer because he is known for his contributions to the theory of evolution through natural selection, not specifically for his work in cell biology. Mathias Schleiden, Theodor Schwann, and Robert Hooke, on the other hand, are all known for their significant contributions to the field of cell biology.

Explanation
The basic unit of life is the cell. Cells are the smallest structural and functional units of living organisms. They are responsible for carrying out all the necessary processes of life, such as metabolism, growth, and reproduction. Tissues, organs, and systems are made up of cells, but they are not the fundamental unit of life.

Explanation
The question is asking for something that is not a level of organization. The options given are "Skeleton," "Organ," "System," and "Tissue." Out of these options, "Skeleton" is not a level of organization. The levels of organization in the human body are organized from smallest to largest, starting with cells, then tissues, organs, and finally systems. The skeleton is a part of the body, but it is not a level of organization itself.

Explanation
The concept of evolution was introduced by Jean Lamarck in 1809. This was the year when Lamarck published his book "Philosophie Zoologique" which outlined his theory of evolution. In this book, Lamarck proposed that species change over time through the inheritance of acquired characteristics. This idea was a significant departure from the prevailing belief in fixity of species and laid the foundation for the later development of Charles Darwin's theory of natural selection.

Explanation
Prokaryotes have no true nucleus. Unlike eukaryotes, which have a well-defined nucleus containing their genetic material, prokaryotes lack a membrane-bound nucleus. Instead, their genetic material is dispersed in the cytoplasm. Bacteria and archaea are examples of prokaryotes. Viruses, on the other hand, are not considered living organisms and do not have cells or a nucleus.

Explanation
Mitochondria is the correct answer because it is the part of the cell that contains genetic material. Mitochondria have their own DNA, known as mitochondrial DNA, which carries genetic information and is involved in the production of proteins essential for the cell's function. The genetic material in mitochondria is separate from the DNA found in the cell's nucleus, which is responsible for the majority of genetic information.

Explanation
Mitochondria is known as the powerhouse of the cell because it is responsible for producing the majority of the cell's energy in the form of ATP (adenosine triphosphate) through cellular respiration. It contains its own DNA and is capable of self-replication. The Golgi apparatus is involved in processing and packaging proteins, the nucleus contains the cell's genetic material, and ribosomes are responsible for protein synthesis. Therefore, the correct answer is mitochondria.

Explanation
Autotrophs are organisms that are able to synthesize their own food through processes such as photosynthesis or chemosynthesis. They are capable of converting inorganic substances into organic compounds, which can be used as a source of energy. Unlike heterotrophs, which rely on consuming other organisms for their energy needs, autotrophs are self-sufficient in their food production. Therefore, autotrophs are the correct answer to the question.

Explanation
Ecology is the branch of biology that studies the relationship between organisms and their environment. It focuses on understanding how organisms interact with each other and with their physical surroundings. This includes studying topics such as population dynamics, community structure, and the flow of energy and nutrients through ecosystems. By studying ecology, scientists can gain insights into how organisms are adapted to their environment and how they respond to changes in their surroundings.