Grade 9 Biology Quiz Questions And Answers

Explanation
In photosynthesis, the term "photo" is derived from the Greek word for light. Photosynthesis is a complex process carried out by plants, algae, and certain bacteria, where light energy is captured and utilized to convert carbon dioxide and water into glucose and oxygen. Light plays a central role in the initial phase, where pigments such as chlorophyll absorb light energy during the photochemical reactions, initiating the conversion of light energy into chemical energy stored in glucose molecules. The prefix "photo-" in photosynthesis emphasizes the essential role of light in driving this vital biological process.

Explanation
Root hair cells are specialized cells found in the root system of plants. Their main function is to absorb water and minerals/nutrients from the soil. These cells have long, thin projections called root hairs that increase the surface area for absorption. They have a large number of transport proteins in their cell membranes that facilitate the uptake of water and nutrients. Therefore, the correct answer is "To absorb water and minerals/nutrients."

Explanation
The total magnification of a microscope is calculated by multiplying the magnification of the ocular lens (eyepiece) by the magnification of the objective lens. In this case, if the ocular lens has a magnification of 10 times and the objective lens has a magnification of 20 times:

Total Magnification = Ocular Lens Magnification × Objective Lens Magnification
                  = 10 × 20
                  = 200

So, the total magnification of the microscope would be 200 times.

Explanation
DNA stands for Deoxyribonucleic acid. It is a molecule that carries the genetic instructions for the growth, development, functioning, and reproduction of all known organisms. It is composed of two long chains of nucleotides that are twisted into a double helix structure. The nucleotides in DNA contain a sugar called deoxyribose, hence the name Deoxyribonucleic acid. This molecule is essential for the storage and transmission of genetic information from one generation to the next.

Explanation
Plants contain vascular bundles, which are similar to human veins and arteries. These vascular bundles contain two things: one is responsible for carrying water, and the other is responsible for carrying a glucose solution. The two things referred to in the question are phloem and xylem. Phloem is the tissue responsible for transporting the glucose solution, while xylem is responsible for transporting water.

Explanation
The four bases that make up the code for DNA are T, A, G, and C. These bases are the building blocks of DNA and are responsible for carrying the genetic information. T (thymine) pairs with A (adenine), and G (guanine) pairs with C (cytosine) to form the double helix structure of DNA. These base pairs determine the genetic code and are essential for DNA replication and protein synthesis.

Explanation
Photosynthesis is the process by which plants convert sunlight into energy. It occurs in the chloroplasts, which contain chlorophyll, the pigment responsible for capturing sunlight. The chloroplasts are found in the cells of the plant's leaves, where they absorb light energy and use it to convert carbon dioxide and water into glucose and oxygen. The nucleus is responsible for controlling the cell's activities, the vacuole stores water and other substances, and the mitochondria produce energy through cellular respiration. Therefore, the correct answer is chloroplasts/chlorophyll.

Explanation
The DNA code contains instructions that guide the cell in making proteins. Proteins are essential molecules that perform various functions in the body, such as building and repairing tissues, regulating chemical reactions, and supporting the immune system. DNA is transcribed into RNA, which is then translated into proteins through a process called protein synthesis. Therefore, the correct answer is protein.

Explanation
Animal cells have a nucleus, cytoplasm, and mitochondria. The nucleus is the control center of the cell, containing the genetic material and regulating cell activities. Cytoplasm is a gel-like substance that fills the cell, providing a medium for cellular processes. Mitochondria are the powerhouse of the cell, responsible for generating energy through cellular respiration. Chloroplasts are not present in animal cells, as they are responsible for photosynthesis in plant cells. Cell walls are also absent in animal cells, as they have a cell membrane.

Explanation
The statement is incorrect. Animals without backbones are called invertebrates, not vertebrates. Vertebrates are animals that have a backbone or spinal column.

Explanation
Seeds need water, warmth, and oxygen to germinate. Water is essential for the activation of enzymes that initiate germination. Warmth provides the necessary temperature for the enzymatic reactions to occur. Oxygen is required for respiration, which provides energy for the germination process. Light, although important for the growth of the seedling after germination, is not necessary for the actual germination process itself.

Explanation
Biology is the study of life, encompassing the examination of living organisms, their structure, function, growth, evolution, and distribution. It focuses on understanding the various processes and systems that occur within living organisms, including their interactions with the environment. Therefore, the correct answer is "life" because biology is specifically concerned with the study of living things.