Y7 Biology Quiz On Unit 3

This statement is false. While all body cells share some similarities in structure and function, they are not exactly the same. Different types of cells have specific structures and functions that are necessary for their specialized roles in the body. For example, nerve cells have long extensions called axons that allow them to transmit electrical signals, while muscle cells have unique proteins that enable them to contract and generate force. Therefore, the structure and function of cells vary depending on their type and purpose in the body.

The cell membrane controls what enters and exits a cell, acting as a selective barrier. It is found in both animal and plant cells, making it the correct answer. The cell vacuole is responsible for storing water and other substances, the cell wall provides structural support in plant cells, and cell thickness is not a specific component found in cells.

The statement is false because the nucleus is found in both animal and plant cells. The nucleus is a membrane-bound organelle that contains the cell's genetic material, including DNA. It is responsible for controlling the cell's activities and is present in the cells of both animals and plants.

Plant cells carry out photosynthesis because they contain chloroplasts. Chloroplasts are specialized organelles found in plant cells that contain chlorophyll, a pigment responsible for capturing light energy. During photosynthesis, chloroplasts use this light energy to convert carbon dioxide and water into glucose and oxygen. This process is vital for plants as it enables them to produce their own food and release oxygen as a byproduct. Therefore, the presence of chloroplasts allows plant cells to carry out photosynthesis efficiently.

Red blood cells, also known as erythrocytes, are the correct answer. Red blood cells are responsible for carrying oxygen throughout the body. Their biconcave shape allows for a larger surface area, which facilitates the exchange of oxygen and carbon dioxide. This shape also enables them to be flexible and squeeze through narrow capillaries.

The cell membrane is a structure found in both plant and animal cells. It acts as a barrier, controlling the movement of substances in and out of the cell. The nucleus is also found in both plant and animal cells and is the control center of the cell, containing the genetic material. The cytoplasm is a gel-like substance that fills the cell and contains various organelles. Therefore, both the nucleus and cytoplasm are found in both plant and animal cells.

The extension of the root hair cell increases the surface area for absorption of water from the soil. This is because the root hair cells are long and slender, which allows them to penetrate between soil particles. The increased surface area provided by the extensions of the root hair cell allows for more contact with the soil particles, increasing the absorption of water and nutrients. This adaptation is crucial for the plant to efficiently uptake water and nutrients from the soil for its growth and survival.

Yeast is used to help make bread because it is a type of fungus that ferments the dough, causing it to rise and giving the bread its fluffy texture. On the other hand, bacteria are used to change milk into yogurt through the process of fermentation. The bacteria consume the lactose in the milk and produce lactic acid, which thickens the milk and gives yogurt its tangy flavor and creamy consistency.

Root hair cells are specialized cells found in the roots of plants. Their main function is to absorb water and minerals from the soil. These cells have long, thin projections called root hairs that increase the surface area of the root, allowing for more efficient absorption of water and minerals. This helps the plant to obtain the necessary nutrients for growth and development.