Give 3 characteristics of cells that are different comparing plant and animal cells found in the unit.
1. Cell wall: Plant cells have a rigid cell wall composed of cellulose, which provides structural support and protection for the cell. Animal cells lack a cell wall and instead have a flexible cell membrane.
2. Chloroplasts: Plant cells contain chloroplasts, specialized organelles responsible for photosynthesis. Chloroplasts contain chlorophyll, the pigment that captures sunlight and converts it into chemical energy. Animal cells lack chloroplasts as they are unable to carry out photosynthesis.
3. Vacuoles: Plant cells typically have large central vacuoles that occupy a significant portion of the cell's volume. These vacuoles play a role in maintaining turgor pressure, storing water and nutrients, and storing waste products. Animal cells may have smaller vacuoles or none at all, serving different functions such as storing water or maintaining osmotic balance.
Give the functions of a cell membrane and mitochondria.
Function of the cell membrane:
1. Physical barrier: The cell membrane acts as a selective barrier, separating the internal environment of the cell from the external environment. It regulates the movement of substances in and out of the cell, allowing certain molecules to enter or exit while preventing the passage of others.
2. Protection and support: The cell membrane provides protection to the cell by preventing the entry of harmful substances and pathogens. It also provides support to the cell, maintaining its shape and structure.
3. Cell communication: The cell membrane plays a crucial role in cellular communication. It contains receptors that can detect and bind to specific molecules, transmitting signals from the external environment to the cell's interior and vice versa. These signals are essential for various cellular processes, including growth, development, and response to stimuli.
Function of mitochondria:
1. Energy production: Mitochondria are often referred to as the "powerhouses" of the cell because they are responsible for producing energy in the form of adenosine triphosphate (ATP) through a process called cellular respiration. Mitochondria convert the chemical energy stored in nutrients into ATP, which is used as a source of energy for cellular activities.
2. Metabolism regulation: Mitochondria play a role in regulating cellular metabolism. They are involved in processes such as the breakdown of fatty acids, amino acids, and carbohydrates, which provide substrates for energy production. Mitochondria also participate in various metabolic pathways, including the citric acid cycle and fatty acid synthesis.
3. Calcium regulation: Mitochondria are involved in the regulation of calcium levels within the cell. They help maintain the appropriate concentration of calcium ions, which is crucial for various cellular processes such as muscle contraction, cell signaling, and enzymatic reactions. Mitochondria can also store and release calcium ions in response to specific cellular signals.
Give the one function of a cell membrane and mitochondria.
One function of the cell membrane is to regulate the movement of substances in and out of the cell, controlling which molecules can enter or exit.
The one function of mitochondria is to produce energy in the form of ATP through cellular respiration.