Cell Transport and Division

Cell transport mechanisms are crucial for maintaining cellular function. The three main types are:

1. Diffusion: The movement of particles from an area of high concentration to an area of low concentration, requiring no energy.
2. Osmosis: The diffusion of water molecules across a semi-permeable membrane.
3. Active transport: The movement of molecules against the concentration gradient, requiring energy.

Example: Oxygen and glucose enter cells through diffusion, while carbon dioxide exits cells through the same process.

Factors affecting the rate of diffusion include concentration gradient, temperature, and surface area.

Mitosis is the process of cell division for growth and repair, creating two genetically identical daughter cells from one parent cell. The cell cycle encompasses the life of a cell, including its growth, function, and DNA replication in preparation for mitosis.

Definition: Chromosomes are structures in the nucleus made up of DNA, typically found in pairs.

Genes are small sections of DNA within chromosomes that code for protein production. Ribosomes use this genetic information to synthesize proteins by joining amino acids together.

Active Transport and Surface Area to Volume Ratio

Active transport is crucial for moving molecules against the concentration gradient, requiring energy in the form of ATP. This process is essential in both plant and animal cells for various functions.

Example: In plants, active transport allows mineral ions to be absorbed into root hair cells for healthy growth. In animals, it enables glucose absorption into the bloodstream when diffusion is insufficient.

The surface area to volume ratio is a critical factor in cellular efficiency. A larger surface area compared to volume allows for faster rates of diffusion and more efficient exchange of materials.

Highlight: Efficient exchange surfaces in organisms include the small intestine and lungs in mammals, gills in fish, and roots and leaves in plants.

Osmosis, a specific type of diffusion, involves the movement of water molecules from a dilute solution to a more concentrated solution across a semi-permeable membrane. This process is vital for maintaining water balance in cells.

Vocabulary: The concentration gradient refers to the difference in concentration of a substance between two areas, driving the direction of diffusion.

Understanding these cellular processes and structures is fundamental to comprehending the complex world of plant cell structure and function in biology, as well as the broader field of cell biology.