Biology: Cell Transport and Photosynthesis

Cell Transport

• Simple diffusion: Movement of molecules from high to low concentration, no energy required. Examples include oxygen and carbon dioxide across cell membranes.
• Facilitated diffusion: Movement of molecules from high to low concentration, assisted by transport proteins; still no energy required. Examples include glucose transport.

Photosynthesis

• Process: Plants use light energy to convert carbon dioxide and water into glucose (sugar) and oxygen.
• Equation: 6CO₂ + 6H₂O + Light Energy → C₆H₁₂O₆ + 6O₂
• Location: Chloroplasts (specifically, chlorophyll) in plant cells.
• Importance: Produces food for the plant and oxygen for the atmosphere.

Cellular Respiration

• Process: Breakdown of glucose to release energy in the form of ATP (adenosine triphosphate). A crucial energy-production process for all living cells.
• Equation: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + Energy (ATP)
• Types: Aerobic (requires oxygen) and anaerobic (without oxygen).

Animal vs. Plant Cells

• Animal Cells: Typically lack cell walls, chloroplasts, and large central vacuoles.
• Plant Cells: Possess cell walls, chloroplasts, and a large central vacuole for storage and support.

Tonicity (Hypertonic, Hypotonic, Isotonic)

• Hypertonic: Solution with higher solute concentration compared to the cell. Water moves out of the cell, potentially causing it to shrink.
• Hypotonic: Solution with lower solute concentration compared to the cell. Water moves into the cell, potentially causing it to swell or burst.
• Isotonic: Solution with equal solute concentration to the cell. Water movement is balanced in both directions, maintaining cell shape.

Enzymes

• Biological catalysts: Speed up chemical reactions in living organisms.
• Specificity: Each enzyme catalyzes a specific reaction.
• Active site: Region of the enzyme where the substrate binds.
• Factors affecting enzyme activity: Temperature, pH, and substrate concentration.

Biomolecules

• Carbohydrates: Provide energy; composed of carbon, hydrogen, and oxygen.
• Lipids: Store energy, insulation; composed of carbon, hydrogen, and oxygen.
• Proteins: Build cells, control reactions; composed of amino acids.
• Nucleic acids: Store genetic information; composed of nucleotides.

Independent and Dependent Variables

• Independent variable: The factor the researcher manipulates.
• Dependent variable: The factor the researcher measures.

Control vs. Experimental Groups

• Control group: Used for comparison; receives no treatment or a standard treatment.
• Experimental group: Receives the treatment being tested.

Explore the fundamental processes of cell transport, photosynthesis, and cellular respiration. This quiz covers simple and facilitated diffusion, the photosynthesis equation, and the importance of cellular respiration for energy production. Test your knowledge of these essential biological concepts.