Cell Structure and Function Quiz

Cell Structure and Function

• Cells are the fundamental units of life, exhibiting a complex organization of structures and functions.
• Prokaryotic cells lack a nucleus and membrane-bound organelles.
• Eukaryotic cells, present in plants and animals, possess a nucleus and membrane-bound organelles.
• Key organelles include mitochondria (energy production), ribosomes (protein synthesis), endoplasmic reticulum (protein and lipid synthesis), Golgi apparatus (protein modification and sorting), and lysosomes (waste breakdown).
• Plant cells feature chloroplasts (photosynthesis) and a cell wall (structural support).
• The cell membrane regulates substance passage into and out of the cell.

Cell Metabolism

• Metabolism encompasses all chemical reactions within a cell.
• Catabolism breaks down complex molecules into simpler ones, releasing energy.
• Anabolism builds complex molecules from simpler ones, requiring energy.
• Cellular respiration, a crucial catabolic process, generates ATP, the cell's energy currency.
• Photosynthesis, unique to plants, converts light energy into chemical energy (glucose).
• Enzymes accelerate metabolic reactions without being consumed.

Cell Communication

• Cells communicate via various mechanisms, essential for multicellular organism functions.
• Cell signaling involves a cascade of events triggered by external stimuli, leading to specific responses.
• Hormones, neurotransmitters, and other signaling molecules mediate cell communication.
• Various signaling pathways exist, each with unique components and functions.
• Receptor proteins on the cell surface or within the cell receive and transmit signals.

Cell Growth and Division

• Cells grow and divide to maintain tissue and organ integrity.
• The cell cycle encompasses stages from cell division to the next.
• Mitosis is nuclear division, ensuring identical genetic material in daughter cells.
• Meiosis produces haploid gametes, vital for sexual reproduction.
• Growth factors and regulatory proteins control cell cycle progression, preventing uncontrolled growth (cancer).

Genetics and Heredity

• The genetic material is DNA, organized into chromosomes.
• DNA holds the instructions for cell building and operation.
• Genes are DNA segments coding for proteins.
• Gene expression involves DNA transcription into RNA and RNA translation into proteins.
• Inheritance patterns follow predictable principles, including Mendelian genetics.
• DNA mutations cause variations and can lead to traits and diseases.