Cell Biology Quiz

Prokaryotic and Eukaryotic Cells

• Prokaryotes lack membrane-bound organelles.

• Eukaryotes possess membrane-bound organelles.

• Both prokaryotic and eukaryotic cells share a cell membrane, genetic material, ribosomes, and cytoplasm.

Cell Theory

• All organisms are made of cells.
• Cells come from pre-existing cells.
• Cells are the structural and functional units of life.

Cell Cycle

• Interphase: Cell growth, DNA replication, and preparation for division.
  • G1 Phase: Cell growth and preparation for DNA replication.
  • S Phase: DNA replicates; two copies of chromosomes are formed.
  • G2 Phase: Further cell growth, checks for readiness for division.
• Mitosis: Cell division resulting in two identical daughter cells.
  • Prophase: Breakdown of nuclear envelope, spindle fiber formation, DNA condenses into chromosomes, and sister chromatids join at the centromere.
  • Metaphase: Chromosomes align at the metaphase plate.
  • Anaphase: Sister chromatids separate and move to opposite poles.
  • Telophase: Nuclear envelope reforms, chromosomes decondense, and cleavage furrow forms.
• Cytokinesis: Cytoplasm and plasma membrane divide, forming two daughter cells.

Cell Structures

• Chromosome: Thread-like DNA structure carrying genetic information.
• Chromatin: DNA and protein complex for packaging and gene regulation.
• Sister Chromatids: Two identical copies of a replicated chromosome, joined at the centromere.
• Centromere: Region where sister chromatids are joined and spindle fibers attach.
• Organelles: Sub-cellular structures with specific functions.
  • Nucleus: Controls cell activities.
  • Mitochondria: Powerhouses of the cell, generate energy.
  • Ribosomes: Assemble proteins.
  • Endoplasmic Reticulum: Synthesizes and transports proteins and lipids.
  • Vesicles: Transport materials within the cell.
  • Golgi Body: Packages and exports proteins.
  • Vacuoles: Storage structures.
  • Cytoskeleton: Maintains cell shape and organelle position.
  • Cell Wall: Provides strength and protection (plant cells).
  • Chloroplasts: Conduct photosynthesis (plant cells).
  • Cell Membrane: Barrier for cell (enters and exits).
  • Cytoplasm: Substance that fills the cell, and keeps organelles in place.
  • Lysosomes: Digestive sacs of the cell.
  • Centrioles: Involved in cell division.

Cancer

• Cancer is caused by uncontrolled cell growth.
• Benign tumor: Non-cancerous; does not spread.
• Malignant tumor: Cancerous; invades surrounding tissues and spreads (metastasis.)
• Metastasis: Cancer cells detach from primary tumor, travel in the bloodstream or lymphatic system, and form secondary tumors elsewhere.
• Carcinogen: Cancer-causing substance. Examples: alcohol, arsenic, UV rays, diesel exhaust, tobacco.

Specialized Cells

• Specialized cells have unique structures and functions.
  • Sperm: Fertilization.
  • Red Blood Cells: Oxygen transport.
  • Egg Cells: Development.
  • Villi: Nutrient absorption.

Tissues, Organs, and Organ Systems

• Tissue: Group of similar cells performing a specific function.
• Organ: Group of tissues working together for a common function.
• Organ System: Multiple organs functioning together for a complex function.
• Levels of Organization (smallest to largest): Organelles, cells, tissues, organs, organ systems, organism

Digestive System

• Mechanical digestion: Physical breakdown of food.
• Chemical digestion: Enzyme breakdown of food.
• Accessory organs: Liver, gallbladder, pancreas.

Respiratory System

• Gas exchange: Oxygen and carbon dioxide exchange between alveoli and capillaries.
• Factors for efficient gas exchange include a large surface area for exchange and a thin diffusion distance.

Circulatory System

• Components: Heart, blood, blood vessels.
• Heart Chambers (blood flow order): Right atrium, right ventricle, left atrium, left ventricle.
• Arteries: Carry blood away from the heart.
• Veins: Carry blood to the heart.
• Blood Components: Red blood cells (oxygen transport), white blood cells (immune function), platelets (blood clotting), plasma (liquid component).

Musculoskeletal System

• Muscles: Move the body.
• Bones: Support and protect the body.

Nervous System

• Central nervous system (CNS): Brain and spinal cord.
• Peripheral nervous system (PNS): Nerves connecting CNS to body parts.
• Neuron: Nerve cell.

Interactions Between Organ Systems

• Digestive and circulatory: Breakdown of food fuels travel in circulation.
• Circulatory and respiratory: Oxygenated blood flows to tissues from lungs; return with carbon dioxide.
• Respiratory and musculoskeletal: Muscles (diaphragm) facilitate breathing.
• Musculoskeletal and nervous: Muscles are controlled by nerves.