Science Exam Notes PDF

1. Cell Parts and Functions 1. Nucleus: The nucleus controls cell activities and stores the cell’s genetic material (DNA). 2. Cell Membrane: The cell membrane regulates the movement of substances in and out of the cell and protects it from the external environment. 3. Cytoplasm: The cytoplasm hol...

1. Cell Parts and Functions 1. Nucleus: The nucleus controls cell activities and stores the cell’s genetic material (DNA). 2. Cell Membrane: The cell membrane regulates the movement of substances in and out of the cell and protects it from the external environment. 3. Cytoplasm: The cytoplasm holds organelles in place and supports chemical reactions within the cell. *4. Mitochondria: Mitochondria generate energy (ATP) through cellular respiration and regulate metabolism. 5. Endoplasmic Reticulum (ER): The rough ER synthesizes proteins, while the smooth ER synthesizes lipids and detoxifies substances. 6. Ribosomes: Ribosomes are responsible for synthesizing proteins from amino acids. *7. Golgi Apparatus: The Golgi apparatus modifies, packages, and transports proteins and lipids produced by the ER. 8. Lysosomes: Lysosomes contain enzymes that digest waste, old cell parts, and foreign invaders. 9. Vacuole: Vacuoles store nutrients, waste products, and help maintain cell shape (larger in plant cells). 10. Cytoskeleton: The cytoskeleton provides structural support, shape, and helps with cell movement. *11. Centrioles: Centrioles help organize the spindle fibers during cell division in animal cells. 12. Chloroplasts: Chloroplasts (in plant cells) perform photosynthesis, converting light energy into chemical energy. 13. Cell Wall: The cell wall (in plant cells) provides structural support and protection, and helps maintain cell shape. 2. Organ Systems (KNOW DIAGRAMS of Circulatory, Digestive, Respiratory Should be on sidle shows or in binder) Circulatory System: Heart pumps blood, arteries carry oxygenated blood, veins carry deoxygenated blood.  Digestive System: Organs: Mouth, esophagus, stomach, intestines. Functions: Break down food for nutrient absorption. Respiratory System: Organs: Nose, trachea, lungs, alveoli. Gas Exchange: Oxygen enters blood, carbon dioxide exits. 3. Cell Cycle and Mitosis (IPMAT) Phases: 1. Interphase: Cell grows and prepares for division. 2. Mitosis: Prophase: Chromosomes condense. Metaphase: Chromosomes align in the middle. Anaphase: Chromosomes separate. Telophase: Nuclear membranes reform. *3. Cytokinesis: Division of the cytoplasm. 4. Microscope Calculations To put From millimeters to micrometers multiply by 1,000 Field of View (FOV): Low Power: Measure the diameter of FOV. High Power: Use the formula: High Power Fov = Low power fov x low/high Medium FOV: Low power FOV x Low/medium Size of cell = high power fov/ Number of cells 1. Red Blood Cells (RBCs) Function: Transport oxygen to the body and remove carbon dioxide. Contains hemoglobin, a protein that binds oxygen. Lifespan: ~120 days. 2. White Blood Cells (WBCs) Function: Fight infections, bacteria, and viruses. Types: Lymphocytes: Produce antibodies. Neutrophils: Engulf bacteria. 3. Platelets Function: Help in blood clotting to stop bleeding. Lifespan: 7-10 days. DIFFERENCE BETWEEN CANCER AND NORMAL CELLS 1. Normal Cells: Controlled growth and division. Specialize in specific functions (e.g., nerve, muscle cells). Die naturally when damaged or old (apoptosis). 2. Cancer Cells: Uncontrolled growth and rapid division. Fail to specialize; remain immature. Invade surrounding tissues and spread (metastasis). CAUSES AND TREATMENT FOR CANCER Causes: 1. Genetic mutations in DNA. 2. Environmental factors (e.g., UV radiation, smoking). 3. Carcinogens (e.g., asbestos, chemicals). Treatments: 1. Surgery: Removes the tumor. 2. Chemotherapy: Uses drugs to kill cancer cells. 3. Radiation Therapy: Targets and destroys cancer cells with radiation. 4. Immunotherapy: Boosts the immune system to fight cancer. Specialized Cells Perform specific functions. Examples: Nerve Cells (Neurons): Transmit signals. Muscle Cells: Contract for movement. Red Blood Cells: Transport oxygen. Stem Cells Definition: Undifferentiated cells that can divide and become specialized cells. 1. Embryonic Stem Cells: Can become any cell type. 2. Adult (Tissue) Stem Cells: Found in bone marrow; specialize in limited cell types (e.g., blood cells). ORGAN TRANSPLANTATION 1. Definition: Replacing a failing or damaged organ with a donor organ. 2. Organs Donated by Living Donors:  Kidney, part of the liver, lung, or bone marrow. 3. Organs Donated by Deceased Donors: Heart, pancreas, intest