Biology Unit 1 & 2: Organ Systems and Plants

Study Notes

Diffusion: Movement of particles from high concentration to low concentration. Occurs in gases, liquids, and solutions. Example: Oxygen diffuses from alveoli to blood, and carbon dioxide diffuses out.
Respiratory System: Involves nose, trachea, bronchi, lungs, and alveoli. Primary function is gas exchange (oxygen in, carbon dioxide out). Mechanism: Air enters lungs, reaches alveoli, and oxygen diffuses into the blood.
Blood Components: Red blood cells carry oxygen using hemoglobin. White blood cells fight infection. Platelets help with clotting. Plasma (liquid portion) transports nutrients, hormones, and waste; regulates temperature.
Renal System: Includes kidneys, ureters, bladder, and urethra. Function: Filters blood to remove waste (urea, excess salts), and maintains water and electrolyte balance. Urine formation: filtration, reabsorption, and secretion.

Mineral Deficiency in Plants: Nitrogen: needed for protein synthesis (yellowing leaves if deficient). Phosphorus: for energy transfer (ATP) (poor root growth if deficient). Potassium: aids enzyme activation (weak stems if deficient).
Photosynthesis: Equation: 6CO2 + 6H2O → C6H12O6 + 6O2. Occurs in chloroplasts using chlorophyll. Light-dependent reactions convert light to chemical energy. Calvin cycle synthesizes glucose.
Water and Mineral Transport in Plants: Water absorbed by roots via osmosis. Travels through xylem to leaves. Minerals absorbed actively; essential for plant metabolism.
Carbon Cycle: Movement of carbon through atmosphere, organisms, and Earth. Includes photosynthesis, respiration, decomposition, and fossil fuel combustion.

Calculating Speed: Formula: speed = distance / time. Units: m/s, km/h.
Interpreting Distance/Time Graphs: Slope of graph indicates speed. Flat line = stationary object. Steeper slope = higher speed.
Effects of Forces on Motion: Force is a push or pull. Effects: start/stop motion, change direction, or shape. Balanced forces: No motion change. Unbalanced forces: Cause acceleration. Calculating moments: Moment = force * distance from pivot. Units: Nm (Newton-meters). Examples: levers, seesaws.

Atoms: Smallest unit of matter; consists of protons, neutrons, and electrons. Atomic number: Number of protons; mass number = Protons + Neutrons.
Electrostatics: Study of stationary electric charges. Like charges repel; opposite charges attract. Examples: static electricity, lightning.
Reactions of Metals: Reactivity series determines how metals react with water, acids, etc. Example: Sodium reacts violently with water, gold does not.
Using Word Equations: Examples: Magnesium + Oxygen -> Magnesium oxide. Represents reactants and products in chemical reactions.
Sorting Substances by Reactivity: Metals are ordered by their ability to displace others in compounds. Example: Zinc displaces copper from copper sulfate.

Water Pressure: Increases with depth. Examples: deep-sea diving, dams.
Pure Substances & Mixtures: Pure substances: Single type of particle (e.g., distilled water); mixtures: Combination of two or more substances (e.g., salt water).
Solubility & Chromatography: Solubility: Maximum amount of solute dissolved in a solvent. Chromatography: Technique to separate mixtures based on solubility and adsorption.