Mass/weight, density, Newton’s laws, friction, moments, circular motion, momentum, and pressure.

Measurement tools, scalars/vectors, resultant vectors, and motion kinematics (graphs, acceleration, free fall).

Covers biological coordination systems, contrasting quick electric signals (Nervous System) with sustained chemical messages (Hormones). Emphasis placed on mechanisms like negative feedback (glucose homeostasis) and comparison of coordination methods across animals and plants.

Uses of Energy Released by Respiration Cells use the energy released during respiration for various essential life processes: Energy Use Description Muscle contraction Energy for movement and physical activity Protein synthesis Building proteins from amino acids for growth and repair Cell division Energy required for mitosis and reproduction Active transport Moving substances against concentration gradients Growth Building new cells and tissues Nerve impulses Electrical signals for communication Body temperature Maintaining metabolic heat Aerobic Respiration Definition Aerobic respiration is using oxygen to break down nutrients for energy. ...

Introduction Gas exchange in humans is the process by which oxygen enters the body and carbon dioxide is removed. This occurs primarily in the lungs through a system of specialized structures optimized for efficient gas transfer. Features of Gas Exchange Surfaces Four Essential Features For effective gas exchange, the surface must have four key characteristics: Feature Purpose How it Works Large surface area More area for gas exchange Many alveoli create large total area (~70 m² in adult lungs) Thin surface Short diffusion distance Alveoli and capillary walls are one cell thick (~0.5 μm) Good blood supply Maintain concentration gradient Capillaries carry away O₂, bring CO₂ Good ventilation Maintain concentration gradient Breathing brings in O₂, removes CO₂ How These Features Work Together Large surface area = more sites for O₂ and CO₂ to cross Thin surface = faster diffusion (shorter distance) Good blood supply = blood constantly removes O₂, loads with CO₂ Good ventilation = fresh air constantly replaces stale air ...