science exam end of term

Formula for magnification

$$\text{Magnification} = \frac{\text{Image size}}{\text{Actual size}}$$

Three structures found in plant cells but absent in animal cells

Cell wall, vacuole, and chloroplasts

Function of ribosomes

To make proteins for the cell

Structural adaptations of a red blood cell

A biconcave shape to give a large surface area for absorbing oxygen, and no nucleus to carry more oxygen

Diffusion

The spreading out of particles from an area of higher concentration to an area of lower concentration

Euglena

A single-celled organism that has a flagellum to swim, an eyespot to detect light, and chloroplasts to make food from sunlight

Arrangement and movement of particles in a liquid

Arranged close together in a random pattern, moving and sliding past each other in all directions

Formula for calculating density

$$\text{Density} = \frac{\text{Mass}}{\text{Volume}}$$

Difference between boiling and evaporation

Boiling occurs throughout the liquid at a specific boiling point, whereas evaporation occurs only at the surface and can take place at any temperature below the boiling point

Sublimation

When a solid changes directly into a gas without melting into a liquid first

Standard international unit of force

Newton ($N$)

Hooke's Law

The extension of a spring or elastic object is directly proportional to the force applied to it

Drag force

A type of friction that slows down objects moving through air or water

Three examples of non-contact forces

Gravitational force, electrostatic force, and magnetic force

Resultant force on an object travelling at a constant velocity

$0\,N$, because the forward and resistive forces are balanced