SCIENCE END OF TERM ASSESSMENT PREP

Flashcards with vocabulary terms and definitions.

l

A group of the same organism, living in a particular habitat.

Community

Is made of two or more different populations living in the same area that depends on each other for survival.

Ecosystem- is the interaction of a community of organisms with the non-living parts of their habitat.

Representative sampling

To estimate the total population in an area is an example of random sampling.

Producers

These are organisms that make their own food using sunlight through photosynthesis.They are the foundation of the food chain.

Primary consumers

These are herbivores that eat producers.

Biotic Factors

Living parts of an ecosystem.

Abiotic Factors

Non-living parts of an ecosystem.

Trophic levels

Describe the position an organism occupies in a food chain or food web. Each level represents a step in the flow of energy from one organism to the next.

Secondary consumers

T

Bioaccumulation

Mixture

A combination of two or more substances in any proportions. The substances in a mixture do not combine chemically, so they retain their physical properties.

Compound

A substance made up of two or more different elements that are chemically joined together.

Element

Something that is made up if only one type of atom.

Atom

Like a tiny building block that makes up everything around us

Pure substance

A material that is made up of only one type of particle.

Impure substance

Is made up of two or more different types of particles

Gravity

It is a non contact pull force, which means objects don't need to be touching to exert gravitational force on each other.

Contact Forces

These forces only work when objects physically touch each other.

Non-Contact Forces

These forces can act between objects without them touching each other

Weight

Is the force of gravity acting on a mass.

Mass

Is the amount of matter an object contains.

Satellite

An object which orbits a planet.

Solar Eclipse

The moon casts a shadow onto the Earth.This happens when the moon Earth and it moves in between the sun and The Earth.The moon blocks the light of the sun from reaching the Earth

Lunar Eclipse

The sun, Earth and Moon line up with Earth between the Sun and the Moon. Earth casts a shadow on the moon

Force

A push or a pull that acts on an object due to the interaction with another object

Contact Forces

A force where objects need to be touching for the force to have an effect.e.g. pushing a ball.

Non-Contact Forces

A force that can act over a distance.e.g. gravity.

Balanced Forces

When the total force in opposite directions are equal in magnitude. For example, with a thrust of 15 N and a frictional force of 15 N, the body experiences balanced forces.

Unbalanced Forces

Forces that are not equal in magnitude and may or may not act in the same direction.

Accuracy

A measure of how close something is to its true value.

Precision

A measure of how close measurements are to each other.

Resultant Force

The net force or the overall effect of all the forces acting on an object.

Unicellular

Organisms that are made of only one cell e.g. bacteria.

Multicellular

Organisms that are made of many cells e.g. humans.

Nucleus

Controls the cells activities because it contains DNA.

Cell membrane

Controls what enters and leaves the cell.

Cytoplasm

A jelly-like substance where reactions happen.

Cell Wall

Surrounds plant cells and provides strength and support.

Chloroplasts

Where photosynthesis take place to make food (glucose) for the plant and contain chlorophyll to absorb sunlight.

Vacuole

Contains a liquid that stores substances for the cell and keeps it rigid.

Hazard

Something that can cause harm

Risk

The harm that might happen to you or someone else

Precaution

What you do to prevent a hazard from causing harm.

Sperm Cell

The male reproductive cell. It is responsible for fertilising the egg cell from a female to create a baby.

Neuron

A specialised cell that carries electrical signals (called nerve impulses) around the body. Neurons are part of the nervous system, which includes the brain, spinal cord, and nerves

Leaf cell

Their function is to take in lots of sunlight (for photosynthesis to make food). Their structure helps them to do this as they have lots of chloroplasts.

Root hair cells

Their function is to take in lots of water. To help them to do this, their structure consists of a large surface area to take water in.

Tissue

A group of the same cells working together.

Organ

A group of tissues working together for the same function.

Organ System

A group of organs working together for the same function.

Solids

Regular pattern, touching, vibrate in place.

Liquids

Random arrangement, touching, move freely.

Gases

Random, not touching, move freely.

Diffusion

Movement of particles from high to low concentration. Occurs in liquids and gases, not solids. Faster at higher temperatures.

Independent Variable (IV)

You change.

Dependent Variable (DV)

You measure

Control Variables (CV)

You keep the same

Gas Pressure

Caused by particle collisions with container walls.

Density

mass ÷ volume

Kinetic Energy

Moving objects.

Gravitational potential energy

High-up objects

Elastic potential energy

Stretched/twisted/bent objects

Thermal energy

Hot objects

Chemical energy

Fuels and batteries

Heat

Thermal energy moving between stores (measured in watts)

Temperature

How hot/cold (in °C)

Thermal energy

Energy from particle motion (in joules)

Conductors

Allow heat flow easily (e.g. metals)

Insulators

Resist heat flow (e.g. non-metals)