Year 8 Science Term 2 Test

Abundance

The number of organisms of one species within a habitat.

Distribution

The location or arrangement of the species within a habitat.

Community

All of the organisms living in one habitat that interact with abiotic factors.

neutral atom

A(n) ________ (any in the periodic table) has equal numbers of protons an electrons.

Neutrons

________ have a mass of 1.

Producers

________: Organisms that use photosynthesis to make their own food from the suns energy.

Electrons

________ have a mass of 1 /1840.

Photosynthesis

________ occurs on the leaves of the plant.

Protons

________ have a mass of 1.

Compounds

________ contain 2 or more types of atoms that are chemically bonded in a fixed ratio.

molecules

All compounds are ________, but not all ________ are compounds.

Elements

________ are a sample of matter containing only 1 type of atom.

Atoms

________ are mostly comprised of empty space.

trophic levels

The ________ represent the amount of energy that an animal gains from eating prey, depending on how many animals the prey ate and so on.

electrical attraction

The ________ between the nucleus and the electrons keeps them orbiting the nucleus.

Metals

________ are elements that conduct heat and electricity, are generally solid at room temperature, have a high melting point, are Malleable (can beat into different shapes), are ductile (can turn into wire), and are shiny when polished.

Non metals

________ are elements that dont conduct heat and electricity well, melt and turn into gasses easily, are brittle, look dull, glassy and often coloured.

Biotic factors

________ are classified as living or once-living.

Abiotic factors

________ are classified as non- living.

Biomass

________ is the dry mass of the organisms at that trophic level.

Parasitic relationship

________: One organism hinders while the other thrives.

Food chains

________ and webs show the direction of energy flow in an ecosystem.

Photosynthesis

________ is the process carried out by plants to produce food.

Protons

________ have a positive electrical charge.

Electrons

________ have a negative electrical charge.

Molecules

________ contain 2 or more atoms that are chemically bonded in a fixed ratio.

Atoms

________ are the smallest part of a chemical element that can exist, they are the building blocks of matter.

The chemical equation for photosynthesis is

Carbon Dioxide (CO2) + Water (H2O) → [Sunlight and Chlorophyll]→ Glucose (C6H12O6) + Oxygen (O2)

Roots Purpose

Roots anchor the plant and help the plant to obtain water and minerals from the soil

Roots Structure

The main root; lateral roots, which spring off the main root; the root hairs, which maximise surface area to uptake more water and minerals

Stems Purpose

The stem holds up the plant and is used like a conveyor belt to transfer nutrients around the plant

Stems Structure

Xylem, which transfers water and minerals upwards; Phloem, which transfers sugars around the plant (translocation) in any direction

Xylem and phloem cell structure

Xylem cells are made of lignin, which is a protective outer layer; Phloem cells are made of sieve cells and companion cells.

Leaves Purpose

The leaves create the plants food with photosynthesis and are also needed for transpiration

Producers

Organisms that use photosynthesis to make their own food from the suns energy

Consumers

An organism that relies on other organisms for its food

Decomposers

An organism that breaks down organic matter and releases the energy back into the ecosystem

Predator

An animal that hunts for its food

Prey

An animal hunted for food

Herbivore

An animal that only eats plants

Carnivore

An animal that only eats meat

Omnivore

An animal that eats both meat and plants

Detritivore

An organism that feeds on organic material

Parasitic relationship

One organism hinders while the other thrives

Symbiotic relationship

Both organisms benefit

Predator-prey relationship

One is the "hunter", and one is the "hunted"

An atom comprises three types of particles

protons, neutrons and electrons

Population

A group of the same species living in the same place simultaneously.

Species

Organisms with similar structures that mate to produce fertile offspring.

Habitats

_______ are where a population lives.

Neiche

The role and position of a species in an ecosystem.

Habitat

The place where a population lives.

Reactants

The ______ are written on the left side of the arrow.

Products

The ______ are written on the right hand side of the arrow.