Year 9 Science- Earth and Space

Lithosphere

Contains all of the Earth’s layers, the core, mantle, and crust

Hydrosphere

The sphere containing all the water, in any form, and anything linked to water.

Atmosphere

Contains all the gases that surround Earth

Biosphere

Everything on Earth that’s living.

Water cycle

Sunlight energy causes water in bodies of water to evaporate, converting it into water vapour. The water vapour rises into the atmosphere, condensing and cooling to form droplets of water around particles, which join to make clouds. When clouds get too heavy, droplets and ice crystals fall as precipitation. Some of the water soaks into the soil and is absorbed by plants, which release water vapour through transpiration.

Interaction between lithosphere and biosphere

Plants grow in soil, which is a part of the lithosphere. This provides them with essential nutrients and minerals, enabling them to grow.

Interactions between lithosphere and hydrosphere

Rivers in the hydrosphere run over the lithosphere, picking up sediments, soil and minerals from the river bed. These are deposited at the mouth of the river, becoming a part of the geosphere.

Interactions between lithosphere and atmosphere

Volcanic eruptions occur when magma in the Earth’s lithosphere is forced out of a volcano, releasing dust and ash particles into the atmosphere. Lots of these particles are then deposited back onto the lithosphere, while the remaining particles become a part of the atmosphere.

Interactions between hydrosphere and atmosphere

When water evaporates, it rises into the atmosphere where droplets condense around particles to form clouds. These clouds are also part of the atmosphere and block some of the ultraviolet radiation from the sun. When the clouds get too heavy, droplets fall as precipitation.

Interactions between hydrosphere and biosphere

Living things require water for survival, they consume water or use it in the process of photosynthesis.

Interactions between atmosphere and biosphere

All living animals respirate, and most plants photosynthesise. This circulation of gases contributes to the carbon cycle.

What are the levels of organisation in the biosphere

Organism, population, community, ecosystem, biosphere.

Describe the levels of organisation in the Biosphere

Organism: Single living individual

Population: A group of the same species in one area

Community: different populations interacting in one area

Ecosystem: Communities plus their environment

Biosphere: All living things

What are the five trophic levels and define each?

Producers: plants and algae that capture solar energy for photosynthesis

Primary Consumers: Herbivores that eat the producers

Secondary Consumers: Carnivores that eat the primary consumers

Tertiary Consumers: Top apex predators that eat primary and secondary consumers

Decomposers: fungi and bacteria that eat dead/decaying animals and recycle nutrients back into the system

What is biodiversity?

Biodiversity is the variety of living organisms across an ecosystem, including different species and genetic diversity.

Why is biodiversity important?

Biodiversity is important for ecosystem stability because all different organisms in an ecosystem rely on each other to support themselves and balance out consumerism. Biodiversity enables an ecosystem to be able to recover after disturbance.

What is photosynthesis?

Photosynthesis is the process which plants use sunlight energy to convert carbon dioxide from the atmosphere and water into glucose (chemical energy which is stored in plant bonds and fibres) and oxygen

What is cellular respiration

Cellular respiration is the process by which living organisms inhale oxygen and produce energy, causing them to exhale carbon dioxide as a byproduct and also produces water.

What are the worded equations for cellular respiration and photosynthesis (reactants → products)

Photosynthesis: carbon dioxide + water + sunlight → glucose + oxygen
Cellular respiration: oxygen + glucose → carbon dioxide + energy + water 

What is the ozone layer

The ozone layer is the thin layer of concentrated ozone (O₃) that is found in the stratosphere. It blocks most of the harmful ultraviolet rays from the sun, absorbing them and protecting living things from harm.

What is the greenhouse effect?

A natural process where the Earth’s atmosphere traps heat from the sun to increase the Earth’s average surface temperature.

What are greenhouse gases and give examples?

Greenhouse gases are gases that sit near the surface of the atmosphere and block most infrared radiation. They are required for the greenhouse effect. They include nitrous oxide, carbon dioxide, water vapour and methane.

What is the enhanced greenhouse effect and what causes it?

The enhanced greenhouse effect is the excess buildup of greenhouse gases, which amplifies the greenhouse effect, leading to increasingly warmer temperatures in the Earth’s atmosphere. This is due to human activities such as industry, burning fossil fuels, deforestation and transport.

What is the difference between climate and weather and give an example?

Climate is the long-term average conditions and weather patterns of a region, while weather is the fluctuating daily patterns in temperature, rainfall and wind in a specific place over a short period of time. For example, Cairns has a tropical and warm climate, while the weather on any day could be sunny or rainy.

What is evaporation

The transformation of liquid water into water vapour, caused by the sun’s energy heating up the surface of bodies of water.

What is condensation

The transformation of water vapour into liquid water, caused by the cooling of water vapour in the Earth’s atmosphere.

What is precipitation

The falling of water or ice back to the Earth’s surface due to gravity, as rain, snow, hail or sleet.

What is run-off

Excess water on the Earth’s surface, which flows over the ground into rivers and streams.

What is transpiration

The process by which plants absorb water from the soil and then release it as water vapour through their stoma into the atmosphere.

What is groundwater

Stored water below the Earth’s surface in bores or aquifers.

What is infiltration

Rainwater soaks into the ground and flows through soil and rock layers

What are ocean currents and how are they generated

Ocean currents are the continuous predictable movement of water around the globe. They are generated by differences in water temperature. Warmer, less dense water on the surface of the ocean near the equator moves towards the poles, cooling down and becoming denser. This water sinks to the bottom of the ocean and flows back to the equator, creating a circulating ocean current.

What effect does salinity have on ocean currents

Salinity affects ocean water density as higher saline water is denser, so it sinks, while lower saline water is less dense, so it rises.

What effect does melting sea ice have on salinity and how can this effect ocean currents?

Frozen sea ice has very low salinity. This means that when it melts, it causes the water around it to be less saline, which reduces its density. This can effect global ocean currents as it decreases the density of polar water, making it harder to sink to the bottom of the ocean, which can affect water movement around the globe and disrupt climates.

What is the carbon cycle

The carbon cycle is the continuous movement of carbon dioxide through the Earth’s spheres.

What is the purpose of the carbon cycle

The carbon cycle moves carbon atoms between the Earth’s atmosphere, oceans, land and living organisms. It is essential for life on Earth as it helps regulate Earth’s temperature and carbon dioxide levels.

What is the role of plants and photosynthesis in the carbon cycle

Plants absorb carbon dioxide through the atmosphere and through photosynthesis, together with sunlight energy and water, convert it into glucose, which is stored as chemical energy that is used to build the plant’s stem, leaf and root tissues. This carbon is stored in biomass and contributes to long-term carbon storage, helping regulate carbon dioxide levels in the atmosphere. This releases oxygen as a byproduct, increasing the amount of oxygen in the atmosphere and reducing carbon dioxide.

What is the role of respiration in the carbon cycle

Cellular respiration is the process by which animals and other organisms break down the bonds of glucose, combining it with inhaled oxygen to produce energy, which allows them to undergo daily processes. Cellular respiration produces water and carbon dioxide as byproducts. Carbon dioxide is exhaled and released into the atmosphere, maintaining a balance of carbon dioxide and oxygen in the atmosphere by decreasing oxygen and increasing carbon dioxide.

How does deforestation, decomposition and combustion affect the carbon cycle

Deforestation, decomposition and combustion are all processes that release carbon dioxide into the atmosphere, increasing carbon levels. These processes all involve living material and biomass. Due to the process of photosynthesis, carbon is stored in these materials as glucose. When the material is burnt, decomposed or deforested, these carbon stores are exposed, releasing carbon dioxide gas into the atmosphere, speeding up the carbon cycle and contributing to climate change.

What is the difference between a carbon source and a carbon sink

A carbon source is a process that releases carbon dioxide into the atmosphere, increasing carbon levels and contributing to the enhanced greenhouse effect and global warming. A carbon sink, however, absorbs carbon dioxide from the atmosphere and stores it, decreasing carbon dioxide levels in the atmosphere and slowing down climate change.

What is solar radiation

Solar radiation is the electromagnetic radiation emitted from the sun. It includes ultraviolet radiation, visible light and infrared radiation

What is ultraviolet radiation

Ultraviolet radiation is a type of radiation emitted from the sun. It is high in energy and has a shorter wavelength, and causes harm to living things on Earth. Most of the ultraviolet radiation from the sun is blocked by the ozone layer, including all of UVC and most of UVB

What is terrestrial radiation

Terrestrial radiation is the outgoing infrared heat energy emitted from the Earth’s surface after absorbing sunlight.

What is infrared radiation

Infrared radiation has a shorter wavelength than UV radiation and is less penetrable through the atmosphere, as most of it is absorbed by clouds and greenhouse gases. Only small amounts of infrared radiation can escape Earth’s atmosphere, meaning most of it is trapped close to the surface through the greenhouse effect, keeping the Earth’s average surface temperature at a sustainable temperature.

What are the three forms of heat transfer

Conduction, convection and radiation

What is conduction + example

Heat transfer through solid objects, for example, hot rocks in the lithosphere transferring to plants growing on the rocks (particles don’t move, just touch through direct contact) 

What is convection + example

Heat transfer through moving liquids or gases, for example, hot air rising and cool air sinking in the atmosphere (particles move around to touch)

What is radiation (and an example)

Heat transfer by electromagnetic waves, for example, ultraviolet radiation from the sun heating Earth’s surface.

What is albedo

Albedo is the power and ability of an object or surface to reflect sunlight. Darker objects have a low albedo, as most of the sunlight is absorbed, while lighter, or reflective surfaces have a high albedo, meaning most of the sunlight is reflected. (another word for reflective power)

How does excessive albedo influence the enhanced greenhouse effect and global warming?

The atmosphere reflects a certain amount of the sunlight that travels to Earth. As well as this, ice such as ocean ice and polar caps has a very high albedo, meaning it reflects a lot of the sunlight into space, away from the earth. Global warming causes large ice masses to melt, meaning that less sunlight is reflected from the earth into space, and more is absorbed, so temperatures rise, leading to further ice loss and increased temperatures. Melted ice leads to sea levels rising, so more of the Earth is covered by water and less by land. The ocean has a very low albedo compared to land and other materials on Earth, so it absorbs most of the sunlight transferred onto it. This causes oceans to heat up, producing more terrestrial radiation, causing atmospheric temperatures to increase exponentially, contributing to the enhanced greenhouse effect.

What are fossil fuels, how are they created and provide examples?

Fossil fuels are non-renewable energy sources that are created over millions of years through the fossilisation of ancient plants and animal remains. For example, coal and oil.

What are the four greenhouse gases?

Nitrous oxide, carbon dioxide, methane and water vapour