Year 9 Science- Earth and Space

What is the lithosphere?

The sphere containing all of the Earth’s layers, the core, mantle, and crust

What is the hydrosphere

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

What is the atmosphere?

The sphere containing all the gases that surround the Earth, mostly nitrogen and oxygen.

What is the biosphere?

The sphere that holds and supports life, including all living things.

Explain the 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 back to earth, filling bodies of water and rivers that run off into the ocean. 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 liquid rock (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 in another area, while the remaining particles become a part of the atmosphere.

Interactions between hydrosphere and atmosphere

When water evaporates from seas, lakes and oceans, 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 consume water or use it in the process of photosynthesis. Water is also a part of the surrounding environment in which organisms and plants live. Organisms can change the water in the hydrosphere’s chemical composition through respiration and photosynthesis.

Interactions between atmosphere and biosphere

All living animals respirate, a process which involves inhaling oxygen from the atmosphere and exhaling carbon dioxide. Plants and some organisms in the biosphere complete the opposite process of photosynthesis, taking in carbon dioxide and releasing oxygen back into the atmosphere. This circulation of gases contributes to the carbon cycle.

What are the five levels of organisation in the biosphere

Organism, population, community, ecosystem, biosphere.

Describe the levels of organisation in the Biosphere

• The organism is a single living being. 

• A population is a group of the same species of organism living in the same area. 

• A community is a larger group consisting of many different species living in the same area. 

• An ecosystem is all the communities of organisms in an area, as well as all the abiotic components of an environment like water, soil and air, which interact with living things. 

• The biosphere is all the ecosystems on earth, all life and the environments that support it.

What is the first level of the food chain

The first level is the sun. The sun provides energy to all living things on Earth, keeping them alive.

What is the second level of the food chain

The second level is the producers. These are the plants and some organisms that are able to turn sunlight into chemical energy through photosynthesis.

What is the third level of the food chain

The third level is the primary consumers. These animals are mainly herbivores, meaning they only consume plants, the producers. By consuming them, the energy stored is transferred to the primary consumers.

What is the forth level of the food chain?

The fourth level is the secondary consumers. These are omnivores and carnivores who consume primary consumers, leading to energy transfer.

What is the fifth level of the food chain

The fifth level is the tertiary consumers or apex predators. These are the top animals in the food chain, which mainly consume secondary consumers. The energy is transferred to this group.

What role do decomposers play in the food chain

Decomposers decompose deceased animals and plants, leading to the transfer of energy to these organisms

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 break down glucose to use as energy. This produces energy, causes them to exhale carbon dioxide as a byproduct and also produces water.

What are the five parts of the atmosphere

Troposphere, stratosphere, mesosphere, thermosphere and exosphere

Describe the parts of the atmosphere

• Troposphere: The lowest layer, which is where all of Earth’s weather occurs. 

• Stratosphere: Contains the Ozone layer, which absorbs most of the harmful ultraviolet radiation from the sun.

• Mesosphere: Layer above the stratosphere, in which most meteors burn up.

• Thermosphere: The layer in which satellites orbit, and auroras occur

• Exosphere: The final layer of the atmosphere, which thins out gradually until it is space.

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 keep the planet warm enough for life.

How does the greenhouse effect work?

The greenhouse effect works by trapping heat close to the Earth’s surface to stop it from escaping. This keeps the surface of the Earth warm enough to support life. This effect occurs when ultraviolet radiation from the sun enters Earth’s atmosphere and is absorbed by the oceans and land. This heat radiates back as terrestrial radiation, or infrared radiation, which has a longer wavelength than ultraviolet, meaning it doesn’t travel as fast. Because of this, not much of it escapes into space, so most is trapped inside the atmosphere by greenhouse gases.

What are greenhouse gases

Greenhouse gases are mostly carbon-based gases that trap heat inside the Earth’s atmosphere, keeping the planet and all living things on it warm. The four main types of greenhouse gas are Carbon dioxide, methane, nitrous oxide and water vapour. While naturally occurring, excess greenhouse gases are produced from human activity, such as burning fossil fuels and deforestation.

What is the enhanced greenhouse effect

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, which produce extra unnecessary greenhouse gases like methane and carbon dioxide. These extra gases are released into the atmosphere, strengthening the greenhouse effect.

What is the difference between climate and weather

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

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, 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 process of photosynthesis 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.

What are two ways carbon is removed from the atmosphere

• Photosynthesis: Photosynthesis is the process by which plants remove carbon dioxide from the atmosphere, and together with water and sunlight energy, convert it into glucose, as well as oxygen, which is released into the atmosphere.

• Ocean absorption. Carbon dioxide is absorbed from the atmosphere into the ocean, where it dissolves to form carbonic acid, used by marine organisms to build shells or skeletons.

What are two ways carbon is returned to the atmosphere

• Cellular respiration: Cellular respiration is the process by which living organisms inhale oxygen and break down glucose to form energy, with water and carbon dioxide as a byproduct. The carbon dioxide is released into the atmosphere.

• Combustion: Burning fossil fuels, biomass, or other materials releases carbon from their bonds and tissues that had been stored as glucose through photosynthesis. The carbon dioxide is released into the atmosphere

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 ultraviolet 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 surface of Earth warm.

What are the three forms of heat transfer

Conduction, convection and radiation

What is conduction (and an example)

Heat transfer through solid objects, for example, hot rocks in the lithosphere transferring to plants growing on the rocks

What is convection (and an example)

Heat transfer through moving liquids or gases, for example, hot air rising and cool air sinking in the atmosphere

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.

How does albedo influence the greenhouse effect

Albedo influences the greenhouse effect because the atmosphere reflects a certain amount of the sunlight that travels to Earth. Ocean ice and polar caps have a very high albedo, meaning they reflect most of the sunlight that hits them into space, away from the Earth. Global warming causes large ice masses to melt, resulting in less sunlight 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.