How did Earth form? What are some reasons it could not support life?

Earth formed from the collision of large meteors in space that eventually cooled and orbited the sun.

Earth could not initially support life because the environment was too hostile. The surface was molten, the atmosphere was filled with toxic gases and there was no ozone layer to protect earth from the harmful rays of the sun.

Where did Earth’s earliest life forms appear?

The earliest life forms appeared in the ocean.

ocean

Why were cyanobacteria important in the evolution of life on earth?

Cyanobacteria made their own food through photosynthesis. This process releases oxygen gas into the atmosphere. Cyanobacteria changed the composition of the atmosphere from toxic to oxygen rich.

What is the hydrosphere? Where is most of the ____ in the hydrosphere found

The hydrosphere contains all the water found on earth.

Most of the water in the hydrosphere is found in oceans.

What are the major parts of the water cycle?

The major parts of the water cycle include evaporation, condensation, transpiration, & precipitation. (Run off is also a part of the water cycle)

Sketch a diagram of the carbon cycle

What are some positive and negative impacts of the industrial revolution?

• Positive impacts of the industrial revolution include an improved quality of life for humans.

• Negative impacts of the industrial revolution include habitat loss for animals and increased pollution into the environment.

What are some natural resources?

• Some natural resources include water, wood, natural gas and fossil fuels.

What is the scientific method? Describe the steps.

• The scientific method is a series of steps taken to answer a question. An observation of the world is made leading to a question. A hypothesis or possible scientific answer to that question is proposed. An experiment is designed to test the hypothesis, the experimental data is analyzed to see what it all means. A conclusion is written explaining if the hypothesis is supported or rejected. A scientists should then communicate the process.

What does the law of conservation of matter state?

• The law of conservation of matter states that matter cannot be created or destroyed.

What is a food chain? Why is it important to study?

• The food chain shows the relationship between organisms and how energy is transferred from one to another as they are eaten.

• It is important to study food chains because they illustrate the connections between organisms. If one organism is lost you can see that the food chain becomes disrupted.

How are weather and climate different?

• Weather is different from climate because it is the moment by moment conditions where as climate is the overall average conditions of an area.

What are the layers of the earth?

• The layers of the earth are core, mantle and crust.

What is the difference between primary and secondary succession

• In primary succession life forms in an area where there was no life but in secondary succession life forms again in an area usually after some environmental disturbance like a fire, a flood or after a lake has dried up.

Name some biotic and abiotic factors.

• Abiotic factors include soil, water, rocks, air, etc.

• Biotic factors include plants, animals, fungi, etc.

What is biodiversity?

• Biodiversity is the variety of life on earth.

What did Charles Darwin propose

• Darwin proposed the theory of natural selection. He noticed the finches on the Galapagos islands had different beak shapes. He proposed that each finch had a common ancestor but evolved different looks as it adapted to its environment.

Why is it so hard for scientists to determine the number of species on Earth?

• It is hard for scientists to determine the number of species on Earth because the planet is so large, species evolve and become extinct, it is costly to research and places we can reach are limited (ex: deep sea trenches).

What are 3 types of adaptations prey have evolved for survival? Describe each.

• Camoflauge – coloration to blend into your environment

• Mimicry – disguised to look like something else

• Warning coloration – a harmless organism looking like something harmful and poisonous

Explain the relationship between evolution and the ecosystem.

• The changes in the ecosystem are the driving force for evolution. Organisms that can survive (have a niche) in their environment will reproduce passing their traits (adaptations) to their offspring. As the ecosystem changes the species population will change.

How do animals help spread seeds? Give an example

• Animals help spread seeds through seed dispersal.

• Example: Animals ingest seeds in one area then lay their fecal matter or waste containing the seeds in another area.

Why is it important to recycle?

• Many resources on earth are limited and we may eventually run out.

• Recycling reduces the amount of waste put in dumps and into the environment.

Give an example of a key stone species. Explain why it is so important.

• The beaver is a key stone species. It is so important because the dams it builds creates ecosystems for different organisms to live. Key stone species is responsible for increasing species diversity in an area.

Why does the loss of one species affect other species?

• All organisms are linked in one way or the other. Some rely on others for food, survival, shelter or even reproduction. Organisms are linked in the food web and if one part is missing it affects all in the web.

Give an example of how 2 different species depend on each other?

• Bees depend on flowers for nectar and flowers depend on bees for reproduction.

Explain what “survival by association” means. Give an example

• Survival by association means that two or more organisms depend on a relationship between each other to survive. (mutualism, commensalism and parasitism)

• Example: Clownfish and the sea anemone, anemone provides the clownfish with protection.

How does speciation contribute to evolution?

• Speciation is the separation of a population. This separation sometimes leads to the development of 2 new species as the populations become adapted to their new environments.

What is a mutation and how does it play a role in evolution?

• A mutation is a sudden change, in this case a sudden change in DNA or the genetic material of an organism. If these mutations give an organism a better chance for survival then the organism may pass this mutation on to its offspring.

Why might doctors be concerned about decreasing biodiversity?

• Doctors might be concerned with the decreasing biodiversity because it decreases chances of survival. We depend on different species to provide us with medicines and resources for keeping us healthy. Also, we learn a lot from other organisms and this information too can be used to heal the sick.

What are some ways plants and animals keep water cleaner?

• Plants help keep water cleaner because its roots prevent soil from running off into the water. They prevent pollutants from entering bodies of water.

• Animals like the oyster are filter feeders, so as they take in food and water they also take in dirt and pollutants.