Semester 1 Exam 2021

Question 1

Identify and describe the layers of the Earth in order and their pressure, temperature, and composition.

Answer 1

Inner core, outer core, mantle and crust.

Question 2

Describe how and why we use scales to create models.

Answer 2

A

Question 3

Describe how fossil evidence supports continental drift theory.

Answer 3

Fossils of similar types of plants and animals in rocks of a similar age have been found on the shores of different continents, suggesting that the continents were once joined.

Question 4

Identify evidence for continental drift theory from the ocean floor.

Answer 4

A

Question 5

Identify what natural phenomena the theory of plate tectonics helps explain.

Answer 5

The theory of plate tectonics helps to explain earthquakes. When these plates move around, they collide, move apart or slide past each other. This can cause vibrations known as earthquakes and can also create conditions that cause volcanoes to form. Tsunamis are also caused as a result of earthquakes.

Question 6

Summarize the differences between convergent, divergent and transform boundaries.

Answer 6

Divergent boundaries
Where new crust is generated as the plates pull away from each other.
Convergent boundaries
Where crust is destroyed as one plate dives under another.
Transform boundaries
Where crust is neither produced nor destroyed as the plates slide horizontally past each other.

Divergent can cause seafloor spreading

Convergent causes earthquakes and volcanoes.

Transform causes earthquakes.

Question 7

Why do tectonic plates move?

Answer 7

A

Question 8

Describe how earthquakes and volcanoes relate to tectonic plate boundaries.

Answer 8

As plates move, they get stuck in places, and enormous amounts of energy build up. When the plates finally get unstuck and move past each other, the energy is released in the form of earthquakes.

Volcanoes form when one tectonic plate moves under another.

Question 9

Explain the difference between the central nervous system and the peripheral nervous system.

Answer 9

The central nervous system consists of the brain and the spine and the peripheral nervous system are the nerves that connect the central nervous system to the rest of the body.

Question 10

Identify the main features of neurons.

Answer 10

Dendrites, Axon and a Cell Body or Soma

Question 11

Distinguish between different types of receptors.

Answer 11

A

Question 12

Analyse stimulus-response pathways.

Answer 12

A

Question 13

Describe what hormones are and the role they play in our bodies.

Answer 13

A

Question 14

Identify some of the main glands in the endocrine system and their targets.

Answer 14

A

Question 15

Describe what homeostasis is.

Answer 15

Homeostasis is the ability or tendency to maintain internal stability in an organism to compensate for environmental changes. An example of homeostasis is the human body keeping an average temperature of 37 degrees.

Question 16

Apply the concept of homeostasis to the control of blood glucose levels.

Answer 16

For example, when blood sugar is increased storing the sugar in the liver will return blood sugar levels back to normal and this is an example of homeostasis where the body attempts to keep internal stability by keeping blood sugar levels stable and moderated.

If blood sugar levels were to fall as well, which is the stimulus this would cause the pancreas to release glucagon and the liver would break down glycogen and release glucose.

Question 17

Define what an ecosystem is.

Answer 17

An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting with each other and their environment.
E.g. desert, rainforest, or ocean.

Question 18

Describe how biotic and abiotic factors interact in ecosystems.

Answer 18

A

Question 19

Identify and describe predator-prey relationships.

Answer 19

A

Question 20

Explain why organisms compete for resources.

Answer 20

Organisms compete for resources because sometimes resources are limited, there may not be enough resources to support all the organisms in a given environment causing them to compete for the resources.

Question 21

Compare the main types of symbiosis.

Answer 21

Parasitic - where one species benefits and the other species is harmed
Mutualistic - where both species benefit
Commensalism - where one of the organisms greatly benefits but the other is not helped but is not harmed o damaged from the relationship

Question 22

Describe how energy is transferred through a food chain.

Answer 22

A

Question 23

Explain why energy is lost in each step of the food chain.

Answer 23

A

Question 24

Describe how matter cycles through an ecosystem.

Answer 24

A

Question 25

Identify benefits of healthy ecosystems for humans.

Answer 25

A

Question 26

Explain how biodiversity helps protect ecosystems.

Answer 26

Because if one species dies out, there are still other species for the predators to feed on. And that also means that the predator’s don’t have one prey, because in an ecosystem with low biodiversity, one species dying out can start a catalyst of events because the predators of the species may not have food because they were only able to feed on that species because of the low biodiversity and this causes the predators to die on, and then the predators of the predators to die and so on. In a species with high biodiversity, this problem wouldn’t occur, because there would be a variety of species for predators to prey on and continue up the food chain.

Question 27

How do humans impact ecosystems?

Answer 27

A

Question 28

What is a detrivore?

Answer 28

Someone that eats dead matter.