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Science gr9 exam Flashcards

1
Q

In what way does the presence of an atmosphere enhance conditions for life on Earth

A

It blocks solar radiation, moderates surface temperature.

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2
Q

Define each of the following terms: lithosphere, atmosphere, hydrosphere and biosphere

A

lithosphere- Rocky outer shell

atmosphere- Layer of gas that protects
life

hydrosphere- All water on, above and below earths surface

biosphere- All areas on earth where life is found

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3
Q

Describe the ways in which earths spheres overlap each other

A

The atmosphere protects the biosphere in the hydrosphere by stopping the radiation and heat that would kill all the fish in the hydrosphere

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4
Q

Why is the biosphere so fragile

A

The biosphere is fragile because all the conditions of life have to be met

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5
Q

What is the definition of the Gaia Hypothesis

A

Its the theory that earth acts like a living organism that responds to the changes in its environment

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6
Q

Does a community include abiotic features

A

Yes a community needs sunlight, water, temperature and soil to survive

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7
Q

which of the following are considered an ecosystem? Backyard pond, tree, all the cats in your neighbourhood, school yard, vase of cut flowers, potted plant and digestive system

A

Backyard pond, tree, school yard, vase of cut flowers, potted plant and digestive system

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8
Q

How much energy reaching earth is absorbed and converted to chemical energy by the process of photosynthesis? Where does the other energy go?

A

70% is absorbed by the earth as heat
30% is reflected back into space
les than 1% is absorbed using photosynthesis

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9
Q

What energy rich substance is produced by green plants during photosynthesis

A

Glucose

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10
Q

Explain how you know plants contain energy-rich substances?

A

Plants contain chlorophyll that captures light and preforms photosynthesis

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11
Q

How are photosynthesis and cellular respiration related?

A

Photosynthesis and cellular respiration are complimentary: they both need each other and they both create energy

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12
Q

What is meant by the term ecological niche?

A

The function a species serves in a ecosystem

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13
Q

What is the difference between food chains and food webs?

A

Food chains are one animal eats another and food webs are made up of multiple food chains

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14
Q

As you go up from one trophic level to the next, the amount of available energy decreases? Why?

A

The energy gets absorbed by the animal that ate the other animal

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15
Q

What trophic level contains the greatest biomass

A

Plants have the most biomass because they are producers

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16
Q

Why are photosynthesis and cellular respiration considered opposites?

A

They are considered opposites because the final product of photosynthesis is glucose and cellular respiration needs glucose to get started

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17
Q

Are green plants necessary in all ecosystems or not?

A

They are because without them the earth would not exist

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18
Q

What are three ways that humans have negatively impacted ecosystems?

A

Deforestation
climate change
overhunting

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19
Q

Name one idea that many indigenous peoples have regarding ensuring sustainability

A

Laws of nature

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20
Q

What is meant by the term cultural services

A

It’s the recreational, aesthetic and spiritual experiences we receive when we interact with our surroundings

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21
Q

Name two ecosystem products

A

Wood
seafood

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22
Q

what other services do ecosystems provide?

A

Protecting us form physical threats, acting like sponges to absorb water and acting as a windbreak.

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23
Q

What does it mean by an ecosystem having a monetary value?

A

It means that the dollar value of cleaning the air and water, moderating climate and providing paper fiver, medicines and other products is high.

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24
Q

what is meant by equilibrium

A

equilibrium is the state of an ecosystem with relatively constant conditions over a period of time

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25
what is one example of where you see equilibrium in nature
A forest
26
What is the difference between primary and secondary succession?
Primary succession is when there is no life and secondary succession is when there is little life
27
Where would biodiversity be the greatest?
Biodiversity would be the greatest at the equator
28
What is it called when a species no longer exist in a certain area?
Extirpated
29
What is it called when a species is facing imminent extirpation or extinction?
Endangered
30
What are the three main ways that humans can control invasive species?
Chemical Mechanical Biological
31
What is done when mechanical control is used?
Humains build or remove physical barriers, cut down, burn or remove plant and hunt or trap animals
32
What is acid rain?
It is precipitation that contains high levels of nitric and sulphuric acids
33
How is acid rain caused?
It is caused by the burning of fossil fuels and when burning fossil fuels sulfur dioxide and nitrogen oxides are released into the atmosphere and react with oxygen and other substances to create acid
34
What are the two main gasses that cause acid rain?
Sulfer dioxide and nitrogen oxides
35
Name three areas acid precipitation is affecting our ecosystems
Makes aquatic ecosystems to acidic damages soil damages trees
36
How can we reduce the acid rain problem
We can designing cleaner power plants. and using fewer fossil fuels
37
Name four ways to deal with an accidental oil spill
Skimming burning Dispersion bioremediation
38
What is the greenhouse effect and how is it caused?
It is the process where earths average temperature is increasing. It's caused bu the atmosphere trapping heat in that normally bounces back into space
39
How can we reduce the effects of the greenhouse effect
We can burn less fossil fuels, stop deforestation and don't use fertilizers
40
Name three ways that first are harvested
clearcutting shelterwood cutting selective cutting
41
What is meant by the term Agroecosystems?
Have more uniform abiotic features, have lower biodiversity and are more intensively used by humans, require humans to maintain them
42
What is meant by the term monocultures?
Only grow one species of organism
43
How are pesticides harmful?
They can harm a non intended species, can get into our water and food and the toxins can build up in the ecosystem over tine
44
What is meant by broad-spectrum pesticides?
They're pesticides that are toxic to a wide variety if species
45
Explain the concept of bioamplification
It is a concept that suggest that poison gets passed down from animal to animal in the food chain
46
What is the difference between a element and a compound?
A element is made up of only one kind of atom and a compound is made up of multiple atoms
47
How are atomic elements named?
Atomic elements are represented by the 2 letters generally the first 2 in their name
48
Where are the metals, non-metals and metalloids located in the periodic table
The metals are located on the left, the metalloids have a staircase on the right and non-metals are located on the far right
49
What do non-metals generally look like?
Dull and non-reflective
50
What do metalloids generally look like?
Shiny and reflective
51
Name some properties of metals
Good conductors Shiny Tough and strong
52
What are heavy metals?
They are a group of metallic elements
53
What is the problem with them? Give an example of a heavy metal
The problem with them is that they are dense and toxic. Some examples of them are Pb, Hg and Cd
54
What is a theory?
A theory is an expression of our best understanding of a phenomenon
55
What did Aristotle contribute to the development of the atom?
The four element idea
56
What did Democritus contribute to the development of the atom?
All things are made up of atoms
57
What did Dalton contribute to the development of the atom?
The billard ball model
58
What did Thomson contribute to the development of the atom?
That atoms contain electrons
59
What did Rutherford contribute to the development of the atom?
The nucleus
60
What did Chadwick contribute to the development of the atom?
Discovered neutrons
61
Explain how different colours of light are produced
When energy is given to an atom it gets put into the excited state. When it goes back down to ground state it releases the energy it absorbed in the form of light or colour
62
Define atomic number
The number of the element on the periodic table
63
Define atomic mass
How much mass the element has
64

Gr9 (3 decks)

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