life sciences

Question 1

Ecology

Answer 1

The study of earth, the interaction of organisms with their physical environment and with one another.

Question 2

Biosphere

Answer 2

The part of the earth and its atmosphere in which living organisms exist or that is capable of supporting life.

Question 3

Hydrosphere

Answer 3

All the waters and watery parts on the earth’s surface such as the ocean, rivers, dams, and lakes.

Question 4

Atmosphere

Answer 4

The envelope of gases that surround the earth in which living organisms can breathe.

Question 5

Lithosphere

Answer 5

The rock and crust surface that covers the earth. The rocks, soil, and mountains where life occurs.

Question 6

Abiotic

Answer 6

All of the non-living components of the biosphere such as temperature, wind, water, soil, etc.

Question 7

Biotic

Answer 7

The living organisms that make up an ecosystem. These components are co-dependent on one other and influence one another. Together they make up an ecosystem.

Question 8

TRUE/FALSE: The atmosphere causes 29% of the sun’s radiation to be reflected back into space and absorbs 20% of it.

Answer 8

TRUE

Question 9

Nitrogen

Answer 9

79%

Question 10

Oxygen

Answer 10

21%

Question 11

Carbon Dioxide

Answer 11

0.04%

Question 12

Because cooler air is denser than warm air it descends. Warm air is less dense and thus rises. As warmer air rises, air pressure increases and the air expands.

This expansion causes the warm air to cool off and it loses moisture in the form of rain and snow (cool air has less moisture than warm air). The earth is heated in various patterns and thus air rises and falls in various patterns.

These heating patterns together with the earth’s rotation are responsible for the wind and rainfall patterns.

Factors that influence rainfall:

1. The gradient (slope)
2. The rain-shadow.
3. The height above sea level (altitude)
4. Global positioning.

(IS THIS STATEMENT CORRECT?!!)

Answer 12

Yes, it is correct.

Question 13

Physiographic Factors

TRUE/FALSE: Factors such as height above sea level (altitude) and latitude influence the outer space. When the space is influenced then aliens cannot invade us.

Answer 13

FALSE. Physiographic factors such as height above sea level (altitude) and latitude influence the climate of an area. When the climate is influenced then the plants and animals in that area are also affected.

Question 14

There are three main types of soil

? - Consists of particles that generally larger, has poor water retention capacity and has varying temperatures. It is well aerated but contains little humus (decaying organic matter).
? - Consists of a mixture of soil particle sizes and has a good water retention capacity. It is well aerated and is rich in humus. Soil organisms prefer loam because of its higher humus content. It is ideal for use in agricultural activities.
? - Consists of very small particles and has a high water retention capacity. It is poorly aerated and has poor humus content.

Answer 14

(sandy soil, loam, and clay soil)

Question 15

There are three types of soil water. Name them all along with their definitions.

Answer 15

Hygroscopic water: Water molecules cling to soil particles and are not available to plants.
Capillary water: Water molecules are between soil particles and can be adsorbed by plants.
Seepage water (gravitational water): This water moves from the upper soil layers, where it is available to plants, to the deeper layers of the soil where the plant roots can’t reach it. This water is also known as borehole water.

Question 16

The pH of soil - The alkalinity or acidity of the soil is important, especially to ______.

Alkaline soil, also known as _________ soil, is found in areas with ___ rainfall. The low rainfall allows for an _____________________ in the soil which is responsible for the alkaline pH.
Acidic soil is found in areas with ____ rainfall. The high rainfall washes salts from the soil and replaces them with ___________________, thus resulting in a low pH.
Most plants prefer neutral or _________________ soils.

(FILL IN THE BLANK.)

Answer 16

The pH of soil - The alkalinity or acidity of the soil is important, especially to plants.

Alkaline soil, also known as brackish soil, is found in areas with low rainfall. The low rainfall allows for an accumulation of salts in the soil which is responsible for the alkaline pH.
Acidic soil is found in areas with high rainfall. The high rainfall washes salts from the soil and replaces them with hydrogen ions (H+), thus resulting in a low pH.
Most plants prefer neutral or slightly alkaline soils.

Question 17

Producers - Green chlorophyll-containing plants are classified as _________. These plants are ___________ because they make energy-containing organic molecules from inorganic raw material by using sunlight as their energy source during ______________.

(FILL IN THE BLANK.)

Answer 17

Producers - Green chlorophyll-containing plants are classified as producers. These plants are autotrophic because they make energy-containing organic molecules from inorganic raw material by using sunlight as their energy source during photosynthesis.

Question 18

TRUE/FALSE: Consumers - These organisms are dependent on producers for nutrients and are thus classified as heterotrophic.

Herbivores are primary consumers as they eat the producers (plants) directly.
Carnivores are secondary (eat primary consumers) or tertiary consumers (eat primary and secondary consumers).
Decomposers decompose dead organic matter and fit into all levels of biotic factors.
Predators hunt for their prey, kill and eat it.
Scavengers feed off of carcasses e.g. vultures.
Opportunistic feeders eat anything they can find e.g. baboons.

Answer 18

TRUE.

Question 19

TRUE/FALSE: Food Chain - is a diagram of the flow of animals from producers to consumers and then reducers. Food chains can be complicated and have more than one lines. These complicated food chains are called food contraption.

Answer 19

FALSE. Food Chain - is a diagram of the flow of energy from producers to consumers and then decomposers. Food chains can be complicated and have more than one pathway. These complicated food chains are called food webs.