humans and the environment

Question 1

ecology

Answer 1

the study of the relationships among living organisms and their physical environment

Question 2

species

Answer 2

a group of organisms that can reproduce with one another in nature and produce fertile offspring

Question 3

population

Answer 3

A group of individuals of the same species within a community

Question 4

community

Answer 4

an interacting group of various species in a shared/ common location

Question 5

ecosystem

Answer 5

a geographic area where plants, animals, and other organisms, as well as weather and landscape, work together to form a bubble of life

Question 6

biomes

Answer 6

an area classified according to the species that live in that location

Question 7

biodiversity

Answer 7

the variety of all living things and their interactions

Question 8

abiotic factors in an ecosystem and their effects on the community

Answer 8

refers to the non-living components of an ecosystem. They include physical and chemical factors such as temperature, light, water availability, soil composition, air quality, humidity, pH

directly influence the distribution, abundance, and behaviour of organisms within the community

E.G: temperature affects the metabolic rates and physiological functions of organisms, while water availability determines the productivity and survival of plants and animals

Question 9

biotic factors in an ecosystem and their effects on the community

Answer 9

refers to the living components of an ecosystem. They include all the organisms present, including plants, animals, fungi, bacteria, and other microorganisms

they play roles as producers, consumers, and decomposers, influencing energy flow, nutrient cycling, and food webs

Question 10

temperature, rainfall and vegetation of tundra

Answer 10

extremely cold temperatures, low precipitation, and unique vegetation adapted to withstand the harsh environment

Question 11

temperature, rainfall and vegetation of coniferous forest

Answer 11

cold temperatures, moderate to high levels of precipitation, and cone-bearing evergreen trees, such as pine, spruce, fir, and cedar

Question 12

temperature, rainfall and vegetation of broadleaf forest

Answer 12

distinct seasons, (warm summers and cold winters), moderate to high levels of annual precipitation, and a diverse range of trees that shed their leaves during the winter season (maple, oak, birch)

Question 13

temperature, rainfall and vegetation of tropical forest

Answer 13

high temperatures, extremely high precipitation levels, dense, lush vegetation (extremely biologically diverse ecosystem)

Question 14

temperature, rainfall and vegetation of grassland

Answer 14

warm temperatures. Depends on the grassland, but they can achieve either low or moderate levels of rainfall, and are dominated by species of grasses and herbaceous plants

Question 15

temperature, rainfall and vegetation of desert

Answer 15

during the day its extremely warm but during the night it can be below freezing, with extremely low levels of rainfall, drought-tolerant plant species like cacti

Question 16

succession

Answer 16

a natural process that occurs over time as an ecosystem transitions from a barren or disturbed area, such as bare rock, to a more complex and mature community, such as a forest

Question 17

changes in succession

Answer 17

1) pioneer species start to colonise the area (barren rock)

2) pioneer species establish themselves and modify the abiotic conditions. (more conductive things for plants to grow)

3) progression of succession, shrubs and fast-growing tree species begin to dominate the landscape

4) stable and diverse ecosystem has been established

Question 18

factors that alter the progress of succession

Answer 18

soil conditions, climate, human interference, natural disasters

Question 19

process of photosynthesis

Answer 19

1) Plants absorb CO2 through the stomata

2) Plants absorb water through the soil in the roots

3) Absorption of light through chlorophyll

Question 20

word and symbol equation of photosynthesis

Answer 20

carbon dioxide + water + light energy → glucose + oxygen

6CO2 + 6H2O + light energy → C6H12O6 + 6O2

Question 21

word equation for aerobic respiration

Answer 21

glucose + oxygen → carbon dioxide + water + energy

Question 22

identify the different types of cells in a leaf (palisade mesophyll, spongy mesophyll, lower epidermis, upper epidermis and guard cells)

Answer 22

palisade mesophyll: contains high numbers of chloroplasts; responsible for most of the photosynthesis in the leaf

spongy mesophyll: arrangement allows for gas exchange, facilitating the movement of gases such (CO2 and O2)

lower epidermis: helps protect the leaf

upper epidermis: helps protect the leaf

guard cells: can change shape to open or close the stomata, regulating the movement of gases (CO2 and O2) and water vapour

Question 23

materials that glucose can be converted into after it has been made by photosynthesis

Answer 23

starch, cellulose, lipids

Question 24

how light intensity affects the rate of photosynthesis

Answer 24

as light intensity increases, the rate of photosynthesis increases as more energy is available for the process (can be too much light as CO2 and temp becomes limiting factors)

Question 25

how CO2 concentration affects the rate of photosynthesis

Answer 25

as CO2 levels increase, the rate of photosynthesis increases

Question 26

how temperature affects the rate of photosynthesis

Answer 26

different enzymes involved in the process have specific temperature ranges at which they work optimally. As temperature increases, so does the rate of photosynthesis, up to an optimal temperature

Question 27

why are mineral ions needed in order to make components such as proteins, DNA and chlorophyll (due to their chemical compositions)

Answer 27

proteins: are composed of amino acids, so mineral ions provide essential elements that are incorporated into amino acids

DNA: is composed of nucleotides, which consist of a sugar molecule (deoxyribose), a phosphate group, and a nitrogenous base. Mineral ions are necessary for the formation of DNA molecules

chlorophyll: has a complex structure with a porphyrin ring at the core. The porphyrin ring contains a central magnesium (Mg) ion, which enables chlorophyll to absorb light energy and initiate the process of photosynthesis. Without magnesium, chlorophyll cannot function effectively, leading to reduced photosynthetic activity

Question 28

life cycle of a plant

Answer 28

germination: under favourable conditions of moisture, temperature, and light, the seed absorbs water and swells (grows root)

growth and development: the germinating seed develops into a seedling, characterised by the emergence of leaves. the seedling undergoes further growth, developing a root system and establishing itself in the soil

flower formation: during the reproductive phase, the plant produces flowers

pollination: transfer of pollen grains from the anther (the male part of the flower) to the stigma (the female part of the flower). it’s through pollination that the male gametes are delivered to the female gametes for fertilization

fertilisation: a pollen grain lands on the stigma and forms a pollen tube that grows down through the style to reach the ovary (fusion of male and female cells)

fruit formation: ovary of the flower develops into a fruit

Question 29

process of germination and state the conditions necessary (water, oxygen, warmth)

Answer 29

germination is when a seed develops into a plant

water: softens the seed coat, initiates enzyme activity, and allows for the uptake of nutrients

oxygen: necessary for cellular respiration

warmth: stimulates enzymatic activity and speeds up metabolic processes

Question 30

define productivity

Answer 30

refers to the rate at which organisms within an ecosystem produce biomass or energy through photosynthesis or other metabolic processes

Question 31

flow of energy in a food chain

Answer 31

flow of energy in a food chain refers to the transfer of energy from one organism to another as they consume and are consumed by each other

(see book)

Question 32

why is energy lost between trophic levels and how does this limit its length

Answer 32

heat loss during metabolism: organisms use energy they obtain from food for their own processes like respiration, growth, and reproduction. energy is converted into heat and released into the environment. this heat loss is unavoidable and represents a loss of energy from the system

inefficiency in energy transfer: energy transfer between trophic levels isn’t 100% efficient. When an organism consumes another, only a fraction of the consumed energy is converted into biomass and made available for the next trophic level

Question 33

herbivore

Answer 33

an organism that mostly feeds on plants

Question 34

carnivore

Answer 34

an organism that mostly eats meat, or the flesh of animals

Question 35

producer

Answer 35

any kind of green plant

Question 36

primary consumer

Answer 36

make up the second trophic level. they’re also called herbivores. they eat primary producers—plants or algae—and nothing else

Question 37

secondary consumer

Answer 37

eat primary consumers. secondary consumers are mostly carnivores

Question 38

tertiary consumer

Answer 38

carnivores that feed largely on the primary consumers and secondary consumers. carnivores that feed on other carnivores are considered tertiary consumers

Question 39

sigmoid population growth curve + limits to the population at each stage (lag, exponential and stationary)

Answer 39

also known as the S-shaped curve, represents the growth pattern of a population over time

lag phase: pop is small and experiences slow growth. occurs when a population is introduced into a new environment or after a period of decline (adapting to it)

exponential phase: pop. experiences rapid growth. rate of reproduction exceeds the rate of mortality, resulting in an accelerating increase in population size (abundant resources and favourable environmental conditions)

stationary phase: population stabilises + reaches a constant size. limit to the pop. in the stationary phase is determined by the carrying capacity of the environment. the availability of resources becomes limited, leading to competition for resources, and increased predation

Question 40

carrying capacity

Answer 40

refers to the maximum number of individuals of a species that a particular environment can sustainably support over a given period