Biology Flashcards

Question

Define pollution.

Answer 1

Pollution is the introduction of harmful substances into the environment, endangering both ecosystems and human health.

Answer 2

Agricultural practices Industrialization Improper garbage disposal

Answer 3

Chemical fertilizers: Cause eutrophication, harming aquatic life and harm earthworms, vital for soil fertility and structure. Insecticides: Harm all insects, including beneficial pollinators, and pose risks to human health. They persist in the environment, poisoning aquatic life when washed into rivers and seas, and concentrating up the food chain, potentially harming top consumers.

Answer 4

Due to industrialization, what are two air pollutant sources? What pollutants do they generate, what are the pollutants’ negative impacts, and what are some solutions to conserve and restore the environment? (1) Construction work/cement factories: Produce dust. Dust settles on buildings and plants, reducing photosynthesis, resulting in less food for animals. Dust also enters rivers, leading to siltation of mangrove swamps and the sea, causing destruction of aquatic life. Dust also causes respiratory diseases such as asthma. Solutions include frequent washing of plant leaves and wearing dust masks. (2) Burning fuels in vehicles and industry: Produces gaseous smoke and smoke particles. Smoke particles affect human health, causing bronchitis. The smoke contains greenhouse gases such as carbon monoxide, which enter the atmosphere, contributing to global warming. Gases can dissolve in rainwater to produce sulfuric, nitric, or carbonic acid, producing acid rain, which kills plants and hence animals. Solutions include wearing dust masks, utilizing emission control devices and instead of allowing greenhouse gases to enter the air, using them to make fertilizers such as sulfates and nitrates. Cleaner fuel sources such as gasohol or burning garbage for energy to generate electricity can be utilized. Furthermore, altering processes to produce fewer pollutants can help. In addition, alternative forms of energy such as wind, solar, or hydroelectric power can be used.

Answer 5

Aluminium plants: Produce chemical waste and caustic sludge. These pollutants are released into ponds and rivers, killing aquatic life such as fish. Solutions include treating effluence, disposing of waste in proper areas, and passing laws for industries to change chemical waste into less harmful substances. Desalination plants and electric power stations: Produce "industrial heat." This hot water enters aquatic habitats. High water temperatures can lead to coral bleaching, destroying coral reefs. Less oxygen dissolves in hot water; therefore, less oxygen is available for the respiration of animals. The solution to this is cooling water and directing it to ponds. Drilling in sea and on land: Produces oil spills. These kill plants and animals. Solutions include using detergent, however, this is also a pollutant, or the use of microbial action.

Answer 6

Burning garbage: This causes toxic gases to enter the atmosphere, increasing the amount of greenhouse gases in the atmosphere. Solutions include avoiding burning garbage, burning biodegradable garbage in incinerators, and using the energy produced to generate electricity. Dumping garbage on empty lots or in rivers: This is unsightly and foul-smelling. It also creates a breeding ground for pests such as rats and roaches, which can be vectors of disease. This causes pollution of soil and water. Furthermore, non-biodegradable materials such as plastics enter aquatic habitats, killing aquatic life. Solutions include educating the public to reduce, reuse, and recycle. Biodegradable waste should be used to make compost heaps, and food processing waste can be used to make organic fertilizers. Landfill sites: If garbage is not treated and buried quickly, this can be a breeding ground for pests, which can act as vectors of disease. It also creates a bad odor, which can have a negative health impact on the residents living near the landfill. Solutions include using methane gas produced from landfills to generate electricity.

Answer 7

1. Destruction of Tourist Attractions (coral reefs, mangroves, beaches) 2. Dust and Smoke in the Air 3. Unsightly, foul-smelling garbage present

Answer 8

1. Loss of income for economy and aesthetics 2. Destruction of habitats and aquatic life 3. Less seafood for humans

Answer 9

Energy conservation: Educate the public through schools and mass media about the need to conserve energy by using less electricity or considering alternative sources of energy. Use of alternative sources of energy: For example, solar, wind, burning garbage, and hydroelectric power. Vehicles can use electricity or gasohol (a mixture of ethanol and gasoline). Biogas: Can be used for cooking as an alternative to fossil fuels. Utilising methane produced from fossil fuel use: Instead of methane entering the atmosphere, it can be used as an energy source to generate electricity.

Answer 10

Less minerals should be used due to the limited supply. Governments can impose a mining tax to disincentivize the exploitation of minerals. Metals can be recycled and reused.

Answer 11

Trees are removed for the following reasons: paper, timber, housing, agriculture, roads, industry, and medicine. The effects of the removal of trees are: Reduces the amount of food available for animals since plants photosynthesize and manufacture food. There is an increase in the level of carbon dioxide in the air as plants use carbon dioxide during photosynthesis. Habitats are destroyed which can lead to the depletion or extinction of species. Erosion of topsoil.

Answer 12

Erosion of topsoil leads to loss of soil fertility, silting of the waters, floods, landslides, and loss of livestock and crops. This can lead to the loss of income for farmers, resulting in high economic costs. Measures to conserve forests and soil include: Reforestation programs. Designating certain areas as nature reserves to protect trees and wildlife. Implementation of soil conservation plans.

Answer 13

Overfishing: Humans fish for seafood, leading to the depletion or extinction of certain species. Overfertilization: Excessive fertilizer use can pollute the sea and cause eutrophication, resulting in the overgrowth of marine algae. Destruction of coral reefs: Eutrophication reduces light to coralline green algae zooxanthellae, leading to the death of coral polyps. Oil spills: Oil spills from offshore drilling and tankers can kill marine life.

Answer 14

[Refer to textbook page 30.]

Answer 15

RECALL: Never Mind I Play Cricket Properly Sancho [Refer to textbook page 77.]

Answer 16

Reduces the buildup of waste. Recycles nutrients. Aids in the flow of energy in the ecosystem.

Answer 17

Carbon dioxide absorbs radiant energy. Carbon dioxide radiates heat to Earth.

Answer 18

Decomposers require no light for their nutrition, depend on other organisms for food to break down organic molecules into simpler molecules. Plants, on the other hand, require light for their nutrition, are autotrophic meaning they make their own food, and use simple molecules to make organic molecules.

Answer 19

Plant more trees. Reduce combustion.

Answer 20

The concentration of water vapour in the air is less than the concentration of water vapour in the intercellular airspace, so it diffuses out of the airspace. Water evaporates from cell surfaces into the intracellular airspace. Water is drawn from mesophyll cells via osmosis. Water from xylem vessels replaces lost water in mesophyll cells via osmosis. This creates a transpiration pull. Water moves up xylem as a continuous column due to capillarity, root pressure, and transpiration.

Answer 21

Light intensity: During daytime when photosynthesis is taking place, stomata are open to allow carbon dioxide to enter. As light intensity increases, the rate of transpiration increases because the rate of diffusion of water vapour through the pores increases. When the light intensity decreases, the transpiration rate decreases because the pores begin to close. Temperature: There is faster evaporation of water at higher temperatures leading to a higher transpiration rate. At lower temperatures, the transpiration rate will decrease due to the slower evaporation of water. Humidity: High humidity means there is a greater amount of water vapour in the air and it cannot hold much more. Therefore, the transpiration rate will be low in times of high humidity. In low humidity (dry air), the transpiration rate increases. Air movement: Windy conditions will increase the transpiration rate because the water vapour will be removed quickly from the stoma. In still air, the transpiration rate will decrease because the air space is saturated with water vapour. Water availability: Stomata close when the guard cells become flaccid in times of water shortage, and the transpiration rate will slow down.

Answer 22

(i) Without any weight on the beam balance, move all of the counter masses to the zero marks. Turn the zero adjustment knob until the pointer aligns with the zero mark. Place the plant on the beam balance and record the initial mass. Place the plant by the window. Measure and record the mass of the plant after an hour has elapsed. Repeat steps 4 and 5 for a total time of 12 hours. Plot a graph of mass of the potted plant versus the time of day. (ii) Use a fresh and healthy plant OR Ensure that the polythene bag is properly sealed.

Answer 23

To make enzymes. To make hormones.

Answer 24

[Refer to notes.]

Answer 25

[See notes.]