Correct Answer: C. courtship

Explanation

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Correct Answer: A) guard cells

Explanation

Stomata are tiny openings on the leaves of plants that allow for gas exchange, which is important for photosynthesis. The question is asking about the mechanisms that control the opening and closing of stomata. The options given are guard cells, stoma, lenticels, and air spaces. The correct answer is option A: guard cells. Guard cells are specialized cells that surround the stomata and control their opening and closing. When the plant needs to conserve water, the guard cells close the stomata to reduce water loss through transpiration. When the plant needs to take in carbon dioxide for photosynthesis, the guard cells open the stomata to allow for gas exchange. Stoma, on the other hand, are the actual openings themselves, while lenticels are small pores on woody stems that allow for gas exchange. Air spaces are also important for gas exchange, but they are not directly involved in the opening and closing of stomata. Understanding the function of guard cells is important for understanding how plants regulate their water use and perform photosynthesis. To learn more about this, please read the relevant sections of the recommended textbooks.

Correct Answer: D. Stickyjuice

Explanation

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Correct Answer: C. Transportation

Explanation

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Correct Answer: D. calcium, magnesium and potassium

Explanation

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Correct Answer: C. Tonoplast

Explanation

The membrane around the vacuole is known as Tonoplast. The tonoplast is the cytoplasmic membrane surrounding a vacuole, separating the vacuolar contents from the cell's cytoplasm. It is also known as Vacuolar membrane.

Correct Answer: A. possess valves at internals throughout their length

Explanation

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Correct Answer: C) Oxygen

Explanation

Air pollution is the presence of harmful substances in the air that we breathe. The question is asking which of the options listed is not a major air pollutant. The options listed are carbon monoxide, ozone, oxygen, sulphur dioxide, and hydrogen. Carbon monoxide is a poisonous gas produced by incomplete combustion of fuels. It reduces the amount of oxygen in the bloodstream and can cause headaches, dizziness, confusion, and even death. Ozone is a gas that is formed from a chemical reaction between nitrogen oxides and volatile organic compounds in the presence of sunlight. It is a major component of photochemical smog and can cause respiratory problems. Sulphur dioxide is produced by burning fossil fuels and is a major contributor to acid rain. It can cause respiratory problems and can also harm plants and animals. Hydrogen is not a major air pollutant and is actually an important component of water. The correct answer to the question is option C, oxygen. Oxygen is not considered a major air pollutant as it is necessary for the survival of most living organisms. It makes up about 21% of the Earth's atmosphere and is required for respiration. However, excessive amounts of oxygen can also be harmful and can lead to oxidative stress and damage to cells. In summary, the correct answer to the question is option C, oxygen, as it is not considered a major air pollutant. Carbon monoxide, ozone, and sulphur dioxide are all major air pollutants that can cause harm to living organisms and the environment. Hydrogen is not a major air pollutant and is actually an important component of water.

Correct Answer: B. II

Explanation

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Explanation

(a) Kidney diseases

(c) (i) Estuarine habitat; is the place point where a river enters to ocean/sea, into which the tides flow; fresh water mix with salt water; to form brackish water.

(ii) food chain typical of an estuarine; phytoplanktons - branacles => fish => bridORDetritus => worm => molluse => birdORDetritus => shrimp => fish => bird

(d)(i) Pests that can attack plant crops :

Stem borer

army worms

weevils

black tea-thrips

aphids

root mealybugs

variegated grasshopper

beetle; rodents

squirrel

locust

birds

mites

cotton stainer

any correctly named examples.

NOTE : Spelling must be correct to score.

(ii) Ways of controlling plant diseases

• Chemical control/ use of fungicides/ nematicides/ bactericides/ pesticides
• Biological control/ use of predators and parasites of insects/ pests to keep them in check
• Breeding resistant varieties of crop
• Planting genetically modified crops that can resist viruses/ bacteria transmitted by pests
• Destruction of infested crops by burying/ deep burial/pruning of affected parts
• Destruction of alternate host
• Adopt good management/ crop rotation.

(e). Functions of a public health authority

• ensures cleanliness of public places/markets/schools/playgrounds
• concerned with the proper disposal of refuse
• provides maternity clinics/health centres/nursing homes/family planning
• provides child welfare services
• provides medical inspection of schools
• registers birth/death
• prevents controls infectious diseases/ administers vaccination/ immunization/ inoculation
• informs World Health Organization of the outbreak of infectious diseases
• ensures adequate provision of clean water to the public
• provides ambulance services
• provides quarantine services for plants/ animals/ humans
• gives health certificate to travelers
• provides public health education/awareness of diseases
• inspects and certifies health of animals and cleanliness of slaughter house/ abattoir.

(f). Ways of maintaining food hygiene : -

1. proper harvesting/ storage methods must be ensured to prevent damage to food items
2. food items must be properly washed/ cleaned to prevent contamination
3. food items must be properly cooked at appropriate temperatures
4. kitchen/cooking areas must be kept clean always/free from germs
5. perishable food items must be properly preserved/ refrigerated
6. proper personal hygiene must be observed by those handling food
7. cooking utensils must be properly washed/ cleaned before and after use
8. cooked/prepared food must be covered at all time
9. proper disposal of unused/leftover food.