Discussion Forum Latest Questions

Ayushree

(i) Alveoli are tiny air sacs in lungs where exchange of gases occurs. Oxygen diffuses into blood, and carbon dioxide diffuses out.(ii) Stomata are small pores on leaves that allow exchange of gases and water vapour. CBSE Sample Paper Class ...

Ayushree

Plants excrete wastes in several ways. Excess water is lost through transpiration. Oxygen from photosynthesis diffuses out through stomata. Some wastes like gums, resins, and latex are stored in old xylem or special cells. Leaves and bark shedding also remove ...

Ayushree

The correct answer is [C] A is true but R is false.The maximum concentration of chemicals and pesticides occurs at the highest trophic level, not the first. These chemicals are non-biodegradable, so they accumulate through the food chain, causing ...