The positive movements of a plant shoot in response to light or movement of shoot towards the source of light is called as Phototropism. If the part of a plant moves away from light, this movement is called as Negative Phototropism.
Growth and movements in plants occur due to internal and external factors. Plant hormones are internal factors while light, touch, gravity and other stimuli are external factors that affect plant growth and movements.
ASSESSMENT: NCERT QUESTIONS WITH ANSWERS
The reflex action is an involuntary action which goes on automatically. We don’t have any control on this type of action. Walking, on the other hand is a voluntary action which can be controlled and modified by us.
Cattle dung has been used in India to sweep cutcha houses and to make cakes for burning in kitchens. One of the best uses of dung is for making compost etc. manure. Indians, especially Hindus use cow dung for making compost, dung cakes and for religious purposes.
Bamboo can be said as the Green Gold to Indian Farmers as it provides vast varieties of benefits to them.
When both the ovaries are fully mature, they alternatively produce ova at the interval of 28 days. Release of ovum into the uterus through the fallopian tube is called as ovulation.
Anthills show the quality of soil.
A substance, factor, change, living being or a system that quantifies and simplifies phenomena and helps in understanding complex realities, is called as indicator.
It tells us something about changes in a system. There are many types of indicators some of which are- Financial Indicators, Poverty Indicators, Health Indicators, Environmental Indicators, and Indicators of Sustainable Development.
Two organisms- male and female are essential for sexual reproduction. Now let us study some basic methods of reproduction in single organisms.
Forests and wildlife are integral part of environment. Forests control climate, soil erosion and wildlife. They cause rains.
Some environmentalists define land pollution as – build up of toxic chemical compounds, salts, pathogens or radioactive materials in soil that can affect plant and animal life adversely, is called as soil pollution.
Ladybird is one uncommon compound word made by the union of two simple common words – Lady and Bird. But, the two simple words when joined together can produce strange effect.
