Humans add substances to the water
Answer:
Africa or any middle Asia
Explanation:
Because the weather is dependent on the sun... In the morning when there is sun, it gets much hotter and warmer...
In the night when the sun is gone the temp gets little lower and make it colder
Answer:
10,000 years
Explanation:
Fossils are defined as the remains or traces of organisms that died more than 10,000 years ago, therefore, by definition the minimum time it takes to make a fossil is 10,000 years. But, that is just an arbitrary line in the sand – it means very little in terms of the fossilisation process.
Answer:
Explanation:
Osteoporosis is a disease of bones. It occurs when bones loose density and structure of bone becomes porous. This condition leads to weaking of bones and the bones may break.
Causes : The low calcium diet in food, estrogen deficiency in women, Vitamin D deficiency and high levels of thyroid hormone secretion, too much alcohol consumption, smoking and medical condition of cystic fibrosis also result in bone weakening are responsible causes of osteoporosis.
Prevention : It can be prevented by medication, weight bearing physical exercises which can prevent loss of bones and provide strength, healthy diet with calcium and Vitamin D supplements.
Answer: False
Light receptor cells are not present in the skin but they are present in the retina of the eyes.The retina is the black part of the eye that exhibit light sensitive receptor cells called as rods and cones. Rods are sensitive to the intensity of light and cones are sensitive to color of light.