Answer:
Part 1. The amount of calcium is independent variable.
Explanation:
An independent variable is a variable in an experiment which is changed to see its effects on dependent variable.
In this experiment, to know about the causes of osteoporosis, the Ca level in blood or calcium intake in changed.
So the concentration of calcium will be independent variable.
Part 2.
The risk of bone fractures is could be changed with calcium.
Explanation:
In this experiment osteoporosis or risk of bone fracture is dependent variable.
Dependent variable are results of experiment which can be changed by independent variable.
As in experiment, Calcium concentration is independent variable.
So the risk of osteoporosis depends can change with calcium.
Answer: True, both of the given statements are true.
Explanation:
1. Nearly all the environment contains microorganism whether it is soil, air, water or any other surface. They have the ability of live in the extreme conditions.
There are different forms of bacteria found at different places. Some of them are thermophiles that at found in extremely hot conditions such as thermal vents.
The organism like Psychrophiles are the microorganisms that have the ability to survive at lower temperatures. Example: bacteria found in polar regions.
2. A culture can be defined as a pure culture if it has an unadulterated species of bacteria. It has no contamination and if a small inoculum from the pure sample is streaked on a plate then a pure culture of the sample is obtained.
This should be done in an aseptic condition so that the bacterial species should be free from contamination.
28. bacteria and fungi.
29. answer 3
30. answer 2