Answer:
The answers are:
1. initial composition of microbial community (controlled variable)
2. age of the mice (controlled variable)
3. change in body fat (dependent variable)
4. diet (independent variable)
5. weight gain (dependent variable)
6. final composition of the microbial community (controlled variable)
Explanation:
Before I go ahead to explain each of the choices of classification, let us define each of the different types of variable.
1. Independent variable: this is a variable that is under the control of the experimenter. It is made up of the factors that are being tested. In our example, the independent variables is; diet. The aim of the experiment is to study the effect of the type of diet on the mice. The diet can also be varied and assigned at will by the experiment.
2. Dependent variable: a dependent variable is one whose outcome is reliant on the effect of the changes in the independent variable. It is the factor to be measured. In our example, the factors that obey these definitions are; change in body fat and weight gain. these two factors depend on the types of diet taken by the mice, hence they are the factors to be measured.
3. Controlled variable: these are variables that are kept constant throughout the experiment to rule out biases, because they produce the same effect on the dependent variable as the independent variable and must be keep constant or uniform in the test groups. in our example, the factors that are controlled include; initial and final compositions of the microbial communities and the age of the mice, because the microbial composition if not uniform among the groups can cause biases in how the diets are processed, and the age of the mice also must be uniform to avoid age-related differences in the processing of the diets
They would die or have to have food digested for them.
Answer:
1) Wax belong to lipids.
2) <u>Animals</u>: Water and cold isolation and protection from pathogenic microorganisms.
<u>Plants</u>: It controls evaporation and maintains hydration.
Explanation:
1) Wax belong to the biomolecules of lipids.
2) In animals, such as birds, the uropygial gland secrets sebum or wax, spreading it throughout the animal's feathers to prevent water from penetrating as it serves as an isolating compound for animals that live in cold areas. It also provides protection from bacteria and fungi. In coloquial terms, it would be like a water-proof coat that protects them from water and extreme climate.
In plants, the secretion of wax through the cuticle has been developed as an adaptation to control evaporation and maintain hydration.
A culture medium consisting of agar, human blood, and beef heart is a
B) Complex medium
The correct answer is (B) Photosynthesis and diffusion from the air
Dissolved oxygen enters the water from photosynthesis and through air. The The aeration of water can be caused by wind. From the air oxygen diffuse into the water and gets mixed in the it through circulation. The oxygen is also produced as a waste product of photosynthesis from blue-green algae, phytoplankton, etc which is added in water.
