B. One
because an independent variable is something you change. So in a scientific experiment you only change one thing. If you happen to change more than one thing then the test becomes unfair therefore you should repeat and make sure that only one thing is changed this time.
Answer:
A. Cellular respiration
C. Photosynthesis
Explanation:
There are two main processes occurs in the carbon cycle i.e. cellular respiration and photosynthesis. Plants absorb carbondioxide gas from the atmosphere through small openings called stomata. The carbondioxide enters the leaves and combine with water produces glucose and oxygen. Glucose is stored in different parts of plant whereas some oxygen is used by the plant and the remaining oxygen is releases in the atmosphere while on the other hand, in cellular respiration, glucose is broken down to produce energy in the form of ATP, carbondioxide gas and water.
Answer:
<u>stonewort, and many green algae such as the Spirogyra.</u>
Explanation:
- As it was believed that the land algae were believed to be evolved from the stonewort plant and the blue-green algae like the cyanobacteria and the spirogyra that colonized the lands some 500 mn years ago was a freshwater alga.
- After which the first land plants occur about 470 million years ago, and they were in the form s of moss and liverworts of the vascular in origin.
I think the answer is Phenylketonuria.