Answer:
A: Eating a sandwich
Explanation:
During labs eating is a big no. Some food can catch on fire, or be contaminated or breed germs that can affect the experiment. Wearing googles is a good idea and tying back hair is a must when using fire. The work area should always be clean so A is the answer
NaOH is not a compound because it contains three instead of two.
Answer:
The growth factor receptors have a kinase domain while the Cytokines receptors do not contain a kinase domain as part of their structure.
Explanation:
The two are signaling molecules that control cell activities in some manners, such paracrine, endocrine and autocrine manners.
The receptor kinase domain can be specific for substrate sites in which phosphorylation occurs.
Answer:
Oxygen levels stay above 15 percent starting 200 million years ago
Explanation:
Atmospheric oxygen levels are related to the evolution on Earth and changes in geochemical cycles that involve climate variations.
The presence of O
2 and evolution of oxygen gave new opportunities to the life on Earth. Oxygen levels in atmosphere have fluctuated between 15% and 35% of atmospheric volume, since the start of the Cambrian period.
So, form the starting 200 million years ago, oxygen level stay above 15 percent and the correct option is "B".
