Answer:
I am pretty sure that the answer is A.
Explanation:
Protein kinases regulate the cell cycle by giving the "go-ahead" or "stop" signal at checkpoints in the cycle. A mutation/disruption in the protein kinases can result in it not doing its job properly. As a result, it can give the 'go-ahead' signal to all cells (mutated or not) to continue through the cell cycle. A distrupted kinase will infleunce the enviornment for a cancer cell as the cancer cell can continue to divide continuously.
I do not think the answer is D because G-couped receptirs are not involed in the regulation of the cell cycle. Additionally, I do not think the answer is C since the production of cAMP (a secondary messgenger amplifies transduction signals; this doesn't have anything to do with cancer?) Finally, between A and B I know that a direct result of cancer is due to a distruption in either protien kinases or growth factors (not in the answer choices). Since one of the factors that leads to cancer is present in answer choice A, I think that is the one. However, this is just my reasoning, I am not 100% sure!
Answer:
The cell membrane is selectively permeable and able to regulate what enters and exits the cell, thus facilitating the transport of materials needed for survival. ...
Explanation:
Because the membrane acts as a barrier for certain molecules and ions, they can occur in different concentrations on the two sides of the membrane.
Answer:
Los gases que tienen huellas de carbono son dióxido de carbono, monóxido de carbono y gases de metano, etc.
Explicación:
Los gases contaminados que contienen huellas de carbono son dióxido de carbono, monóxido de carbono y metano, etc. Estos gases tienen un efecto negativo sobre el medio ambiente porque son responsables del calentamiento global de la atmósfera y disminuyen la calidad del aire que produce muchas enfermedades nocivas. Las principales causas de la emisión de gases contaminados son las actividades humanas como la quema de combustibles fósiles y el humo que producen las industrias, etc.
C. Changes to biodiversity can positively and negatively affect an ecosystem.
Explanation:
The best-known neurotransmitters responsible for such fast, but short-lived excitatory action are acetylcholine, norepinephrine, and epinephrine while GABA is the major inhibitory neurotransmitter. Neurons are the basic building blocks of the nervous system.