The correct answer is C because it speaks of organisms
The classification system for organisms has changed from seven levels to eight. This happened because scientific consensus changed as scientists learned more about organisms.
Answer:
Explanation:
Most limestones actually start as calcium carbonate mud or shells precipitated by organisms in reefs or shallow shelf regions - the biosphere. Over time, the limestone is broken down into its chemical parts and may come back to the surface as volcanic CO2 (in the atmosphere).
1. C) The soil will have no nutrients to grow the corn.
2. C) Crops may cause an increase of allergic reactions in humans
3. B) Decomposers
Answer:
The answer is A.
Explanation:
B) Nucleotides and amino acids can act as extracellular signal molecules:
ATP is made of adenosine (a type of nucleotide) and used in cell signalling called "purigenic signalling" and amino acids are also used as signal molecules.
C) Some signal molecules are transmembrane proteins:
Transmembrane acts as receptors for smaller signal molecules so this can also be accepted as true.
D) Some signal molecules can bind directly to intracellular proteins that bind DNA and regulate gene transcription:
That is also true, some of the hormones can cross lipid membrane of the cells and bind directly to the intracellular (inside-of-a-cell) proteins.
Lastly; dissolved gasses such as nitric oxide can activate proteins such as guanylyl cyclase so this choice is <u>false</u>.
