Answer:
1. Signaling molecule
2. Signaling receptors
Explanation:
Hormones, growth factors, neurotransmitters, etc. serve the function of signaling molecules for cells. These molecules are released by one cell and bind to the receptors present on/in the target cells to elicit the desired response. Thereby, the signaling molecules serve in cell-cell communication.
For example, insulin hormone synthesized and released from beta cells of pancreas binds to its cell surface receptors present on the surfaces of liver cells and muscle cells to stimulate the uptake of the glucose from the blood.
Likewise, neurotransmitters released from the presynaptic neuron bind to receptors present on the membrane of postsynaptic neuron and serve to carry the nerve impulse to the postsynaptic neuron.
Answer:
Bacteria are eukaryotes
They have a single DNA,circular chromosome
Explanation:
It's their basic characteristics that they share .
If another predator, that is more efficient hunter, enters the territory of the puffins, the puffins will find themselves in a very tough situation. They will either have to adapt very quickly, or die out.
The evolutionary pressure will be there fro the puffins to push them in a direction to adapt and be netter hunters, thus fight for their existence. That would mean that the puffin's beak, but also their speed and efficiency will have to improve in order to compete or even out-compete the new predator.
If the puffins do not manage to adapt relatively quickly, and a food shortage occurs, than they will die out, as they will lose the fight for food constantly.
Answer: B. 0.77
Explanation:
We should note that from the Hardy-Weinberg law, the formula used is:
p²+ 2pq+ q² = 1
From the information given,
p = purple allele
q = red allele
q² = 59/100 = 0.59
Then, the frequency of the red allele that is recessive will be:
q² = 0.59
q= √0.59
q = 0.768.
q = 0.77
Therefore, the correct option is B.
