Most invertebrates leave their young to fend for themselves while vertebrates help their young till they are ready
Answer:
most likely silt.
Explanation:
its not humus cause humus is sticky. its not sand cause when sand is wet its very gritty and hard. its not gravel because gravel is gritty. hope this helped
Answer:
where's the options for this question?
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.