Answer: 4
Explanation:
It is composed of a cell, but does not have
tissues.
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:
Steps to cellular respiration:
1) In the first step of respiration, glycolysis occurs in which glucose molecule is converted into pyruvate molecule.
2) Krebs cycle is also called citric acidity cycle. In this cycle, hydrogen and electron are produced from the oxidation of pyruvate molecule and provides to electron transport chain.
3) Electrons carried by NADH + H and FADH2 are converted into oxygen through a series of electron carriers, and production of ATP occurs.
Answer:
A. Hydrogen bonds
Explanation:
A. Hydrogen bonds causes water molecules to stick together in liquid water.
