When cells communicate by the signaling process, one cell produces a signaling molecule that must be received by the signal receptor on or in the responding cell. Signaling molecules are often called ligands, a general term for molecules that bind specifically to other molecules (such as receptors).
Answer:
Circulatory system remove waste from the cell and provide clean blood to the cell.
Explanation:
During cellular respiration, lungs inhale oxygen which stored in the alveoli. The red blood cells contains hemoglobin that carries deoxygenated blood containing carbondioxide from the cell in the veins to the heart and unload this carbondioxide gas in the alveoli of the lungs and load oxygenated blood having oxygen from the alveoli through capillaries in order to provide oxygen to the cells that is necessary for the survival of humans. Platelets are the type of cells that helps in blood clotting whereas white blood cells provides immunity against pathogens.
<span>Living things are made of cells.Living things obtain and use energy.Living things grow and develop.Living things reproduce.Living things respond to their environment.<span>Living things adapt to their environment.</span></span>
Answer:
Index Fossils can be used to identify a specific time period.
Explanation:
Answer:
10 H atoms combine with 5 oxygen to form 5 water molecules.
Explanation:
those substances which having low boiling point or low melting point such as water they form covalent bond.
Covalent bonds form between non-metal atoms. Each bond consists of a shared pair of electrons, and is very strong. Simple molecular substances and giant covalent structures have different properties.