What is it called when part of a cell membrane closes around a molecule to allow the molecule to enter the cell?

Nucleic acid certain protein cell membranes certain carbohydrates

Kinases add - groups to other enzymes. this activities some enzyme while inhibiting other

How do water’s relative densities as a solid and a liquid differ from that of most other substances? water’s solid and liquid forms have different densities, while most other substances have solid and liquid forms with similar densities. water’s solid and liquid forms have similar densities, while most other substances have solid and liquid forms with different densities. water’s liquid form is less dense than its solid form, while the opposite is true of most other substances. water’s solid form is less dense than its liquid form, while the opposite is true of most other substances.