I think salt is it
........................
Answer:
Explanation:
Proteins are important because they give you ability to fix broken bone or to grow.
Answer:
This question appears incomplete but The correct option is the last option
Explanation:
Cell membranes are made up of a lipid/phospholipid bilayer in which each layer consists of an hydrophilic head (water loving) and a hydrophobic tail (water fearing). The hydrophobic tail of each layer is oriented inward and the hydrophilic heads are oriented outward so the cell can interact with water molecules inside (the cytoplasm) and outside the cell environment. This orientation forms a critical part of the function of the cell membrane that makes it a selectively permeable barrier that regulates what goes in and out of the cell.
Answer:
B (active transport using ATP)
Explanation:
Movement of substances normally occur in the direction of concentration gradient/difference i.e. the difference in concentration of a substance across a membrane. Letting molecules diffuse or pass down their concentration gradient does not require energy but pumping those molecules against gradient requires energy in form of Adenosine triphosphate (ATP). This process is called Active transport.
In order to perform certain cellular processes, cells need to move substances from their surroundings into the cell across their cell membrane. Moving this substances against the concentration gradient between the cell membrane and its extracellular fluid requires energy (ATP).
An example is the sodium-pottasium pump employed by animal cells in which they expend energy to move K+ molecules into the cell and Na+ molecules outside the cell against the concentration gradient of their cell membrane and extracellular solution.