Question

what is the function of mitochondria? please draw the structure, labeling the inner, outer membranes, matrix, and intermembrane space.

what are the cytoskeletons and what are their functions?

. what are the tight, gap and anchoring junctions?

. define amphipathic

. what are the functions of membrane proteins

. what will happen to a cell if it is placed into a hypotonic solution? hypertonic solution? isotonic solution?

. if a molecule moves across the membrane using a protein channel, it is called ?

. if a molecule moves across the membrane using a protein channel and 3 ATP, it is called

Answer 1

Mitochondria: It is a part of eukaryotic cells. The main function is to perform cellular respiration by producing ATP and to regulate cellular metabolism.

INTERMEMBRANE SPACE INNER MEMBRANE MATRIX OUTER MEMBRANE

Cytoskeleton: It is a network of tubules and filaments which is spread through cytoplasm in entire cell except nucleus. It directs the following functions:

1. Maintainence of the cell shape.

2. Gives support to the cell.

3. Provides cell migration.

4. Assists in the communication signals.

Tight junctions: It is also known as occluding junctions. It is a multiprotein junction which serves to prevent leakage of transported solutes and water.

Gap junction: Also known as Communicating junctions, which allows chemical communication between cellular cytoplasm through the process of diffusion.

Anchoring junction: Hold cells together and also provides tissues with structural cohesion.​​

Amphipathic​​​​​: It is a molecule that has both hydrophilic or polar end and a hydrophobic or nonpolar endpolar end.

The functions of membrane proteins

• Activity of enzyme
• Signal Transduction.
• Intercellular Joining.
• Cell-cell recognition.
• Transport of chemicals.
• Attachment to the cytoskelton & extracellular matrix.

If a cell is placed in a hypertonic solution then the cell will shrink as water will leave the cell. In an isotonic environment, the relative concentrations of solute and water are equal on both sides of the membrane. Hence, there would be no movement. In the hypotonic environment flow of water will be into the cell.

If a molecule moves across the membrane using a protein channel then it is called Passive transport.

If a molecule moves across the membrane using a protein channel and 3 ATP then it is called active transport.