Question

Describe the fluid mosaic model (cell membrane):

Cilia

Flagella

Microvilli

Gap junction

Tight junction

Desmosome (adhering junction)

Define

Transport

            Diffusion

            Osmosis

            Active transport

            Facilitated diffusion

            Exocytosis

            Endocytosis

Phagocytosis

                        Pinocytosis

                        Receptor-mediated endocytosis

           

            Hypertonic

            Hypotonic

            Isotonic

A cell (46% salt) is placed in a solution of 21% salt. The cell is in a(n) ______________ solution, and it will ____________________ weight.

A cell (12% sugar) is placed in a solution of 20% sugar. The cell is in a(n) ______________ solution, and it will ____________________ weight.

Answer 1

Fluid mosaic model consist of Lipid Bilayer with interspersed proteins inbetween that acts as channel for transport of ions.

Cilia - is a projection from the cells made up of microtube and present widespread over cell and help in motility.

Flagella - similar to cilia but larger and present single or in group as Unipolar or bipolar flagella. They also help in motility of cells.

Microvilli - micovilli are multiple small projection from cell membrane to increase the surface are of cell. It may increase the absorption or secretary capacity of cell.

Gap junctions - provide cytoplasmic channels from one cell to other cell.

Tight junctions - they prevent leakage of water between two adjacent cells.

Desmosomes - provide strong adherence at intercellular junction.

Transport - is movement of solute from one medium to another.

Diffusion - Passive transport of solute along concentration gradient from higher concentration to lower concentration.

Osmosis - movement of solvent from less concentrate side to high conncetrated side seperated by a semipermiable memberane.

Active transport - transport of solute against concentration gradient by utilising ATP.

Facilitated diffusion - it is passive transport with help of a channel.

Exocytosis - transport of substance out of cell by packaging in a vesiscle.

Endocytosis - sustance is taken inside cell by invagination of cell membrane.

Phagocytosis - it is endocytosis by cell and then killing the pathogen inside the cell.

Pinocytosis - it is also called cell drinking, invagination of liquid by cell membrane.

Receptors mediated endocytosis - endocytosis with the help of receptors. E.g. LDL receptors

Hypertonic - high Osmolarity

Hypotonic - low Osmolarity.

Isotonic - equal Osmolarity

A cell (46% salt) is placed in a solution of 21% salt. The cell is in a(n) _hypotonic_ solution, and it will __Gain____ weight.

A cell (12% sugar) is placed in a solution of 20% sugar. The cell is in a(n) ___hypertonic_____ solution, and it will ______loose____ weight