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Question 1

Membrane transport

Answer 1

A biological membrane is semipermeable, meaning it is permeable to some molecules, most notably water, while being very impermeable to most solutes (various biochemicals and salts) found in the bathing solution. The membrane determines what solutes enter and leave a cell. Transmembrane transport is controlled by complex interactions between membrane lipids, proteins, and carbohydrates.

Question 2

Transport types

Answer 2

Vesicle mediated:
Endocytosis = The process by which cells take in substances from outside of the cell by engulfing them in a vesicle. These can include things like nutrients to support the cell or pathogens that immune cells engulf and destroy. Example; Phagocytosis, pinocytosis and receptor-mediated endocytosis.

Exocytosis = The process by which cells move materials from within the cell into the extracellular fluid. Exocytosis occurs when a vesicle fuses with the plasma membrane, allowing its contents to be released outside the cell.

Question 3

Trough the membrane:

Answer 3

Without carrier / with carrier = Transport through lipid bilayer, statistic pores and protein channels depending on the driving forces (gradients) whether it is diffusion, osmosis and filtration.
According to mechanism of activation (gating):
Voltage - gated
Ligand - gated
Stress - activated

According to direction and number of transport solutes it can either be:
Uniport - import and export
Co-transport -s import and antiport

According to the charge balance:
electrogenic
electroneutral

Question 4

Pasive or active

Answer 4

Transport can either be passive or active. Passive means that it does not require energy for the transport and active means that it requires energy for the transport through membrane.