Exo/Endo cytosis & Transport (ORAL SCIENCE)

Question 1

What is Endocytosis

Answer 1

Endocytosis (Taking Substances into the Cell)

Question 2

What is Exocytosis

Answer 2

Exocytosis (Releasing Substances from the Cell)

Question 3

Explain the steps of Exocytosis

Answer 3

Exocytosis (Releasing Substances from the Cell)
1. Vesicle Formation – Inside the cell, a vesicle (small sac) containing substances forms.
2. Transport to Membrane – The vesicle moves toward the cell membrane.
3. Fusion with Membrane – The vesicle merges with the cell membrane.
4.Release of Contents – The substances inside the vesicle are released outside the cell.

Question 4

Explain the steps of Endocytosis

Answer 4

Endocytosis (Taking Substances into the Cell)
1. Detection of Substance – The cell detects a substance outside.
2. Membrane Engulfing – The cell membrane wraps around the substance.
3. Vesicle Formation – The membrane pinches off, forming a vesicle inside the cell.
4.Transport Inside the Cell – The vesicle moves within the cell for processing.

Question 5

what is Active transport

Answer 5

(Requires Energy, Moves Against Concentration Gradient)

Question 6

What is passive transport

Answer 6

(No Energy Needed, Moves with Concentration Gradient)

Question 7

Explain the steps In passive transport

Answer 7

1. Molecule Movement – Molecules move from high to low concentration naturally.
   
   2. Diffusion or Facilitated Diffusion
      ○ Simple Diffusion – Small molecules pass directly through the membrane.
      ○ Facilitated Diffusion – Larger molecules pass through protein channels.
      Equilibrium Reached – Movement continues until both sides of the membrane have an equal concentration.

Question 8

Explain the steps in active transport

Answer 8

1. Molecule Binding – The molecule attaches to a transport protein in the cell membrane.
   
   2. Energy Use (ATP) – The cell uses energy (ATP) to change the protein’s shape.
   3. Molecule Transport – The molecule is pushed across the membrane, from low to high concentration.
      Release & Reset – The molecule is released inside the cell, and the transport protein returns to its original shape.

Question 9

Define Osmosis

Answer 9

net movement of the solvent through a semi permeable membrane into an area of higher solute concentration , that tends to equalise the concentrations of the solute on both sides

Question 10

Define diffusion

Answer 10

Diffusion – refers to net movement of molecules or atoms from an area of high concentration to an area of low concentration

Question 11

Factors affecting diffusion

Answer 11

• Difference in the gradient
• Surface area
• Thickness of the membrane
• Mass of the particle
• temperature