B2.2 Organelles and Compartmentalisation

Question 1

Definition of an Organelle

Answer 1

Structure within a cell that performs specific functions

Question 2

Definition of Compartmentalisation

Answer 2

Organisation of ddifferent functions and processes within specific areas of structures within the cell that are seperated by plasma membranes

Question 3

Function of Compartmentalisation

Answer 3

1. Cell can seperate chemical reactions and other cellular processes which allows cells to increase rate of chemical reactions
2. Allows specific reactions to occur in specific places

Question 4

Single Membrane Bound Organelles

Answer 4

Vesicles, Vacuoles, SER, RER, Lysosome, Golgi Apparatus

Question 5

Double Membrane Bound Organelles

Answer 5

Nucleus, Mitochondria, Chloroplast, Chromoplast, Amyloplast

Question 6

Function of Lysosomes

Answer 6

Degrades cytoplasmic components

Question 7

Function of Chromoplasts

Answer 7

Stores and synthesises pigments

Question 8

Function of Amyloplasts

Answer 8

Stores and synthesises starch

Question 9

Non Membrane-Bound Organelles & Do not have a specific function

Answer 9

Cytoskeleton, Cell Wall, Cytoplasm

Question 10

Non Membrane-Bound but have a specific function

Answer 10

Ribosomes, microtuble, centriole, proteasome, nucleolus

Question 11

Function of Proteasome

Answer 11

Degardes targeted cellular protein

Question 12

Advantage of seperation of nucleus and cytoplasm

Answer 12

1. Cytoplasm is responsible for metabolic processes and translation of mRNA into proteins in ribosomes
   - Prokaryotic cells: Transcription and translation occur in the cytoplasm
   - Eukaryotic cells: Post-transcriptions modification, mRNA produced in the nucleus needs to be changed by removing pieces of MRNA. Compartmentalisation allows post transcriptional changes to occur before translation
2. Allows cytoplasm to send signals to the nucleus
   - Message passed on to nucleus to change gene expression through increased or decreased transcription which allows the cell to produce different amounts or types of protein to adjust different conditions

Question 13

Explain the advantage of compartmentalisation of cytoplasm with Lysosome and Phagocytic vacuoles

Answer 13

• Microphages use phagocytic vacuoles joined by lysosomes to break down pathogens into parts which is used to develop an immune response
• Breakdown of waste by the lysosome requires enzymes which could be damaging to other parts of the cell
• Isolating enzymes in phagocytic vacuoles protects the rest of the cell and allows waste to be broken down safely and can use required enzymes in a smaller space which allows for faster and more efficient reaction