Cells Flashcards
What organelles can be seen under electron micrographs?
ER, mitochondria, golgi body, ribosomes
Function of cell membrane
- partially permeable
- controls movement of substances entering or leaving the cell
Function of nucleus
- contains chromatin
- controls cell activities
Function of cytoplasm
- most cell activities occur here
- contains organelles
- site of anaerobic respiration
Function of RER
- ribosomes: sites for protein synthesis (transported out of cell)
- transports proteins to GA for secretion out
Function of SER
- synthesises substances such as fats & steroids
- involved in detoxification
Function of Golgi apparatus
“Majulah SingaPura”
- modifies, stores & packages substances into vesicles for secretion out of cell
Function of mitochondria
- carries out aerobic respiration, glucose oxidised to release energy
Function of cell wall
- only found in plants
- protects cell from injuries
- gives cell a regular shape
Function of chloroplast
- found in plants only
- contains chlorophyll
- absorbs light for photosynthesis
function of vacuoles
A: many small ones storing food and water
P: one large central storing cell sap
Compare the structure of an animal and plant cell
3CV
chloroplast: present in P, absent in A
cell wall: present in P, absent in A
cell membrane: present in P & A
vacuole: large in P, small in A
S - F (Root hair cell)
S: long, narrow extension
F: increases S.A. to V. ratio for faster rate of absorption of water and mineral salts
S - F (RBC)
S: contains haemoglobin
F: combines with oxygen to transport from lungs to all cells
2S: biconcave disc shape
2F: increasing S.A. to V. ratio to absorb and release oxygen faster
S - F (xylem vessel)
S: empty lumen
F: reduce resistance to water flowing
2S: walls thickened with lignin
2F: prevent collapse, provide support
