The ultrastructure of a liver cell as an example of an animal cell
- PM: plasma membrane
- M: mitochondria
- rER: Rough endoplasmic reticulum
- GA: Golgi apparatus
- L: Lysosome
- MV: Microvilli
- FR: Free ribosomes
Functions of each of the named structures
- Ribosomes- Main site of protein synthesis
- RER- Packages proteins synthesised in ribosomes
- If you look at the IBDP Biology curriculum, Digest macromolecules and contain digestive enzymes
- Golgi Apparatus- Modifies, stores and routes products of endoplasmic reticulum.
- Mitochondrion- Site of cellular respiration
- Nucleus- Contains cell’s genetic information
Electron micrographs of liver cells
Comparison of prokaryotic and eukaryotic cells
·Always has nucleus with linear DNA (chromosomes) and histones
·Membrane bound organelles
·Cell division by mitosis or meiosis
·Ribosomes are larger (80s)
·Naked loop of DNA
·No membrane bound organelles
·No mitochondria present
·Cell division by binary fission
·Ribosomes are smaller (70s)
Three differences between plant and animal cells
Outline two roles of extracellular components
Referring to the IBDP Biology specification,
- The plant wall maintains shape, prevents excess water uptake, and holds the whole plant up against the force of gravity.
- Animal cells secrete glycoproteins that form the extracellular matrix (ECM). This functions in support, adhesion and movement.
That's the end of this topic.