Cell biology

eukaryotic cells characteristics

larger in size, unicellular or multicellular, linear DNA, diploid chromosomes, have membrane enclosed organelles, divide by mitosis and reproduce sexually

examples of eukaryotes

animal and plant cells

prokaryotic cells characteristics

smaller in size, unicellular, absent nucleus, DNA is circular, haploid chromosomes, no membrane enclosed organelles, divide by binary fission, reproduce sexually and asexually

examples of prokaryotes

bacteria and archaea cells

double membrane structures

nucleus, mitochondria, chloroplasts

cell wall characteristsics and functions

cellulose and lignin, freely permeable, provides strength, shape and structural support, prevents cell from bursting

plasma membrane characteristics and functions

lipid bilayer with proteins and sterols, semi permeable, controls transport of materials entering and exiting the cell

peroxisome characteristics and functions

contains enzymes that convert hydrogen proxide to water, detoxes alcohol and harmful compounds

mitochondria functions

provides energy via cellular respiration

golgi apparatus functions

modifies and packages proteins and lipids, performs exocytosis

exocytosis

when golgi apparatus sends a vesicle bound protein outside the cell

ribosomes functions

translates mRNA into protein

endoplasmic reticulum functions

synthesises lipids and carbs

rough endoplasmic reticulum functions

modifies proteins, sends proteins to golgi apparatus

chloroplasts functions

site of photosynthesis

cytoskeleton characteristics and functions

microfilaments, intermediate filaments, microtubules, supports the plasma membrane, holds organelles in place

vacuole charcateristics and functions

tonoplast membrane, osmotic regulation, turgor pressure, storage and breakdown of waste products

nucleus characteristics and functions

composed of chromatin, nucleolus, nuclear pores, nuclear envelope, site of DNA and RNA synthesis, processing, transcription

lysosome characteristics and functions

hydrolytic enzymes, self destructs via apoptosis if the cell is damaged beyond repair, digests obsolete components of the cell via phagocytosis

difference between golgi apparatus trans and cis face

the cis face receives materials and the trans face transports materials

sites of transcription in the cell

nucleus, mitochondria, chloroplast