MCGB Revision Lecture 1a Flashcards
which cells is the nucleus not found
RBC and platelets
where are pronucleus’ found
ovum and spermatozoa
how big is a nucleus
6nm
how to substances such as mRNA leave the nucleus?
via nuclear pores
- bilayer is very selective
role of nucleolus found at the centre the nucleus
rRNA synthesis and ribosomal subunit proteins
nucleoplasm
cytoplasm of the nucleus
chromatin is found
in the nucleoplasm
heterchromatin (dark)
condensed
euchromatin (white)
non- condensed
where are mitochondria not found
RBC- can only anaerobically respire
–> don’t use the oxygen they are carrying
outer membrane of mtichodnria
smooth
inner membrane of mitochondria called
cristae
- ETC (ATP production)
what happens in the matrix of the mitochondria
link reaction and krebs cycle
link reaction
conversion of pyruvate to acetyl co A
mitochondria has it own
DNA and ribosomes
- endosymbiotic theory
RER and SER present in all cells but
RBC
RER and SER structures
flattened sacs called cisternae
diff between RER and SER
RER around nucleus and SER around RER or in cytosol
function of RER
protein synthesis and packaging into vesicles
function of SER
detoxification, fatty acid synthesis, disulphide bond formation, storage of calcium, cholesterol metabolism
Golgi structure
flattened sacs making up cisternae
cis golgi
incoming vesicles and processing (glycosylation, sulfation, nitrosylation)
Golgi stack
cis, middle and trans cisterna
trans golfi
sorting vesicles and exiting
role of Golgi
- Receiving, processing packaging and shipping of proteins
* Distribute to other organelles or out of the cell by exocytosis
lysosomes not found in
RBC
structure of lysosomes
Single membrane formed from the budding off Golgi apparatus
pH of lysosome
pH5
what are found within lysosomes
Hydrolases – protease, lipase, nuclease and polysaccharidases
function of lysosomes
Cleavage of organic substance and the destruction of dead organelles
lysosome are similar to
peroxisomes formed from the budding of SER. They synthesis bile acids and contain catalases and other oxygen dependent enzymes. They are also found in plant cells
cytoskeleton found in
all cells
- microtubules
- microfilaments
- intermediate filaments
microtubules
- polymers of globular tubulin
- needed for centriole formation in cell division - maintains shape of cell and anchors organelles -form basal bodies to develop motile cilia
microfilaments
- polymers of globular actin
- cell to cell interactions and cells to matrix
intermediate filaments
- fibrous protein
- maintains cell shape and cell to matrix interactions
bacterial cells have both
plasma membrane and cell wall
bacterial cell structures
- capsule
- pili
- flagellum
outer coat of virus called
envelop, covered in envelope proteins
viral genes enveloped in
capsid
what comprises nucleic acid
sugar, phosphate head and base