cell biology 1 Flashcards
what are the features of plasma membranes
- lipid bilayer
- selectivity permeable
key features of the nucleus
- contains chromosomes
- one or more nucleoli
- nuclear envelope
- nuclear lamina
- nuclear pores
what the the key features of ribosomes
- large protein/ RNA complex
- located in the cytosol
- read mRNA to produce proteins
- attached to the eukaryotic ER or prokaryotic PM
what is the smooth ERs function
lipid processing and secretion
what is the rough ERs function
- studded with ribosomes for protein production of:
- membrane proteins
- extracellular proteins
- secretory pathways
what is the function of the Golgi
- exit route from ER in secretory pathway
- carbohydrate and polysaccharide synthesis
- protein glycosylation and sorting
- glycosaminoglycans synthesis
what is the structure and function of lysosomes
- membrane bound organelles
- contain soluble hydrolytic enzymes
- regulate intercellular macromolecule digestion
what are peroxisomes functions
- membrane bound organelles
- perform oxidation reactions using hydrogen peroxide and oxygen
what is the structure of mitochondria
- contains inner and outer membrane
- have their own DNA
- have their own ribosomes
what are the functions of mitochondria
- ATP production
- inner membrane for electron transport chain
- fatty acid beta oxidation
- Ca2+ regulation
what is a tight junction
- seals gaps between epithelial cells
what is a adherens junction
- connects actin filament bundles in one cell with that in the next cell
what is a desmosome
connects intermediate filaments in one cell to those in another
what is a gap junction
allows the passage of small water soluble molecules from cell to cell
what is an actin-linked cell-matrix junction
anchors actin filaments in a cell to extracellular matrix
what is a hemidesmosome
anchors intermediate filaments in a cell to extracellular junction
what are the key features of bacteria cells
- no nucleus - single circular DNA in cytoplasm
- cytoplasm lacks membrane bound organelles
- smaller ribosomes - 70S
- outer membrane -ve
- thick peptidoglycan cell wall +ve
- plasmid DNA
- capsule
- flagella
- surface layer
where did archaea originate from
originally isolated from extreme environments “extremophiles”
what are the features of archaea
- no nucleus - single circular DNA
- cytoplasm lacks membrane bound organelles
- smaller 70S ribosomes
- cell wall contains pseudopeptidoglycan or pseudomurein
- genome is larger and more complex than bacteria
what are viruses and what are their features
- non living particles
- DNA or RNA surrounded by protein or lipid and protein capsid
- replicate in living cells
what are the stages of the cell cycle
- M phase
- G1 phase
- S phase
-G2 phase
what happens in prophase of mitosis
- sister chromatids condense
- mitotic spindle assemble between two centrosomes
what happens in prometapahse
- breakdown of nuclear envelope
- chromosomes attach to spindle microtubules via kinetochores
what happens in metaphase
- chromosomes aligned at equator of the spindle
- kinetochore microtubules attach sister chromatids to opposite spindle poles
