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
what happens in anaphase
- sister chromatids separate to form two daughter chromosomes
- they are pulled towards spindle poles
- kinetochore microfibrils get shorter and spindle poles move apart
what happens in telophase
- daughter chromosomes arrive at poles and decondense
- nuclear envelope reassembles around each set
- end of mitosis
- contractile ring starts to contract
what happens in cytokinesis
- cytoplasm is divided into two by a contractile ring of actin and myosin
- two daughter cells are created
what are the stages of meiosis
1) prophase
2) prometaphase
3) metaphase
4) anaphase
5) telophase
6) metaphase 2
7) anaphase 2
8) telophase 2
what Is a diploid cell
have chromosome pairs
what is a somatic cell
genetic information not passed onto offspring
what is a germ-line cell
genetic information passed onto offspring
what is a haploid cell
has one set of chromosomes
what is a totipotent cell
able to produce any type of body cell aswell as the placenta
what is a pluripotent cell
able to produce nearly every body cell apart from placenta
what is a multipotent cell
can differentiate into many different body cells
what is a oligopotent cell
can only differentiate into a few different body cells
what is a unipotent cell
can only differentiate into one type of body cell
