Cell Structures and Functions Flashcards
What does a typical structure of a bacteria (prokaryotic)?
plasma membrane, cell wall, capsules and slime layers, flagellum, fimbriae, pili, nucleoid, endospore
What does the plasma membrane consist of?
phospholipids and proteins
Does all prokaryotes have a cell wall and what does it do?
yes, support, protection and shape
What does bacteria have in their cell walls?
peptidoglycan
What are capsules and slime layers and what do they do?
sticky layer of polysaccharides or protein surrounding the cell wall (sticking, and prevents dehydration)
What is the flagellum used for?
movement
What are fimbriae?
hair like projections that help stick to things
What are pili?
long projections to trainer DNA between cells
Where is the nucleoid?
in the cytoplasm where the chromosome is
What is the plasmid?
unique to some bacteria where there is DNA separate from main chromosome
What is the endospore and why does it form?
copy of chromosome surrounded by multilayer cell wall; formed for survival in harsh conditions
Is there a presence of a nuclear envelope in bacteria, archaea, eukarya?
bacteria - no
archaea - no
eukarya - yes
Is there a presence of membrane bound organelles in bacteria, archaea, eukarya?
bacteria -no
archaea - no
eukarya - yes
What are the types of membrane lipids in bacteria, archaea, eukarya?
bacteria - unbranched hydrocarbons
archaea - some branched hydrocarbons
eukarya - unbranched hydrocarbons
Is there a presence of circular chromosome in bacteria, archaea, eukarya?
bacteria - yes
archaea - yes
eukarya - no
What are the key structure of the endomembrane system?
nuclear envelope/nucleus
ER
golgi apparatus
lysosomes
vacuoles
plasma membrane
What are the components of the nuclear envelope/nucleus?
envelope - inner and outer membrane
pore - material entry/exit
chromatin - DNA + protein
nucleolus - site of rRNA synthesis
lamins - A+B give structural support to nucleus
What are lysosomes?
membrane bound organelles packed with enzymes (recycling center)
acidic
proton pump
enzymes - hydrolysis of covalent bonds - complex molecules - simpler forms
What is the ER and what is the difference between smooth and rough?
protein traffic, 1 membrane
rough - attached ribosomes, help fold and traffic proteins
smooth - no attached ribosomes, makes lipids, detoxify and metabolize
What are the 3 types of vacuoles and their functions?
food - engulf food or particles
central - plants; site of storage with tonoplast membrane
contractile - single cell - pump out water
What is the function of the golgi apparatus?
modification, packaging, and protein transport
cis face - trans face
what is the function of the plasma membrane?
cell protection
encloses cell
bounds the cytoplasm inside of a cell
what are peroxisomes?
single membraned organelles that uses O2 to create hydrogen peroxide using the hydrogen atoms from organic compounds; the peroxide can then be broken down into water and oxygen; found in liver
What is the mitochondria and chloroplasts?
mito. - double membraned organelle involved in the site of cellular respiration
chloroplast - plant organelle containing an inner/outer membrane, photosynthesis
What is the components/function of the extracellular matrix (ECM)?
structure surrounding animal cells
comprised of proteins
bind to membrane proteins called integrins
changes can cause inner cell changes
What are the 3 components of the cytoskeleton?
microtubules, microfilaments, intermediate filaments
what are microtubules made of/function and examples?
alpha and beta tubulin (tubulin dimer)
maintain cell shape, cell motility, chromosome movements in cell division, and organelle movements
ex. vesicles walking on microtubules, centrosomes and centrioles, cilia and flagella
what are microfilaments made of/function and examples?
actin
maintain cell shape, changes in cell shape, muscle contraction, cytoplasmic streaming, cell motility, and cell division
ex. actin-myosin interactions, ameboid movement, cytoplasmic streaming
what are intermediate filaments made of/function.
proteins of the keratin family
maintain cell shape, anchorage of nucleus and certain other organelles, and formation of nuclear lamina
What are the cell junctions of animal cells and what do they allow pass?
tight - nothing can pass between the cells
desmosomes - some things can pass between the cells
gap - everything can pass between the cells
what are the cell junctions of plant cells and what do they allow pass?
plasmodesmata - channels between plant cells that allow water and nutrients to pass between cells; similar to gap junctions
