module 2.1 Flashcards
plasma membrane?
phosolipid by layer that controls entry/exit.
nucleus?
- has a nucleolus (contains RNA & makes ribosomes)
- MRNA leaves through pores
- nuclear envelope
- nuclear pores (substances to enter/leave)
- inside nucleus= chromatin (chromosomes) found here
RER?
- doubler membrane with cisternae for transporting molecules
- contains ribosomes for protein synthesis
SER?
-synthesise cholesterol and lipids
Golgi?
- receives proteins from ribosomes in a vesicle(small membrane sac)
- proteins are folded, processed & sent to membrane in vesicle.
Lysosomes?
-bind to old organelles & pathogens to release enzymes and digest them.
Centriole?
- animal cells only
- involved in cilli & pseudopodia formation (2.5)
- involved in cell division (2.6)
mitochondria?
- site of aerobic respiration
- membrane bound organelle
what are the 3 plant only organelles?
cell wall, permanent vacuole, chloroplasts
PLANTS ONLY- chloroplasts?
- site of photosynthesis
- membrane bound organelle
- high internal surface area for photosynthesis
PLANTS ONLY-permanent vacuole?
- membrane bound( called tonoplast)
- contains sap
- maintains turgidity (firmness)
PLANTS ONLY- cell wall?
- made out of cellulose(sugar)
- protects the cell
what is the cytoskeleton?
a collection of filaments and tubules that give the cell its shape and structure + allows movement within a cell
state necessary things about microfilaments
polymers of actin
provide shape and structure
very small
7nm diameter
state necessary things about microtubules
polymers of tubulin
provide a transport network for KINESINS( motor proteins) to pull vesicles + organelles around the cell
used in mitosis and flagella
18-30 nm
what is a stage micrometre
standard sized ruler to calibrate microscopes
what is an eye graticule
standard sized ruler in the eyepiece that remains in focus at all times. used for measuring cells.
compare eukaryotic cells and prokaryotic cells (6)
eukaryotic: \_\_\_\_\_\_\_\_\_\_ true nucleus membrane bound organelles(eg golgi) larger (usually) animal/plant/fungi/protists
Prokaryotic \_\_\_\_\_\_\_\_\_\_ no nucleus no membrane bound organelles smaller bacteria+archea
prokaryotic cells:
pilli?
attaching to other surfaces or cells
~prokaryotic cells:
plasma membrane
~surrounds cytoplasm
prokaryotic cells:
no nucleus/ loose dna
continuous loop, no histones
prokaryotic cells:
ribosomes
smaller
no rer
prokaryotic cells:
cytoplasm
no cytoskeletal structures
prokaryotic cells: wall around it name??
peptidoglycan wall (protein)
prokaryotic cells: plasmids?
small circle of genetic material
prokaryotic cells: flagellum
mobility
name all the structures in prokaryotic cells:
- pilli
- no nucleus, loose DNA
- cytoplasm
- plasma membrane
- ribosomes
- plasmids
- flagellum
- no membrane bound organelles
- peptidoglycan wall (protein)
- protective waxy capsule surrounding cell wall
how can bacteria pass on genetic material between organisms? (1)
pilus draws bacteria together
how can bacteria pass on genetic material between organisms? (4)
plasmids can be passed from one bacterium to an adjacent bacterium. This naturally occurring phenomenon allows beneficial traits to spread quickly.
-used to produce desired proteins
what is the Endosymbiotic theory
explains how early eukaryotic cells consumed respiring bacteria+ photosynthesising bacteria for mutual benefits.
what is millimetres to micrometres?
1mm= 1000um
what is micrometres to nanometers?
1um=1000nm
coordination between organelles- state how proteins are made
- a gene is copied into a molecule of MRNA (messenger RNA). This is called TRANSCRIPTION.
- the mRNA leaves the nucleus via a pore and travels to the ribosome on RER.
- The mRNA is read by a ribosome in triplet code to make a primary structure protein, this is called TRANSLATION.
- The primary structure protein is budded off the RER in a vesicle and moved to the golgi body.
- At the golgi, the primary structure proteins are folded into secondary/tertiary/quaternary structure formation. Other components are added to the protein.
- The finished protein is budded off the golgi into a vesicle and moved to the plasma membrane.
- Vesicle merges with plasma membrane and the proteins released from the cell. This is called EXOCYTOSIS.
Coordination between organelles:7 steps of making proteins
- A gene is copied into a molecule of mRNA(TRANSCRIPTION)
- The mRNA leaves the nucleus via a pore and travels to the ribosome on RER.
- The mRNA is read by a ribosome in triplet code to make it a primary structure protein.
- The primary structure protein is budded off the RER in a vesicle and moved to the Golgi body.
- At the golgi, the primary structure protein is folded into secondary/tertiary/ quaternary formation.
- The finished protein is budded off the golgi into a vesicle and moved to the plasma membrane.
- Vesicle merges with plasma membrane and the protein is released from the cell (EXOCYTOSIS)
state general things about optical microscopes… red and mag included
rely on lenses to focus a beam of light. mag up to x1500. and res (0.2um)
advantages of optical microscopes
cheap, easy to use, specimen can be alive
disadvantages of optical microscopes
low mag, low res
advantages of tems
high level mag/res
fine detail can be observed
disadvantages of tems
large, expensive, specimens have to be dead. skills and training needed.
advantages of sems
3D image given, high mag, depth of field given
disadvantages of sems
black and white image, expensive, large, specimens have to be dead
how do laser scanning microscopes work
use laser light to scan an object point by point and assemble it by computer
advantages of laser scanning microscopes
can focus on structures at diff depths within a specimen so can observe whole living specimens
disadvantages of laser scanning microscopes
costly, relatively small field of vision
state 4 similarities and differences between bacterial cells (prokaryotes) and fungal cells (eukaryotes)
- both have ribosomes in the cytoplasm
- only fungi have a membrane bound nucleus
- bacteria have plasmids, fungi do not.
- both have cell walls. Fungal is made of CHITTIN and bacteria is PEPTIDOGLYCAN.
uses of light microscope, TEM, SEM, laser scanning!!
light microscope- whole cells and tissues
TEM- organelles
SEM- cell surfaces
laser scanning- an object at a certain depth within a cell
resolution and magnification of:
light microscope;
TEM;
SEM;
light microscope; x1500 |200nm (0.2um)
TEM; x500000 | 0.2nm
SEM; x100000 | 0.2 nm
how do you find the value of one eyepiece division
1000/total magnification =___um
why do specimens need to be stained
to make them visible, to increase contrast
2 processes inside cells that rely on cell movement
- chromosomes in cell division
- exocytosis
