Transcript AS Biology - Teachnet UK

AS Biology
This is a product of the science
department of Dartford
Technology College
Endoplasmic Reticulum
• Hen+ Dough + Plaice + Mike + Wreck +
Tickle + Hem.
• Complex system of sheet like double membranes
continuous with the nuclear membrane
• Two types of ER –
– smooth – has no ribosomes attached (RER)
– rough – has ribosomes attached (SER)
Golgi Body
• Goal + Guy + Body
• Formed from small pieces of rough ER
which form small vesicles which join to
make a Golgi body
My
Mitochondria
• My + Toe + Con + Dry + Hair.
• Relatively large organelle
• Rod/sausage shaped – 1um – 5um
• Have a double membrane
– The outer controls the entry & exit of
materials
– Inner has many folds called cristae
Centriole
• Cent + Tree + Hole.
• Two short bundles of hollow cylinders
(microtubules) positioned at right angles to
each other
• Found just outside the nucleus in a clear
area of cytoplasm called the centrosome
• Wall of each centriole is made of 9 triplets
of tubes arranged at an angle
Ribosome
• Rye + Bows + Home.
• Small dense structures found in huge
numbers.
• Can be attached to the rough ER of
floating in the cytoplasm.
• Are about 20 – 25 nm in diameter in
eukaryotic cells and slightly smaller in
prokaryotic cells
ER
Chloroplast
• Claw + Row + Plaster + (take away ER)
• Found inside photosynthetic tissues of
plants (abundant in palisade mesophyll
cells of leaves)
• Flat discs 2-10 um in diameter & 1um thick
• Have a double membrane called the
chloroplast envelope
• Inner membrane folded into a series of
lamellae
Nuclear Envelope
• Nuclear (bomb) + Envelope.
• The nucleus is surrounded by a nuclear
membrane / envelope
• Double membrane – outer is continuous
with the ER
• Nuclear pores in the membrane allow the
passage of large molecules in & out (eg
messengerRNA)
Nucleolus
• New + Clay + Hoe + Lass.
• A spherical structure called the nucleolus
is found in the nucleus – this makes
ribosomal RNA and assembles the
ribosomes.