2a+b- level of organisation & cells Flashcards
5 levels of roganisation in order?
organ system –> organ –> tissue –> cells –> organelles
what is an organasim
living thing that has an organaised structure and completes MR.C. GREN
what is an organ system
a group of organs that work 2gether to complete a function or seriers of .
what is an organ
a group of tissues that work 2gether to complete a function or seriers of
what is a tissue
a group of cells that work 2gether to complete a function or seriers of
what is a cell
the basic membrane bound of the body,
contains the fundamentals fro life ,
made of organelles
what is an organelle
within cells
some = membrane bound (nucleus)
some arent= ribosomes
what is in an animal cell ( 5 )
nucleus, cytolplasm, cell membrane, ribosomes, mitochondria
what is a nucleus
controls all activities
carries genetic material for making new cells
what is cytoplasm
liquid gel where most chem reactions take place
what is cell membrane
controls the passage of substances in and out of the cell
selectively permeable membrane
what is mitochondria
site or respiration, releases energy
what are ribosomes
carry out proetin synthesis
(e.g. they help make enzymes, a very imp protein group
enzymes =-= control chem reactions in cytoplasm
what are in a plant cell (8)
cell walls, chloroplasts, cell membrane, permanenet vacuole, mitochondria, ribosomes, nucleus, cytoplasm
what is a cell wall
made up of tough cells (cellulose)
strengthens cells, providing support
what are chloroplasts
- site of photosynthesis (NOT chlorophyll)
- contains green pigment (chlorophyll)
- chlorophyll -> absorbs light energy
what is permanenet vacule?
- filled w cell sap
- stores= dissolved sugars, mineral ions and other solutes
what are the 3 extras in plant cells?
vacuole, cell wall, chloroplasts
what is the basic formula for calculating magnification, with actual size and image size all subjects.
M= I/A
A= I/M
I= AM
what does M, I, A mean in the eq M= I/A
magnification= image size/ actual size
steps to calculate magnification
- find the largest length on cell,
- convert to micro meters (1 mm = 1000pm )
- use formula
image size = 20 mm
actual size = 10,000 pm
magnification =?
x2 (20,000/10,000)
image size = 200 mm
magnification = x 50
actual size = ?
4mm/4,000 pm
actual size = 10 mm
magni = 5 x
50mm –> 5cm
what are specialised cells
cells taht are adapted to specially fulfil their function, differentiation
how are red blood cells specialsed?
fx = carry o2 around body 2 help tissues do respiration
= bioconcave disc shape, ↑sa, ↑ O2
= no nucleus, ↑ space for o2 + haemoglobin
= flexible 2 travel small spaces
= protein called haemoglobin (binds O2 2 carry out)
how are palaside cells specialised?
fx = 2 absorb light for photosynthesis
= long and thin, ↑ sa exposed 2 light
= ↑chloroplasts, 2 absorb more light
