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MOVEMENT ACROSS THE PLASMA MEMBRANE
1. Three types of passive transport. Simple diffusion
Osmosis
Facilitated diffusion
2.TRANSPORT
Active Transport
Passive Transport
o Simple Diffusion: The movement of molecules from region of
high
concentration to low concentration.o The movement of molecules
from region of high concentration to
a region of low concentration with the help ofcarrier proteins.o
Osmosis: The movement of water molecules from dilute solution
to a concentrated solution across a Semi permeable membrane.
3. The figure below shows the model of the plasma membrane.
Label L, M, N,and O shows four types of nutrients. P1, P2 and P3
show three types of protein.
(i) Name the processes labelled L, M, N,
O.L:SimplediffusionM:FasilitateddiffusionN:Fasilitateddiffusion
http://1.bp.blogspot.com/_vK2Yw79fUBk/S6pM8W_XLQI/AAAAAAAAAic/8RJmAoDTUeY/s1600/molecules+transported.GIF
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O:Activetransport
(ii) Name the protein labelled P1, P2 and
P3.P1:PoreproteinP2:Carrierprotein
P3:Carrierprotein
(iii) State two characteristics of the molecules that are
transported into thecellbyprocessL.1.Small2.Solubleinlipid
4. The figure shows a model of the active transport system that
depends onseveral carrier proteins found in the cell membrane.
(i)
Explain:whatdoyouunderstandbyactivetransport.Movement of
particles across the plasma membrane
1. by carrier proteins,2. against the concentration gradient
and3. requires energy.
(ii) Give an example of active transport in plants.Ion or
mineral uptake by plant root hairs.
(iii) State two differences between active transport and
diffusion.Any two differences energy, gradient concentration,
living membrane.
5. The table below shows the effect of hypotonic, isotonic and
hypertonicsolution on spinach strips, red blood cells and plant
cells.
http://2.bp.blogspot.com/_vK2Yw79fUBk/S6pVdGQZJyI/AAAAAAAAAik/Dhic71ff_D0/s1600/active+transport+system.GIF
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Hypotonic solution Isotonic solution Hypertonic solution
Spinach strip in distillwater
Distill wateris hypotonic compared tothe cell sap.
Waterenters into spinach cellthrough cut surface byosmosis .
Epidermis is
water proof.
Theepidermis layer curvedinward.
Spinach strip in 5% sucrosesolution
The rate of waterentering and leaving thespinach cell through
semipermeable mambraneis the same.
The shape of spinach strip remains thesame
Spinach strip in 30% sucrosesolution
Red blood cell in distillwater.
Red blood cell in isotonicsolution
Red blood in 30% sodiumchloride solution
Plant cell in distill water Plant cell in isotonic solution
Plant cells in 30% sucrosesolution
http://4.bp.blogspot.com/_vK2Yw79fUBk/S6pZUm_11nI/AAAAAAAAAjE/jhWBgmiDfnA/s1600/plant+cell+sucrose.GIFhttp://3.bp.blogspot.com/_vK2Yw79fUBk/S6pZUFWKZhI/AAAAAAAAAi8/nvPM7hRpKwE/s1600/red+blood+cell+isotonic.GIFhttp://2.bp.blogspot.com/_vK2Yw79fUBk/S6pZT4bms5I/AAAAAAAAAi0/7HAfcocqmlE/s1600/spinach+sucrose.GIFhttp://2.bp.blogspot.com/_vK2Yw79fUBk/S6pZTbqw4VI/AAAAAAAAAis/Ys4SUpZsjPg/s1600/spinach+distill+water.GIF
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