Cells

1
Chapter 2 Cells Section 3 Transport in Cells
2
?All living things are made of
matter. ?matter anything that has mass
and takes up space -made from small
particles called atoms
3
?atoms the smallest building
blocks of matter
Ex of atoms C carbon H hydrogen O
oxygen N nitrogen
4
?molecule 2 or more atoms
joined together -always
moving -bounce and change direction -like
ping pong balls bouncing around in
a box EX water
5
A Water Molecule (made of atoms)
2 atoms of hydrogen (H2) 1 atom of oxygen (O)
H
H
O
6
solid
liquid
gas
7
?HIGH Concentration area with
MANY molecules of a substance ?LOW
Concentration area with FEW or NO
molecules of a substance
8
?Transport of Molecules in Cells ?cells must
remain small so it does not take too long to
get nutrients delivered and waste
removed efficiently
9
?cells need to take in nutrients and get rid
of waste to stay alive and to function
properly ?materials can move in/out of a
cell because the cell membrane is
selectively permeable
10
selectively permeable membrane
11
Selectively permeable certain
molecules can pass through it, others
cannot EX a kitchen strainer and window
screen are selectively permeable
12
?Types of Transport in Cells ?Diffusion
(HIGH concentration ? LOW concentration) -Movem
ent of molecules from an area of HIGH
concentration to an area of LOW concentration
(moves across a selectively permeable cell
membrane)
13
-Diffusion is used by cells to take materials
such as oxygen, water and food. -Diffusion is
also used by cells to get rid of waste.
14
(No Transcript)
15
-Diffusion is referred to as
PASSIVE_TRANSPORT because NO energy is used
by the cell to move molecules
?molecules automatically want to spread
out, so they move from HIGH to LOW
concentration
16
EX food coloring in water popcorn
odor/perfume in the air
17
high concentration
low concentration
18
?Types of Transport in Cells ?Osmosis (HIGH
concentration ? LOW concentration) -a special
type of diffusion that involves ONLY
WATER
19
-Osmosis is the movement of WATER
molecules ONLY from an area of HIGH
concentration to an area of LOW concentration
(molecules move across a
selectively permeable cell membrane)
20
Osmosis (water moving from HIGH to LOW
concentration)
21
-Osmosis is also a form of
PASSIVE TRANSPORT because NO energy is
used EX watering a plant
22
osmosis
23
It rains...
24
EQUILIBRIUM (equal)
25
osmosis
26
Transport of molecules within a cell can also
be active. During active transport, molecules
move from LOW concentration to HIGH
concentration. The cell must use energy to do
this. LOW HIGH (like pedaling
UPhill)
27
Passive Transport HIGH to LOW -NO energy
required Active Transport LOW to
HIGH -energy IS REQUIRED
28
(No Transcript)
29
(No Transcript)