Download Group 3

Group 1: OSMOSIS
Definition: Diffusion of water across a
selectively permeable membrane (high
to low concentration)
1 Factor that controls osmosis:
concentration gradient-unequal
distribution of particles
#3: water diffusing across a selectively
permeable membrane the number of
sugar molecules did not change on
each side of the membrane but the
number of water molecules on either
side did change.
#4: water moves through or diffuses
from different levels in concentration
through the cellular membrane. almost
all cells are subjected to osmosis
because they are surrounded with
water *** maintains homeostasis
#5: concentration of dissolved
substances in the solution is the same
as the concentration of dissolved
substances inside the cell
Water moves at the same rate in and
out of the cell
Group 2:
1. Hypotonic: concentration of
dissolved substances is lower in
the solution outside the cell, than
the concentration inside the cell.
Hypertonic: concentration of
dissolved substances outside the
cell is higher than the concentration
inside the cell.
2. hypotonic: cells experience
osmosis. Cells are getting larger.
Hypertonic: experience osmosis that
causes water to flow out. Cells are
getting smaller.
3. refer to picture on the board
4. Isotonic stays the same.
Hypotonic gets more water and
has more concentration in the
cell.
Hypertonic has less concentration
in the cell and loses water.
Group 3
1. Passive Transport- movement of
particles across the cell
membranes by diffusion or
osmosis; the cells use no energy
to move the particles across the
membrane.
2. Facilitated Diffusion- passive
transport of materials across a
plasma membrane by transporting
proteins embedded in the plasma
membrane.
3. Channel proteins form channels
to allow only specific substances
to flow through it. Carrier Proteins
change shapes to allow a
substance to pass through the
plasma membrane.
4. Demo= passive transport.
Group 4
1. Active transport is the movement
of materials through a membrane
against a concentration gradient,
requiring energy from a cell.
2. Active transport occurs when a
carrier protein first binds with a
particle of the substance to be
transported. Then the proper
molecule binds with the protein,
chemical energy allows cell to
change the shape of the carrier
protein, so the particle to be
moved is released. [rubber band]
3. Passive transport doesn’t use
energy & active transport uses
energy.
4. Active transport is the materials
being actively transported. This
requires energy because it is not
passive, less work for the cells. It
occurs when unnecessary binding
occurs.
Group 5:
1. Endocytosis Process of cells taking
in substances from low to high
concentration
Exocytosis The expulsion or
excretion of substances from an
area of low concentration to an
area of high concentration.
2. Exoskeleton and Endoskeleton
3. Surface area is how much material
is in contact with the outside;
Volume is the inner content
4. DNA is needed to make proteins
and a large cell would need a lot of
proteins to transport materials and
DNA can only make protein so fast.
Diffusion limits cell size because
since diffusion is slow a large cell
would have to wait for a long time
for the nutrients to reach the
mitochondria.
Surface area-to-volume limits cell
size because when the surface
area increases a little the volume
increases a lot. This means there is
little surface area to absorb all the
necessary substances required to
help the cell function.