Download Cell Structure and Function

10-22-10
• In
• Rewrite your hypothesis from the
“Eggs-periment”
10-22-10
• Through
• Quiz
• Cell notes
• OUT
• NONE!!
Missed questions
• 1. Natural selection causes
• A. Increase in the frequency of certain traits
within a population
• B. Mutations in the DNA sequences of genes
within organisms
• C. Changes in the non-living environment
• D. The formation of fossils
Missed questions
• 2. New species form ______
a. When organisms die and become
fossilized
b. When members of two different species
come together and mate to form a new
species
c. As a result of natural selection over
geologic time
d. Directly as a result of changes in their
genes
• 3.
The drug penicillin is used to kill bacteria. In the
lab, you expose 1000 individual bacteria to penicillin
and it kills 996 of the original bacteria. The four
bacteria that survive were exposed to the penicillin
again. Which of the following statements is true?
• A. The bacteria that survived could resist penicillin before the
drug was delivered
• B. The bacteria that survived reproduced faster than the other
bacteria
• C. The bacteria that survived changed themselves to be able to
resist penicillin.
• D. The bacteria that survived learned how to resist penicillin
• 4. Group 1-spider, tiger, jellyfish,
earthworm, dog, clam, hawk
Group 2—oak, tomato, redwood, cactus, wheat,
apple, tree
Group 3—mushroom,mold,mildew, yeast
The three groups represent different _______
a. Species
b. Families
c. Kingdoms
d. classes
Cell Structure and Function
Cell organelles and what they do,
from the outside in!
• Lipids
• Lipid bilayer
• Protein molecules
-fat molecules
-cell membrane
fat molecules
arranged
in 2 layers prevents
water soluble
molecules
from passing
-receptor proteins,
allows specific
molecules to move in or out
of a cell
adhesio
n
protein
passive
transporte
r
recogniti recepto
on
r
protein protein
lipid
bilayer
cytoskelet
al
proteins
active
transporter
(calcium
pump)
cytoplasm
active
transporter
(ATPase
pump)
Cell Membrane
• The cell membrane consists of a
phospholipid bi-layer in which proteins
are embedded to varying degrees.
• Hydrophilic phosphate heads point
toward the outside of the cell, while the
hydrophobic lipid tails point inward
toward the nucleus of the cell.
Cell membrane
The structure enveloping a cell,
enclosing the cytoplasm and forming a
selective permeability barrier. It is
inside the cell wall in plant cells, while it
is the only barrier between the outside
of the cell and the cytoplasm in animal
cells
Cell membrane
Phospholipid bilayer with
embedded protein
Plants have cell walls
attached to their cell
membranes
Cytoplasm
• Cytoplasm is a gelatinous, semitransparent fluid that "fills" most cells.
• It contains all cell organelles except the
nucleus and the cell membrane.
• All the functions for cell expansion,
growth and replication are carried out in
the cytoplasm of the cell
Mitochondria
• Mitochondria are sometimes described
as "cellular power plants," because they
generate most of the cell's supply of
ATP, used as a source of chemical
energy.
Mitochondria
Golgi apparatus
• The primary function of the Golgi apparatus is
to process and package proteins synthesized
by the cell (In the Endoplasmic Reticulum.)
• Some of these will eventually end up as
integral membrane proteins embedded in the
cell membrane.
• Other proteins moving through the Golgi will
end up in lysosomes.
• Some proteins will be excreted by exocytosis.
Golgi Apparatus
Endoplasmic Reticulum
• The endoplasmic reticulum (ER) is
responsible for the production of the
protein and lipid components of most of
the cell's organelles.
• The ER contains a great amount of
folds - but the membrane forms a single
sheet enclosing a single closed sac.
Endoplasmic Reticulum
Nucleus
• The nucleus contains most of the cell’s
genetic material in the form of DNA.
• DNA is stored in structures called
genes.
• Genes make up structures called
chromosomes.
Animal cell with nucleus
Close up of nucleus
• Nucleolus and nuclear pores are shown.
Cell Processes
Passive transport
Passive transport is a means of
moving substances across the cell
membrane. Unlike active transport, this
process does not require energy. Two
main kinds of passive transport are
diffusion and osmosis.