Download The Cell

Do Now
 List
the most important “thing”
you have learned so far in this
class!
 Write at least one question for
Dr. Miller – He is a master
biologist and can answer just
about ANYTHING!
Dr. Miller
American cell biologist and molecular
biologist who is currently Professor of
Biology and Royce Family Professor for
Teaching Excellence at Brown University.
 Miller's primary research focus is the
structure and function of cell membranes,
especially chloroplast thylakoid
membranes.

Objectives
 Review
fundamental concepts about
cells by listing the most important
ideas.
 Complete a biology test to see how
much you have learned so far by
comparing to the baseline.
 Prepare for midterm exam by setting
up studying plans.
This Class (Analogy)
Do Now
 How
will you study for the
midterm?
 What grade do you expect to
earn? How will it affect your
current grade in this class?
Objectives
 Engage
in a discussion with Dr. Miller
and expand on learned biological
concepts by connecting ideas and
asking questions.
 Summarize the main components of
Dr. Miller’s presentation.
The Cell
Review
http://www.comedycentral.com
/video-clips/vxg0ck/comedycentral-presents-paper-trail
Cells
Marks the boundary between the “living
and the dead”
 Structural and functional unit of an
organism
 Smallest structure capable of performing
all of the functions necessary for life

What is a cell?

Why do we care?




We have TRILLIONS of them!! (@65)
Every organism is composed of
one or more cells
Basic unit of structure and
function in organisms
All come from pre-existing cells
Cell Theory
All cells…….
Have an outer plasma membrane
 Contain DNA



Enclosed within the cell somewhere
Contain cytoplasm
Plasma Membrane and Cytoplasm


All cells surrounded by a
plasma membrane
 Phospholipid bilayer
material inside a cell is
the cytoplasm
 Everything between
the plasma
membrane and the
region of DNA
 Gives cells their
shape
 Assist in movement
of cell and organelles
Microscopes

Compound light
microscope

Multiple lenses increase
magnifying power
Two basic kinds of cells

Prokaryotic


Nothing separates the
DNA from
internal cell parts
Eukaryotic


Contain organelle sacs
Nucleus – contains the
DNA
Eukaryotic Cells
Examples of Eukaryotic Cells:
Animal
 Plant
 Fungi
 Protozoa

Cell Walls

Plant cells



Permeable
Protective
In addition to a plasma
membrane
Organelles

Organelles act as their own separate
“organs”


They physically isolate chemical reactions
inside cells
Animals and plants will differ in their
organelles
Nucleus



Encloses the DNA of a
eukaryotic cell
Contains chromosomes
Functions:
 Prevents DNA from
getting entangled with
structures in the
cytoplasm
 Outer membranes act as
a boundary
Components of the nucleus
Nuclear pores
 Nuclear envelope
 Nucleolus
 Nucleoplasm
 DNA



Chromosomes
Chromatin
Nuclear envelope



Double-membrane
system composed of lipid
bilayer (with pores)
Bilayers surround the
fluid part of nucleus
(nucleoplasm)
Continuous with the
endoplasmic reticulum
Nucleolus


Dense mass located
within the nucleus
Produces ribosomes
Ribosomes

Site of protein
synthesis



Occurs in the cytoplasm
Attached to the
endoplasmic reticulum
Differ between
prokaryotes and
eukaryotes

Why is this important
from a health aspect?
Endomembrane System

Helps modify proteins into final form

Lipids are assembled
Compartmentalizes the cell
 Main components:





1.
2.
3.
4.
Nuclear envelope
Endoplasmic reticulum (ER)
Golgi body
Various vesicles (transport)
1. Nuclear envelope


Merges with the
membrane of the ER
Consists of
membranous channels
and saccules
2. Endoplasmic Reticulum



Channel that snakes
through the cytoplasm
Lipids assembled and
polypeptide chains modified
into final proteins
Can be rough or smooth


Dependant on the
attachments of ribosomes
Rough ER


Processing and
modification of proteins
Smooth ER

Synthesizes phospholipids
3. Golgi Body (Apparatus)



Series of flattened
sacs
Collects, sorts,
packages, and
distributes materials
such as proteins and
lipids
Contain enzymes
that put the finishing
touches on proteins
and lipids
4. Vesicles

Enzymes from golgi apparatus sort and
package the molecules into vesicles



Tiny sac that moves through cytoplasm
Function in transport, storage, or digestion of
substances
Two main types:


Lysosomes
Peroxisomes
Lysosome

A lysosome is a
membrane-enclosed sac

contains digestive
enzymes to break down:


Macromolecules
damaged organelles
Put it all together……
Energy-Related Organelles

organelles specialize in
converting energy to a
form that can be used
by the cell



Chloroplasts



Requires solar energy
Dissipates as heat
Use solar energy to
synthesize carbohydrates
Carbohydrates then
broken down in the…..
Mitochondria

Produce ATP molecules
Energy-Related Organelles

Photosynthesis

Cellular Respiration

The chemical energy of
carbohydrates is
converted at ATP
Cytoskeleton:
Cilia and Flagella - Movement




Hairlike projections
Help in the movement
of cells
Some examples….
Why would we need
them?
Vacuoles

Membranous sacs


contractile vacuoles of protists
central vacuoles of plants
Prokaryotes
Archae
Bacteria
Prokaryotic Cells

Cell Wall
Capsule

Flagellum

Plasma membrane

Nucleoid

Plasmids

Ribosomes
