Download Cell structure

Cell Structure and Function
1665 Robert Hooke coined the term “cells”
1668 Anton Van Leeuwenhoek
Cell Theory
1830 Schleiden and Schwann
All living things are composed of cells
Cell is the basic unit of life
1850s Virchow
All cells come from pre-existing cells
What are some general
characteristics of all cells?
1. Plasma membrane
2. Genetic information (DNA)
3. Chemical reactions
4. Cytoplasm- all material inside the P.M. and
outside the nucleus which includes water, salts,
and organic molecules. (Some cell’s cytoplasm includes
organelles).
What are the two major types
of cells?
1. Prokaryotic cells (no nucleus)
BacteriaStrep, Staph, and Cyanobacteria
Archaea- prokaryotes such as those that live
in extreme habitats
2. Eukaryotic cells (have a nucleus)
“Protists”, Fungi, Plants, and Animals
Eukaryotic Cell (Animal Cell)
A. Nucleus
The control center of the cell
What does a nucleus contain?
Chromatin - DNA and Protein
Nucleolus – is where ribosomes are made
B. Ribososmes
Sites of protein synthesis
Two Types of Ribosomes
1. Free RibosomesThe proteins made here will function
as enzymes within the cytosol
2. Bound RibosomesAttached to Rough ER
The proteins made here will become lysosome
enzymes, membrane proteins, or secretory
proteins
C. Endoplasmic Reticulum
Network of membranes forming
interlocking channels
Two Types of ER
1. Rough ER (contains ribosomes)
Involved in protein synthesis, membrane
production, and transporting.
The proteins made here will become lysosome
enzymes, membrane proteins, or secretory
proteins
Endoplasmic Reticulum
Two Types of ER
2. Smooth ER
Involved in lipid and carbohydrate synthesis
In the liver it helps detoxify drugs.
Endoplasmic Reticulum
D. Golgi Complex
Stacks of flat membrane sacks
The cell’s warehouse or Post Office
Stores, modifies, packages, and distribute
molecules
Vesicles – are small sacks of membrane
Golgi Complex
(The Cell’s Distribution Center)
Flow of protein within cell
Name a protein that
you want to build.
Remember it starts with DNA
DNA
RNA
Protein
Nucleus
Rough ER
Vesicle
Golgi Complex
Vesicle
Plasma
Membrane
E. Lysosomes serve as the
cell’s digestive system
Lysosomes are vesicles that contain digestive
enzymes
Function: digest individual molecules such as
proteins, fats, and carbohydrates as well as
complete microorganisms and defective
organelles.
What are some examples of how
lysosomes are used?
The Cell’s Powerhouse
F. Mitochondria are these oval, round, or
tubular organelles made from a double
membrane system.
Inner and outer membrane
Cristae- formed from folding of inner
membrane
Matrix- inner space that contains enzymes
that break down food molecules
Sites of aerobic respiration
Mitochondrion
(The Cell’s Powerhouse)
The Cell’s Organizer
The Cytoskeleton is a 3-D network of 3
different protein filaments that is responsible
for the shape, internal organization, and
movement of a cell.
The 3 types of filaments
Microtubules- guide vesicles through the cell
and help form cilia and flagella. VIDEO
Microfilaments - help Amoeba and WBCs
crawl and cause muscle cells to contract
VIDEO
Intermediate filaments- networks of these
filaments help determine a cell’s shape
Locomotion
Immune Response showing macrophages in action
How are plant cells different?
Cell wall
Chloroplasts
Central vacuole
A Plant Cell is a Eukaryotic Cell
Chloroplasts are plastids that
contain the green pigment
chlorophyll and are the sites of
photosynthesis.
Internal structure of chloroplasts
Thylakoids contain chlorophyll
which traps light energy
Stroma is the fluid filled space
w/in the chloroplast where CO2
is converted into glucose
Chloroplast
Other plastids include:
Amyloplasts- stores starch
Chromoplasts- synthesize and
retain yellow, orange, or red
pigments
Vacuoles
Animal cells have vacuoles that
are mainly used for storage of
food and are often temporary.
Plant cells have large central
vacuoles that may occupy 50-90%
of the cell interior.
Functions of the central vacuole
Maintain the cell’s water balance
Turgor pressure- the pressure of
the water w/in the CV pushes
the cytoplasm against the cell
wall.
Storage: pigments, ions, proteins,
and poisons for defense
Disposal of metabolic waste
(toxins)
Central Vacuole