Transcript Cell - Mrs. Blackmon`s Science Blackboard

Cell
Structure
and
Function
Review: Define the following terms.
1. Cyte = cell
2. Cytology - Study of cells
3. Histo = tissue
4. Histology - Study of tissue
5. Cell - Units of structure and function in
living things
Cells are the
smallest unit that
can perform all life
processes. (units
of structure and
function)
The
Discovery
of Cells
Anton Van Leeuwenhoek
• Anton van
Leeuwenhoek was a
Dutch lens maker.
• He developed the
first microscope and
viewed living cells.
Robert Hooke
• Robert Hooke
named cells after
the cork he saw.
• It was dead and
empty.
Schileiden All plants are
made of cells.
Schwann All animals
are made of
cells.
Virchow Cells come
from other
cells.
The work of these men is summarized into
the cell theory.
1. All organisms are composed of cells.
2. Cells are the basic units of structure
and function.
3. All cells come from preexisting cells.
4. Cells contain hereditary material (DNA).
Metabolic Processes of Cells
• These processes occur simultaneously
within all cells.
1. nutrition - food for energy and growth
2. digestion - breakdown of molecules by
enzymes and water, hydrolysis
3. absorption - taking in of vital substances
(water, food, ions, oxygen, vitamins)
4. biosynthesis - building of new compounds
5. respiration - combining glucose and
oxygen to release energy for the cell
- an exchange of gases
6. excretion - elimination of dissolved waste
7. secretion - discharge of cellular products
8. response - reacts to a stimulus
9. movement - flow of content, contraction,
locomotion
10. reproduction - sexual by combining egg
and sperm to form a zygote
- asexual by cellular division
Kinds of Cells
1. prokaryotic cells cells without a nucleus
pro = first, before
karyote = nucleus
Organisms with a prokaryotic cell are
called prokaryotes.
ex: eubacteria – the
true bacteria
Archaebacteria
2. eukaryotic cells – cells with a nucleus
eu = true
karyote = ?
Organisms with
eukaryotic cells are
known as eukaryotes.
• animals
• plants
• fungi
• protists
Plant Cells
Animal Cells
Cells vary in size.
• Most cells are too small to be seen with
the naked eye.
A cell’s surface area-to-volume ratio limits
the size of a cell.
3 Main Parts of Eukaryotic Cells
1. Cytoplasm
• between nucleus
and outer
membrane
• houses organelles
• semifluid with
water, salts, and
organic molecules
Video:
http://vimeo.com/26915500
• ctyoplasmic streaming - moves materials
throughout the cell
2. nucleus
• controls cellular
activities
• transmits
hereditary
material
Parts of the Nucleus
 nuclear membrane surrounds and has
nuclear pores
 nucleolus –
spherical body which
produces ribosomes
 chromatin –
DNA, hereditary
material
3. cell membrane
• separates cells from
surrounding fluid
• selectively permeable
(semipermeable)
• regulates what enters
and leaves the cell
• structure - Fluid Mosaic Model
• double layer of phospholipids with proteins
embedded
Cell Wall
• found in plants,
algae, fungi,
bacteria
• Rigid; protects and
supports
• contains cellulose
for structure
• surrounds cell
membrane
Cell
Membrane