Download cell-discovery-notes-1

Warm –up 1. Where does life come from????
Explain.
2.
2.
What are living things made of?
Can life be made from nonliving things?
Where does life come from????
Life comes from life.
Back in the old days, scientists believed life
came from nonliving things- spontaneous
generation
Aristotle- believed dirty clothes + dark
corner= mice
Others- horse hairs +stagnant water = snakes
Dead meat= maggots- most popular
support for spontaneous gen.
Frances Redi did not believe in spontaneous
generation and chose to disprove the idea of
spontaneous generation through a controlled
experiment.
Cell History & Structure
Standard: Students will analyze the nature of
the relationship between structures and
functions in living cells.
EQ: What is the Cell theory?
RECAll the Characteritics of Life…
 All living things are made up of cells
 The cell is the basic unit of structure and
function in living things much like an atom is
the basic unit of matter
Cell- basic unit of structure and function in an
organism.
Cell Discovery
1st lenses used- 1500s (simple microscope)
Compound microscope invented- 1590- led to
discovery of cells
1663- Robert HookeCut thin slices of plant tissues
Observed thin slices of cork from tree under
compound microscope he made himself
- noticed small rectangular chambers and
named them “cells”
1600s- Anton van Leewenhoek- 1st person to use
simple microscope to study nature.
- he found tiny organisms in pond water
“animalcules”
- made detailed drawings
- looked at teeth scrapings and noticed tiny
organisms- now we know as
bacteria
These discoveries led to new discoveries about
cells….
1833- Robert Brown discovered the nucleus
1834- Schleiden concluded plants are made of
cells
1839- Schwann- all living things made of cells
1855- Virchow- noticed cell reproduction
“All cells come from cells”
All Discoveries led to the Cell Theory- All living things are composed of cells
- Cells are the basic unit of structure and
function in living things
- All cells are produced from other cells
http://rap.stevius.com/ Cell
Theory Rap
Hierarchy/Levels of
Organization in Living Things
Atom
Elements
Tissues
CELLS
Organs
Systems
Ecosystem
Macromolecules
Organelles
Complex organisms
Community
Biome
Population
Biosphere
Basic Cell Structure
1. cell membrane- thin, flexible barrier around cell
2. cytoplasm- gel-like fluid between cell membrane and nucleus
3. nucleus- contains genetic material and controls cell activity
Unicellular- single-celled organisms
Multicelllular- organisms composed of many cells.
Cell Types:

Cells vary in size… from 0.2 micrometers to
the biggest bird egg yolk

There are 2 types of cells…
OBSERVATION- On your own paper, list
similarities and differences you can describe from
the drawings below-

PROKARYOTIC – NO nucleus
 No membrane-bound organelles
 Evolved first
 smaller and simpler than
eukaryotes.
 Ex: All bacteria are prokaryotes
 Escherichia coli, which live in your
intestines
 Staphylococcus aureus, which can
cause skin infections.
 EUKARYOTIC – true
nucleus
- Evolved from prokaryotes
– specialized membrane-bound organelles,
that perform important cellular functions
- Ex. Protists, Fungi, Plants, Animals
ANIMAL CELL
PLANT CELL