do now … what characteristics are common to all living things? what are cells? name different...
TRANSCRIPT
DO NOW … What characteristics are common to all
living things?
What are cells?
Name different types of cells you know of...
What is a difference between living and non-living things?
THE CELLChapter 1
DO NOW … What are the two main types of
cells?
Do all cells have the same structure?
Look at the cells to the right. What are some similarities? Differences?
Objectives
Describe how cells were discovered and named.
Identify the scientists that discovered and observed cells.
List the 3 parts of the cell theory.
What is a cell?
Basic structural and functional unit of all living organisms!
They come in different shapes + sizes
Unicellular vs. Multicellular
Unicellular – a single cell
Multicellular – made up of many cells
Who discovered the cell?
ROBERT HOOKE
Observed dead cork cells
Said boxes looked like tiny rooms or jail “cells”.
Used a microscope at 30x magnification
How were cells discovered?
The light microscope
helped discover cells!
Cork cells!
*Cork is from tree bark (dead cells)
Animalcules
Who else discovered the cell?
ANTON VAN LEEUWENHOEK
Observed pond water
1st to observe “living” cells
Used a microscope at 300x magnification
Do you have these recipes at home?
People thought organisms grew from non-living materials!
Fransisco Redi Experiment
Placed meat in both an open container and a closed container to see what happened.
Redi’s Conclusion
Maggots come from flies, NOT the meat!
Life must come from life, which proved that spontaneous generation is not real!
People still did not believe him but he was right.
Louis Pasteur Experiment
Showed that bacteria are present in air and do not appear spontaneously.
Louis Pasteur Conclusions
Discovered that cells MUST come from other cells
Disproved “Spontaneous Generation” and said life cannot just appear out of no where.
Helped verify Redi’s research!
Pasteurization
Pasteur came up with the idea of Pasteurization after discovering bacteria could contaminate milk from the air.
This process kills the bacteria so that it does not harm us!
Used in milk, cheese, yogurt, etc.
http://bcs.whfreeman.com/thelifewire/content/chp03/0302003.html
Cell Theory = Every living thing is made of one or
more cells Cells carry out the functions needed
to support life Cells come only from other living
cells
Do Now
Please complete the worksheet in front of you!!
Objectives
Compare and contrast a scanning electron microscope vs. a transmission electron microscope.
Describe prokaryotic and eukaryotic cells.
Bill Nye!!
http://www.youtube.com/watch?v=RU5Ymc00S4w
Section 1.2 - Microscopes
How small are cells? Unit used =
micrometer (um)One millionth of a
meter
Most cells range from 1 um to 1000
um.
Types of Microscopes
1. Light Microscope
2. SEM Microscope
3. TEM Microscope
Light Microscope
Uses light
Looks at thin specimen
Total Magnification = 40x-1000x
Use to see cells, but not detailed organelles
SEM vs. TEM
SEM1. “Scanning electron microscope”
2. Beams of electrons bounce off the surface of the coated cell.
3. Images appear 3D- Outside Specimen
4. Total Magnification = 100,000x
5. Must be dead . Specimen coated in metal
TEM1. “Transmission electron
microscope”
2. Electrons pass through the think section.
3. Images appear 2D
4. Total Magnification = 300,000x
5. Allows us to see organelles inside the cell
Do Now!!
What are the three types of microscopes?
What is found INSIDE a cell?
Do plant cells and animal cells have the same stuff inside?
Objectives
To compare and contrast animal vs. plant cells.
Identify each organelle in a diagram of a cell.
Explain the function of each organelle
To create flash cards for the next test
SEM
TEM
Prokaryotic vs. Eukaryotic cells
What are the differences you can see?
Prokaryotic Cells
Have circular DNA
NO nucleus
Does not have membrane bound organelles
Most unicellular organisms are prokaryotes
Example: Bacteria
Eukaryotic Cells
Have linear DNA – double helix shape
Has nucleus
Have membrane bound organelles
All multicellular organisms are eukaryotic cells. Some are unicellular though.
Example: You!
Cell Organelles
1. Plasma membrane
2. Cytoplasm/cytoskeleton
3. Nucleus
4. Ribosomes
5. Endoplasmic Reticulum
6. Golgi Apparatus
7. Lysosomes
8. Centrioles
9. Cilia and Flagella
10. Mitochondria
11. Central Vacuole
12. Chloroplasts
13. Cell Wall
Each organelle has its own purpose and function!!
THE OUTSIDE – protects the internal structures of the cell.
Selective permeability -Determines what comes in and out of the cell
A.K.A- Cell Membrane!
Found in: Animal and Plant cells
Plasma Membrane
Cytoplasm/Cytoskeleton
Cytoplasm- Clear FLUID that contains the organelles.
Cytoskeleton- Provides the FRAMEWORK for the cell, holds organelles in place.
Found in: Plant and Animal cells
NucleusNucleus- CONTROLS the cell
Nucleolus- produces ribosomes
Nuclear Pores- Allows things in and out of the nucleus.
Nuclear Envelope- Membrane surrounding nucleus
Found in: Plant and Animal
Challenge Question
Where do you find the DNA in a eukaryotic cell?
If prokaryotes do not have a nucleus, where is their DNA?
Ribosomes
Produces Proteins!
Proteins are made up of one or more polypeptide chains of amino acids.
Found in: Plant and Animal
Endoplasmic Reticulum
Rough- Contains ribosomes and synthesizes PROTEINS
Smooth- No Ribosomes, synthesizes LIPIDS (fats)Found in: Plant and Animal
Index Cards!
Front:
Name of Organelle
Drawing
Back:
Location
Function
Do Now!!
Please finish making your 5 notecards from last class!
Objectives
To compare and contrast animal vs. plant cells.
Identify each organelle in a diagram of a cell.
Explain the function of each organelle
To create flash cards for the next test
To observe different kinds of cells under a microscope
Golgi Apparatus
Modifies proteins and fats and gets them ready for export!(proteins are eventually released to outside of cell)
Found in: Animal and Plant
Lysosomes
Contains ENZYMES that break down cellular waste product and debris
Found in: Animal (rare in plant)
*The clean-up crew!
Centrioles
Organelles made of microtubules involved in cell division (located in cytoplasm)! (will talk about this later when we do mitosis!)
Found in: Animal
Cilia and Flagella
Flagella- Used in cells for movement (longer & less numerous than cilia).
Cilia- Used in stationary cells for moving substances around the outside of the cell (look like hairs).
Found in: Animal and Prokaryote
Mitochondria
Convert oxygen into ENERGY (ATP)
(we will talk about this more when we do cellular respiration!!)
Found in: Animal and Plant
*Powerhouse of the cell!!
Index Cards!
Front:
Name of Organelle
Drawing
Back:
Location
Function
Do Now!!
• Which is a plant cell? Animal cell? How do you know?• What is the role of the mitochondria?
Objectives
To compare and contrast animal vs. plant cells.
Identify each organelle in a diagram of a cell.
Explain the function of each organelle
To create flash cards for the next test
To label animal and plant cells
Central Vacuole
LARGE WATER “bubble” in the plant cell
Maintains the SHAPE of the cell, without it, the plant cell would shrink and the plant would wilt
Stores water, along with ions, nutrients, and waste.
Found in: Plant
Chloroplasts
Captures LIGHT ENERGY and converts it to chemical energy (sugar)
Found in: Plant
Cell Wall
Supports the plant cell and maintains its shape
Works with central vacuole to maintain “Turgor Pressure”
Found in: Plant
Index Cards!
Front:
Name of Organelle
Drawing
Back:
Location
Function
Challenge Question!
How can the chloroplast, a structure found in plant cells but not in animal cells, provide energy for both plants and animals?
Do Now!!
Please create a Venn diagram:
Plant Animal
Objectives
Identify each organelle in a diagram of a cell.
To label animal and plant cells.
To complete reading activity summing up organelles and their functions.
Endosymbiotic Theory
Explains the origin of chloroplasts and mitochondria and their complex, double membranes.
Theory: Chloroplasts and Mitochondria were once prokaryotes that were engulfed!!
Theory = Evidence!!
•Have circular DNA like bacteria•Replicates(reproduces) like bacteria separate from the host cell•Make their own proteins•Two membranes (one from the host cell and one from their own cell membrane)
Specialization
•Specific cells perform specific functions.
Ex: Blood cells can only be blood cells. Muscle cells cannot be turned into blood cells.
Organization
Organisms are organized:
Cells Tissue Organ Organ System Organism
Organization: plants too!
Cell Tissue Organ (leaf) Organ system (leaves, stems, roots) Organism