1. Biology 112 – Chapter 7 CELLS
Section 7-1 and 7-2 of textbook objectives:
List scientists who contributed to the cell theory
List the components of the cell theory
Compare prokaryote and eukaryote cells
Label a plant and an animal cell
Know the functions of cell organelles

2. Early Contributions
Robert Hooke - First person to see cells, he was looking at cork and noted that he saw "a great many boxes. (1665)
Anton van Leeuwenhoek - Observed living cells in pond water (1673)

3. Leeuwenhoek saw these things in pond water. What did he call them?

4. Theodore Schwann - zoologist who observed tissues of animals had cells (1839)
Mattias Schleiden - botanist, observed tissues of plants contained cells ( 1845)
Rudolf Virchow - also reported that every living thing is made of up vital units, known as cells. He predicted that cells come from other cells. (1850 )

5. The Cell Theory
Every living organism is made of one or more cells. (Schwann/Scheilden)
2. The cell is the basic unit of structure and function. (Hooke)
3. All cells arise from pre- existing cells. (Virchow)
*Why is the Cell Theory called a Theory and not a Fact?

6. Cell Features ALL cell have these parts
Ribosomes – make protein for use by the organism
Cytoplasm – fluid material within  cell
DNA – genetic material
Cytoskeleton – internal framework of cell
Cell Membrane – outer boundary, some things can cross the cell membrane

7. Comprehension Checkpoint
Answer true or false
Robert Hooke was the first person to see cells.
Bacteria cells have a cell membrane.
The Cell Theory was developed by a single scientist.
Plant cells have cytoplasm.
Cells taken from fungi do not have DNA.
Cells can only come from pre-existing cells.
It only took five years to develop the Cell Theory.

8. Prokaryote Cells The first cells to inhabit the earth Simple cells
Bacteria Conjugation
These cells do NOT have a nucleus, their DNA is circular and floats in the cytoplasm
Some bacteria have a tail-like structure called a flagella, that helps it to move.
A capsule surrounds some bacteria and helps them avoid the body’s immune system

9. Bacteria Images
Bacteria that causes Anthrax

10. Benefits of Plasmids

11. Bacteria belong to a group of cells that do not have a ____________
CHECKPOINT
LABEL THE BACTERIA H
Bacteria belong to a group of cells that do not have a ____________

12. Eukaryotic Cells Cells found in plants, animals, protists, and fungi
The cell is composed of 4 main parts:
Cell membrane
Cytoplasm
Nucleus – “control center” of cell, DNA
Organelles – small structures that carry out specific functions (“little organs”)

13. Compare Prokaryote to Eukaryote

14. Nucleus Usually found at center of cell
Has a nuclear membrane & nuclear pores
 Contains cell’s DNA in one of 2 forms
chromatin - DNA and proteins, becomes...
chromosomes - during cell division
Nucleolus (little nucleus)
which makes the cell’s ribosomes
is not an organelle
Not enclosed

16. True of False
1. All cells have a nucleus.
2. All cells have a cell membrane.
3. Eukaryote cells are the only cells to have a flagellum.
4. The nucleus contains the cell’s DNA.
5. Chromatin will become chromosomes.
6. The nucleolus makes the cell’s DNA.

17. Cell Organelles
Mitochondria – cell’s energy center; turns food into a chemical energy called ATP
The mitochondria is sometimes called the “powerhouse” of the cell
Some muscle cells have 20,000 mitochondria.
Cells near the skin have many less (few hundred).
The number varies by tissue and organism

18. Mitochondria

19. Cell Organelles
Golgi Apparatus – processes, packages and secretes proteins. It is comparable to a factory or a post office. Transforms proteins into more complex molecules
*A vesicle forms with Golgi to transport substances outside cell.  

20. GOLGI BODIES (GAWL jee)

21. MITOCHONDRIA
Quick fact:
In humans, Mitochondrial DNA is inherited from the mother only
Mitochondrial DNA from the male is destroyed at fertilization
In animals, mtDNA inheritance varies

22. Cell Organelles
Lysosome – Contains digestive enzymes, breaks things down, "suicide sac”, built in the golgi bodies
Endoplasmic Reticulum – Transport, "intracellular highway".
-Rough ER contains many ribosomes & is involved in protein synthesis
 -Smooth ER no ribosomes

23. Rough Endoplasmic Reticulum
Involved with the production and processing of proteins
In cells that produce an abundance of proteins, there are many rough ER
It is connected to the nuclear envelope
Result: the nucleus has direct access to proteins and other materials
There are two basic kinds of endoplasmic reticulum morphologies: rough and smooth. The surface of rough endoplasmic reticulum is covered with ribosomes, giving it a bumpy appearance when viewed through the microscope. This type of endoplasmic reticulum is involved mainly with the production and processing of proteins that will be exported, or secreted, from the cell. The ribosomes assemble amino acids into protein units, which are transported into the rough endoplasmic reticulum for further processing. These proteins may be either transmembrane proteins, which become embedded in the membrane of the endoplasmic reticulum, or water-soluble proteins, which are able to pass completely through the membrane into the lumen. Those that reach the inside of the endoplasmic reticulum are folded into the correct three-dimensional conformation, as a flattened cardboard box might be opened up and folded into its proper shape in order to become a useful container. Chemicals, such as carbohydrates or sugars, are added, then the endoplasmic reticulum either transports the completed proteins to areas of the cell where they are needed, or they are sent to the Golgi apparatus for further processing and modification.

24. RIBOSOMES Synthesize (make) proteins
Float freely or attached to the endoplasmic reticulum (ER)
Ribosomes are made in the nucleolus

25. Cytoskeleton – Helps cell maintain support & shape; movement
a. microtubules- hollow tubes made of tubulin
b.  microfilaments-threadlike made of actin
Centrioles- only in animal cells; used during cell division (paired) 

27. Vacuole – storage area for water and other substaces, plant cells usually have a large central vacuole

28. Protein Production
The cell is like a factory. Its product is protein which goes to body to serve different functions.
DNA has instructions to build protein
Instructions are sent to ribosomes
The ribosomes build protein and sends it through ER
The proteins go to golgi bodies where they are packaged for export

29. THE ANIMAL CELL

30. Cheek Cells Seen Through Microscope

31. NAME THE PARTS

32. Plant Cells
CELL WALL – provides additional support / protects the cell/ gives it shape / made of cellulose
CHLOROPLASTS – contain green pigment, photosynthesis
Chrolophyll - A green pigment that gives leaves & stems their color
CENTRAL VACUOLE – large water container

33. PLANT CELL
Can you identify the parts?

34. Anacharis Cells Viewed With a Microscope

35. Animal Cell vs Plant Cell

36. Organelles With DNA
Mitochondria and chloroplasts have their own DNA (separate from the nucleus)
This supports the ENDOSYMBIOSIS THEORY which states that eukaryotic cells evolved when prokaryote cells engulfed or absorbed other cells.

37. CELL MEMBRANE
Selectively permeable ; it regulates what comes into the cell and what leaves the cell
It is composed of a double layer of phospholipids with proteins embedded throughout

38. Group of cells working together
FROM CELL TO ORGANISM
Cell
The basic unit of life
Tissue
Group of cells working together
Organ
Group of tissues working together
Organ System
Group of organs working together
Organism
Any living thing made of 1 or more cells

39. Inner Life of a Cell