1. The Cell A cell is the smallest unit of living matter.
Don’t confuse this with: atom, element, proton, etc.

2. Cell Size

3. Three Main Parts
Plasma membrane
Nucleus
Cytoplasm

4. These are ALL CELLS!

7. Cell Theory “Theory” is not a casual term in science.
Tested innumerable times with consistent results.
Universally accepted
One of the most basic, fundamental concepts in the foundation of biology.

8. Cell Theory
1800s; several scientists working independently had similar results.
1. All organisms are made of cells.
2. A cell is the structural & function unit of organs.
3. All cells come from pre-existing cells.
4. Cells are capable of self-reproduction.

9. There are two types of cells:
Prokaryotic- cells that DO NOT have a nucleus or other cell ORGANELLES
Eukaryotic- cells with a NUCLEUS & cell ORGANELLES
Which is more complicated?
REMEMBER YOU ARE EUKARYOTIC!

11. Prokaryotic vs Eukaryotic
Pro = before
Karyote=kernel(nucleus)
DNA is NOT contained within a nucleus
Most have a cell wall outside the plasma membrane
May have type of flagella or pilus
Archaea and Bacteria
Eu= true
Karyote=nucleus
DNA contained in double membraned nucleus
Only plant cells have cell wall
Contains membrane bound organelles
Plants, animals, protists,
fungi

12. Types of Organisms Unicellular organisms Multicellular organisms
Bacteria, Protists, etc.
Multicellular organisms
Plants
Animals
Muscles, skin, nerves, liver, digestive, bones, blood, immune system, lungs, etc.

14. Why cells aren’t bigger
If cells get too large in volume compared to their surface area then it’s difficult to distribute nutrients throughout the cell and too hard to get rid of build up of wastes.

15. A phospholipid bilayer With proteins embedded in it
The Cell Membrane
A phospholipid bilayer
With proteins embedded in it

16. Hydrophillic heads and Hydrophobic tails
The phospholipid consists of hydrophilic heads, which point towards the outside environment and the cytoplasm. The hydrophobic tails repel the water and point in. Thus, the phospholipids form a bilayer that acts like a barrier between the cell and the environment. The phospholipid bilayer also contains cholesterol, which makes the bilayer stronger, more flexible and more permeable. There are a number of important proteins in the plasma membrane

18. Fluid Mosaic Model of the Cell Membrane
The purpose of the membrane is to control what goes in and out of the cell.
Semi-permeable means certain molecules can be transported across the membrane while others are kept out.
Proteins that are found in the bilayer are receptor proteins, which deal with communication, recognition proteins and transport proteins that regulate the movement of water and soluble molecules through the membrane.

20. Transport of molecules across the membrane
Transport is either active or passive.
Active transport is moving molecules against the concentration gradient and energy is required in the form of ATP.
Passive transport is moving molecules down the concentration gradient and no energy is required.
diffusion, which moves from high concentration to low concentration
osmosis, which is the diffusion of water molecules

21. Cell membrane interactive
file:///C:/Documents%20and%20Settings/nancy/My%20Documents/tdc02_int_membraneweb/tdc02_int_membraneweb.htmlfile:///C:/Documents%20and%20Settings/nancy/My%20Documents/tdc02_int_membraneweb/tdc02_int_membraneweb.html

22. The Organelles
..\Desktop\tdc02_vid_organelles.zip

23. The Nucleus- DNA container

24. Nucleus cellular control center
Controls cellular activity
contains hereditary material (DNA in chromosomes)
self duplicating structure -divides when the cell divides

26. Structure of Nucleus Nuclear Envelope (membrane):
Double lipid bilayer: keeps DNA separated from the rest of the cell
Continuous with Endoplasmic Reticulum
Nucleolus: assembly of ribosomes for protein synthesis
Nuclear pores: holes that allow stuff in and out

28. Endoplasmic Reticulum

29. Rough Endoplasmic Reticulum
“HIGHWAY” for cell transport
consists of a network of interconnected, flattened sacs whose walls are formed of a single membrane. The outer surface is "rough" because it is studded with small particles called ribosomes.
The ribosomes synthesize proteins and discharge them into the sacs where they are packaged in membranes which travel through the cytoplasm to other organelles…….
(GOLGI BODIES) where they are further processed.

32. Golgi Bodies Add carbohydrates component to
    the protein and package the 
    finished product before it leaves 
    the cell.
  Form the plasma membrane and
    membranes of lysosomes

34. Lysomes produced by the Golgi apparatus
contain powerful protein digesting enzymes
responsible for the breakdown and absorption of materials taken in by the cell.
Often, a cell engulfs a foreign substance through ENDOCYTOSIS, another form of active transport. During endocytosis, the cell membrane puckers up, forms a pouch around materials outside the cell, and pinches off to become a vesicle. If the contents need to be destroyed, lysosomes combine with the vesicle and release their enzymes.

36. vacuoles
fluid-filled, membrane-surrounded cavities inside a cell. The vacuole fills with food being digested and waste material that is on its way out of the cell.
removing unwanted structural debris surrounding the cell
sequestering materials that might be toxic to the cell
containment of waste products
maintaining internal hydrostatic pressure or turgor within the cell (especially plant cells)
storing small molecules
exporting unwanted substances from the cell.

37. vacuoles

38. Mitochondria Mitochondria are the cells' power sources.
They are distinct organelles with two membranes.
Usually they are rod-shaped, however they can be round.
The outer membrane limits the organelle.
The inner membrane is thrown into folds or shelves that project inward. These are called "cristae mitochondriales
Contain their own DNA which can be passed on

42. Endosymbiosis
It is theorized that mitochondria and chloroplasts were once free living bacteria that got caught in evolution
Both are double membraned, contain their own DNA and can self replicate

43. Quick check
What is meant by the phrase "the cell is the functional unit of life"?
How are the organelles in a cell like the organs in a human body?
Why do you think cells that produce large numbers of proteins have more rough endoplasmic reticulum (ER) than cells that produce fewer proteins?
In which kinds of human cells would you expect to find the most mitochondria? The most lysosomes? The most ribosomes? Explain your answers.

44. centrioles

45. Centrioles
Found only in animal cells, these paired organelles are typically located together near the nucleus,
centrioles are positioned so that they are at right angles to each other, Each centriole is made of nine bundles of microtubules (three per bundle) arranged in a ring.
Centrioles play a notable role in cell division.

46. cytoskeleton
ELEMENTS OF THE CYTOSKELETON All of the microfilaments and microtubules combine to form the cytoskeleton of the cell.
The cytoskeleton is different from cytoplasm. The cytoskeleton provides structure. Cytoplasm is just a fluid.
The cytoskeleton connects to every organelle and every part of the membrane. Think about an amoeba. All of the pieces work together so that the foot might reach out towards the food. Then the lysosomes and peroxisomes are sent to begin digestion. The movement of the organelles and cytoplasm is all related to the tubules.

47. Plant Cell

48. Plant cell wall rigidity of the cell wall renders plants sedentary
Made of Cellulose
animals lack of wall allows their cells more flexibility, which is necessary for locomotion.
protects the intracellular contents
provides a porous medium for the circulation and distribution of water, minerals, and other nutrients, and
houses specialized molecules that regulate growth and protect the plant from disease.

49. Cell wall
The main chemical components of the primary plant cell wall include cellulose (in the form of organized microfibrils; a complex carbohydrate made up of several thousand glucose molecules linked end to end.

50. Plant cell wall

51. Chloroplasts
Chloroplasts are specialized organelles found in all higher plant cells. These organelles contain the plant cell's chlorophyll, hence provide the green color. They have a double outer membrane. Within the stroma are other membrane structures - the thylakoids and grana (singular = granum) where photosynthesis takes place.

52. Chloroplasts

53. DIFFERENCES BTW PLANT AND ANIMAL CELLS
PLANT CELL
Fixed structure.
Has a cellulose cell wall and a cell membrane
Chlorophyll in chloroplasts
large vacuoles
ANIMAL CELL
Can change shape.
No Cellulose cell wall
No Chlorophyll or chloroplasts
Small or no vacuoles
Has centrioles