1. Cell Structure & Function

2. Describe this picture. What is the basic substance required to make this structure.?

3. BRICKS ACT AS BUILDING BLOCKS TO CREAT THE BRICK BUILDING.

4. What are we made up of?

6. So what is the definition of a cell??

7. They are building blocks of all living things and they are the basic unit of life !!!!!

8. What do you think the ‘building block of a dog is ?

9. So what are the various points you can think of to describe a cell?

10. Cell Theory All living things are made up of cells.
Cells are the smallest working units of all living things.
They are the structural and functional unit of life. (why?)
All cells come from preexisting cells through cell division.

11. Refined Definition of Cell
A cell is the smallest structural and functional unit of life.

12. Cell Theory All living things are made up of cells.
Cells are the smallest working units of all living things.
They are the structural and functional unit of life. (why?)
All cells come from preexisting cells through cell division.

13. A cell is the smallest structural and functional unit of life.
Definition of Cell
A cell is the smallest structural and functional unit of life.

14. Examples of Cells
Amoeba
Plant Stem
Bacteria
Red Blood Cell
Nerve Cell

15. diameter of DNA double helix
tallest trees
adult human
chicken egg
frog embryo
most eukaryotic cells
mitochondrion
Figure: 04-01
Title:
Relative sizes.
Caption:
Dimensions commonly encountered in biology range from about 100 meters (the height of the tallest redwoods) through a few micrometers (the diameter of most cells) to a few nanometers (the diameter of many large molecules).
most bacteria
virus
proteins
diameter of DNA
double helix
atoms

16. “Typical” Plant Cell

17. “Typical” Animal Cell

18. Cell Parts
Organelles

19. Surrounding the Cell

20. Cell Membrane
It is the Outer membrane of an animal cell. It is located below the cell wall in the plant cell.
Its main function is to control the movement of substances in and out of the cell.
It is a Double layer called lipid bi layer
Scientists say that the cell membrane is selectively permeable, which means that only certain substances can permeate (go through) the membrane.
It is found in both plant and animal cells
It also helps give shape to the cell

21. Cell membrane

22. Cell Wall
Most commonly found in plant cells & bacteria. NOT present in animal cells
Surrounds the cell membrane in a plant cell
Most important function is to give the cells shape and rigidity.
It also Supports & protects cells.

23. Inside the Cell

24. Cytoplasm Jelly-like substance Surrounded by cell membrane
All cell organelles are embedded in this.
It contains the chemicals which are necessary to carry out all the reactions that happen within a cell.
Important chemical reactions occur in the cytoplasm whereby some of the products are utilized by the organelles.

25. Nucleus Easiest organelle to see under the microscope
Control center of the cell
Directs cell activities
Separated from cytoplasm by nuclear membrane
Contains genetic material – DNA
Controls the production of proteins in the cells
All the information regarding the cell and its activities are stored here.

26. Nucleus

27. Chloroplast
Usually found in plant cells. Also present in trace amounts in Bacteria, fungi and algae.
It is not present in animal cells.
Surrounded by two membranes (inner and outer)
Contains a green pigment called chlorophyll which traps light energy and converts it into food through photosynthesis.
It contains its own DNA.

28. Chloroplast

29. Mitochondria
Produces energy through chemical reactions – breaking down food.
Surrounded by two membranes (outer and inner membrane). The inner membrane is folded several times.
Controls level of water and other materials in cell
Recycles and decomposes proteins, fats, and carbohydrates
Contain their own DNA.

31. Vacuoles Membrane-bound sacs for storage, digestion, and waste removal
 Vacuoles may contain large food particles, enzymes, water, or many other substances. 
Usually one large vacuole is present in plant cell (takes up 95% of space)
Animal cells have small vacuoles but they are more in number.

33. Ribosomes Each cell contains thousands of ribosomes.
Produced in the nucleus of a cell
They act as factories of the cell to produce Proteins.
They can be found either in their free form in the cytoplasm or attached to an organelle (The rough Endoplasmic Reticulum.)
It is made up of a large sub unit and a small sub unit.

35. Lysosome Digestive organelle.
They contain acid enzymes to break down food particles,waste materials and cellular debris. It can also destroy organelles that have been damaged. If the celllacks an adequate amount of food, the lysosomes may actually digest healthy organelles to provide the cell with energy.
Found only animal cells
Should the lysosome break and release its powerfulenzymes, the entire cell can be destroyed, which is why the lysosome is sometimes called the "suicide sac."

37. Endoplasmic Reticulum
Two types – Smooth and rough ER
Rough ER – as they have ribosomes attached to their surface. Protein synthesis occurs here.
Smooth ER – Carbohydrate metabolism and lipid and steroid synthesis. No ribosome present.
Extends from the Nucleus