Cells and cell theory Biology For Engineers

Biology For Engineers

1. Cells

2. Definition of Cell A cell is the smallest unit that is capable of performing life functions.

3. What is Cell? The cell is the functional basic unit of life. It was discovered by Robert Hooke and is the functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life.

4. Unicellular and multicellular Organisms, such as most bacteria, are unicellular (consist of a single cell). Other organisms, such as humans, are multicellular. Humans have about 100 trillion cells

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

6. All living things are composed of cells Some organisms are composed of just one cell (like these bacteria you can see on this slide). Other organisms (like plants, animals, and humans) are composed of trillions of cells.

7. Discovery of cell The descriptive term for the smallest living biological structure was coined by Robert Hooke in a book he published in 1665 when he compared the cork cells he saw through his microscope.

8. Types of Cell There are two types of cells: eukaryotic and prokaryotic. Prokaryotic cells are those cells which have nuclear material without nuclear membrane. For ex- bacteria and blue green algae. The cell having well- organized nucleus with a nuclear membrane are called eukaryotic cells.

9. Types of cell white blood cell red blood cell cheek cells sperm nerve cell muscle cell Amoeba Paramecium

10. Shape of cells Generally, cells are round, spherical or elongated some cells are long and pointed at both ends. They exhibit a spindle shape. Cells sometimes are quite long. Some are branched like nerve cells or a neuron. Some are sphere like RBC .

11. CELL THEORY All living things are made up of cells. Cells are the smallest working units of all living things. All cells come from preexisting cells through cell division.

12. THE CELL THEORY The cell is the basic unit of structure. All living things are made up of one or more cells.

13. THE CELL THEORY The cell is the basic unit of function. A cell is the smallest unit that is capable of performing all of the life functions.

14. THE CELL THEORY All cells come from pre-existing cells. Through mitosis, one cell makes two cells, etc.

15. EXCEPTIONS TO THE THEORY Viruses Can only reproduce Mitochondria & Chloroplasts Have their own DNA and can replicate

16. LEVELS OF ORGANIZATION cells Tissue Organs Organ System Organism

17. CELLS & How They Relate To The LIFE FUNCTIONS

18. CELL MEMBRANE REGULATION Allows good stuff and small molecules in, bad stuff and LARGE molecules are “blocked”

19. CELL MEMBRANE EXCRETION all waste products exit through the membrane

20. CELL MEMBRANE TRANSPORT Materials are ABSORBED NUTRITION The ingestion of food

21. CELL MEMBRANE G R O W T H The membrane must increase in size to account for the increase in cytoplasm

22. CHLOROPLASTS SYNTHESIS Site of photosynthesis REPRODUCTION They have their own DNA and can make copies of themselves SYNTHESIS Make proteins at their own ribosomes

23. CYTOPLASM SYNTHESIS Lots of molecules are made here GROWTH An increase in the number of molecules = growth TRANSPORT Diffusion cyclosis

24. MITOCHONDRIA RESPIRATION Site of aerobic respiration REPRODUCTION They have their own DNA and can make copies of themselves SYNTHESIS They make proteins at their own ribosomes

25. NUCLEUS REPRODUCTION Mitosis starts here SYNTHESIS Makes new DNA - chromosomes REGULATION The DNA controls all cell activities

26. RIBOSOME SYNTHESIS Makes proteins GROWTH An increase in the number of molecules leads to growth

27. VACUOLE EXCRETION Stores wastes NUTRITION Stores food

28. PLANT VS. ANIMAL CELLS Plant Cells Onion Cell

29. ANIMAL CELLS