Presentation is loading. Please wait.

Presentation is loading. Please wait.

Pg. 68. Observed the first cells; dead plant cells (cork) Coined the term “cell”

Similar presentations


Presentation on theme: "Pg. 68. Observed the first cells; dead plant cells (cork) Coined the term “cell”"— Presentation transcript:

1 Pg. 68

2 Observed the first cells; dead plant cells (cork) Coined the term “cell”

3 First person to observe living cells Ground microscope lenses with precision Called the organisms, animalcules (We call them protists.)

4

5 Cell-the basic unit of life

6 1) All living organisms are composed of one or more cells. 2) Cells are the basic unit of structure and function in an organism. 3) Cells come only from other cells.

7 M. Schleiden- “All plants are composed of cells” T. Schwann-”All animals are composed of cells.”

8 Cell division

9 There is a large variety of cells: Skin cells Nerve cell Bacterial cell Onion cells

10 There are 1000 micrometers in one millimeter!! WHY ???

11 As a cell grows its volume increases much faster than its surface area. If the cell’s volume were too large, it’s surface area would not be able to meet the cell’s needs.

12 How would you answer this? As a cell becomes smaller, its surface area-to- volume ratio ___________________. A. increases B. decreases C. stays the same D. becomes less important

13 “Form follows function” - the shape of a cell is often related to its function The long extensions of a nerve cell are specialized for sending and receiving impulses

14 Most cells are between 10-50 micrometers The smaller the cell the more efficient it is at moving materials across its membrane How many cells would fit on the head of a pin that is 2mm in diameter???

15 Prokaryotes… Eukaryotes… …include bacteria …include plant and animal cells

16 PROKARYOTES 1) no nucleus 2) no membrane-bound organelles 3) smaller 4) no mitochondria EUKARYOTES 1) have a nucleus 2) membrane-bound organelles 3) larger 4) have mitochondria

17 A collection of identical cells living in a colony, NOT a multicellular organism Volvox

18 Regulates movement of substances into and out of cells; outer boundary of the cell Composed of proteins, carbohydrates, and lipids * All important in the functioning of the membrane

19 1 ) They serve as attachment sites for molecules in the extracellular fluid 2) Transport materials across the cell membrane

20 Helps cells recognize each other

21 1) forms vesicles with cell membrane 2) provides a boundary between cell and surroundings 3) transports substances into and out of the cell

22 S.A. = 4πr 2 2µm cell = 12. 56 20 µm cell= 1256 Increased by 100 times

23

24 -controls cell functions -houses (holds) DNA/ chromosomes Contains: 1) Nuclear Envelope- contains pores that serve as passageways for RNA to enter and leave 2) Nucleolus- the site where ribosomes are made


Download ppt "Pg. 68. Observed the first cells; dead plant cells (cork) Coined the term “cell”"

Similar presentations


Ads by Google