1

The Cell

The building blocks of life

2

The Cell

Go to the Cell Size link. http://www.cellsalive.com/howbig.htm

3

The Cell

Cells are not the smallest structure that make up living organisms. They are merely the smallest functional units. Cells themselves contain smaller units called organelles. Organelles are tiny cell structures that carry out specific functions with a cell. Produce energy, build and transport

materials, and store and recycle waste.

4

The Cell

To get inside…… You must first go through the Cell Wall. The

Cell Wall is a rigid layer of non-living material that surrounds mostly plant cells Animal cells do not have cell walls. Made of Cellulose Protects and supports a plant cell. It’s what gives a tree its strength. Figure 1 on your plant cell diagram the thick part

5

The Cell

All cells have a Cell Membrane. In plants it is next to the cell wall. The Cell Membrane separates the cell from

its environment. The Cell Membrane controls what

substances come into and out of a cell. Figure 1 on your plant and animal cell diagram Thin layer on

the plant cell diagram

6

The Cell

After you go through the cell membrane, you enter the Cytoplasm. Cytoplasm is a clear gel-like fluid that fills the cell and contains the organelles. Constantly moving fluid

7

The Cell

Floating around within the cytoplasm we have all kinds of good stuff:

The Golgi Bodies The packaging and shipping department

for newly formed proteins in the cell. A folded collection of sacks and tubes. Figure 3 on your plant and animal cell diagram

8

The Cell

More floating stuff: Endoplasmic Reticulum (E.R.)

Network of tubes or membranes Carries materials through cell Figure 2 on your plant and animal cell diagram

9

The Cell

More floating stuff: Ribosomes

Small bodies free or attached to E.R. Produces proteins

10

The Cell

More floating stuff: Mitochondrion.

Bean-shaped with inner membranes. Breaks down sugar molecules into energy. Figure 6 on your plant and animal cell diagram

11

The Cell

More floating stuff: Vacuole

Small fluid-filled sacs Store food, water, waste. Figure 5 on your plant cell diagram

12

The Cell

More floating stuff: Lysosome

Small, round, with a membrane Breaks down larger food molecules into

smaller molecules. Digests old cell parts. Figure 5 on your animal cell diagram

13

The Cell

More floating stuff: Chloroplast

Plants only, not animal cells. Green, oval usually containing chlorophyll

(green pigment). Uses energy from sun to make food for the

plant (photosynthesis) Figure 7 on your plant cell diagram

14

The Cell

Finally.. The brains of the operation. The Nucleus

The brain of the cell, directing all the cells activities.

Surrounded by the Nuclear Membrane Protection and regulation of material transport.

Figure 4 on your plant and animal cell diagram

15

The Cell

And in that cell brain…... The Chromatin

Genetic material which chemically directs all of the cell’s activities.

Made of DNA and affiliated proteins Fine twisted stuff within Figure 4 on your plant and animal

cell diagram

16

The Cell

And in that cell brain…... The Nucleolus

Instructions in DNA are copied here Works with ribosomes in the synthesis of

protein Dark area within Figure 4 on your plant and animal cell

diagram

17

A few words about a few other cells..

18

Bacteria

This little guys are about 10x smaller than the average animal cell.

They have cell walls and cell membranes…

They do not have a nucleus!

19

Important definition here! Organisms whose cells contain a

nucleus are called……Eukaryotes Organisms whose cells DO NOT

contain a nucleus are called……Prokaryotes

Bacteria are prokaryotes.

20

Important exception!

Red blood cells in mammals (like you and me) DO NOT contain a nucleus or even DNA.

21

Bacteria

Come in three basic shapes. Sphere : cocci Rod : bacilli Spiral

22

Bacteria : cocci

Diplococcus

http://student.ccbcmd.edu/courses/bio141/lecguide/unit1/shape/diplo.html

23

Bacteria : cocci

Streptococcus

http://student.ccbcmd.edu/courses/bio141/lecguide/unit1/shape/gpstrep.html

24

Bacteria : bacilli

Streptococcus

http://www.bioweb.uncc.edu/1110Lab/notes/notes1/labpics/lab1pics.htm

25

Bacteria : Spiral

http://www.uic.edu/classes/bios/bios100/labs/celllab.htm

26

Bacteria

We are not going to get back into cell structure, however, it is at least worth looking at bacteria mobility.

Flagellum long whip like structure spins like a propeller Rotary joint

27

Bacteria

http://images.encarta.msn.com/xrefmedia/aencmed/targets/illus/ilt/T028556A.gif

28

Bacteria

http://www.answersingenesis.org/docs/images/flagellum.jpg

29

Bacteria

Bacteria exist in two Kingdoms. Archaebacteria

Live in extreme environments Acids, intestines, sewage, 110 degree water etc Produce foul odors

Eubacteria Live everywhere else Many are beneficial

30

Bacteria Reproduction

Asexual reproduction Reproduction with only one parent binary fission

one cell divides to form two identical cells

Sexual Reproduction Two parents combine genetic material Conjugation

Transfer genetic material through a thin bridge

31

Bacteria Conjugation

http://kentsimmons.uwinnipeg.ca/16cm05/1116/27-x1-ProkaryoteConjugation.jpg

32

Bacteria binary fission

http://www.emc.maricopa.edu/faculty/farabee/BIOBK/69091a.jpg

33

A tiny glimpse at the Virus

Simple success

34

Virus

http://webs.wichita.edu/mschneegurt/biol103/lecture17/Ebola_EM.jpg

35

Virus

Non-living Do not use energy to grow Do not respond to their surroundings Sub-microscopic Unable to grow or reproduce outside a host

cell. A host is an organism that harbors a virus or

parasite.

36

Virus

Each viral particle, or virion, consists of just two parts Genetic material, DNA or RNA. A protective protein coat called a capsid.

37

Virus

Viruses multiply by entering a host cell and taking over cell function with its own genetic material.

The infected host cells then produce more protein and genetic material to assemble new virion.

38

Virus

http://www.ifpma.org/Influenza/index.aspx?001_The_Influenza_Virus/001a_Influenza_Virus.html

39

Virus

http://www.weblo.com/domain/available/grupvirus.com/

40

High Resolution photomicrograph of the SimianVirus

http://www.nimr.mrc.ac.uk/monkey_molecules/other_structures/