1. Cells and Cell Structures

2. Cells All living things are made of cells
Cells are the basic structural and functional unit of living things
New cells are produced from existing cells
All cells (prokaryotic and eukaryotic) outer have membranes

3. Cells Cytoplasm – a thick liquid medium enclosed in the membrane
In eukaryotes – “all material” inside the cell and outside the nucleus
Mainly composed of water (~80% water), salts and proteins
Role – internal substructure, some cell signaling

4. Cell Membrane
Cell membrane – lipid bilayer – stops most things moving in and out

5. Phospholipid Bilayer

6. Organelles
Function and Location, what do they do and how do they do it:
Specialized structure within a eukaryotic cell that performs a specific function
Have their own membranes
Those with membranes are ONLY in eukaryotic cells

7. Organelles
NUCLEUS
Contains MOST of cells DNA (genetic information); coded instructions for making protein
Because DNA codes for proteins (enzymes, structures, etc), it ‘controls’ the cell
Most of the time DNA is ‘visible’ as chromatin (unwound chromosomes)
Nucleolus – dense region where ribosome assembly begins (they’re made of RNA)
Pores in the nuclear membrane – some molecules in and out of the nucleus (RNA, small proteins, etc.)

8. Organelles
NUCLEUS

9. Organelles
NUCLEUS
Prokaryotes have DNA too, it’s just not in a nucleus

10. Organelles RIBOSOMES (no membrane)
Proteins are ‘translated’ at the ribosome
RNA comes from the nucleus
Amino acids are brought to the ribosome
RNA (copied from DNA) ‘codes’ for amino acids -> proteins
So, essential for protein synthesis and no membrane…
Also found in prokaryotes
NO MEMBRANE!!!!!

11. Organelles
RIBOSOMES

12. Organelles
RIBOSOMES

13. Organelles
RIBOSOMES

14. Organelles ENDOPLASMIC RETICULUM (ER) Internal membrane system
Synthesis site of many different molecules
Two types
Smooth ER
Rough ER

15. Organelles SMOOTH ER Fat/lipid synthesis (cell membrane parts)
Steroid synthesis
Carbohydrate metabolism
Detoxification

16. Organelles ROUGH ER Has ribosomes on it – giving it a ‘rough’ look
Protein synthesis – mostly for proteins leaving the cell
Enzymes for lysosomes
Membrane proteins

18. Organelles Golgi Apparatus (or Body)
Stacked membranes in the cytoplasm
Packages proteins (from rough ER) to be released outside the cell

19. Organelles
Golgi Apparatus

20. Organelles Golgi Apparatus (or Body)
Stacked membranes in the cytoplasm
Packages proteins (from rough ER) to be released outside the cell
Why put membrane around them to transport?
Packages other molecules for transport as well

21. Organelles Mitochondrion (singular)
Uses energy (electrons and protons!) from molecules to make an ‘energetic molecule’ for your cells = ATP
CONVERTS energy into form usable by cell
Has TWO membranes – inner and outer

22. Organelles
Mitochondrion

23. Organelles Mitochondrion (singular)
Inherited from your mother (from the egg)
Mitochondria from sperm cell are left behind with the flagellum at fertilization
They have their OWN DNA!!!!
We’ll spend a lot more time on these in the future

24. Organelles Chloroplast
Capture energy from sunlight and use it to make sugars
Uses solar energy to take electrons and protons from water!!!
Energy from these electrons and protons are then used to ‘make’ the sugars
Chlorophyll inside ‘captures’ solar energy
Two membranes again

25. Organelles
Chloroplast

26. Organelles Chloroplast And their OWN DNA!!!!
Yes, we’ll be spending a lot more time on them in the future

27. Homework
Venn Diagram – mitochondrion and chloroplast