1. AP BIOLOGY Chapter 6 Cell Structure & Function WHAT’S NEW you didn’t learn in BIO I?
Slide shows combined and modified from:

3. DOUBLE MEMBRANE is fused in spots forming NUCLEAR PORES
NUCLEAR ENVELOPE
DOUBLE MEMBRANE is fused in spots forming NUCLEAR PORES
NUCLEAR LAMINA- netlike array of protein filaments on nuclear side of envelope that maintains the shape of the nucleus
(Play a role in reforming nuclear membrane after cell division, if you inject antibodies to lamina proteins, nucleus can’t reform after mitosis)

4. NUCLEAR ENVELOPE Figure 6.10 Nucleus 1 µm Nucleolus Chromatin
Inner membrane
Outer membrane
Nuclear pore
Rough ER
Pore
complex
Surface of nuclear envelope.
Pore complexes (TEM).
Nuclear lamina (TEM).
Close-up of nuclear
envelope
Ribosome
1 µm
0.25 µm
Figure 6.10

8. ENDOMEMBRANE SYSTEM
Regulates protein traffic and performs metabolic functions in the cell
Includes: Plasma membrane Nuclear membrane Endoplasmic reticulum Golgi apparatus Vacuoles Lysosomes

10. INSULIN being released by pancreas cells using exocytosis

12. cis = (receives vesicles by fusion)
Golgi apparatus Cisternae = Flattened membrane sacs (look like stacked pancakes) 2 sides = 2 functions
cis = (receives vesicles by fusion)
trans = buds off vesicles to send to other places (shipping face)

14. Animation from: http://www.franklincollege.edu/bioweb/A&Pfiles/week04.html
See a Golgi movie

15. EVERYTHING’S CONNNECTED!

16. LYSOSOMES (common in animal cells but rare in plant cells)
Contain hydrolytic enzymes for intracellular digestion
Food (Phagocytosis)
Damaged organelles AUTOPHAGY ~ “eating self”
See movie

18. LYSOSOMES: Uncontrolled release of lysosome contents into the cytoplasm can also cause cell death (necrosis)
APOPTOSIS (self-destruct mechanism) “cell suicide”
Embryonic development
Removes damaged cells
Immune response
Cancer cells and AIDS virus override self-destruct signals

19. WHITE BLOOD CELLS USE LYSOSOMES TO DIGEST ENGULFED BACTERIA (Phagocytosis)

21. ANIMAL VACUOLES & VESICLES “transport vehicles”
FOOD VACUOLES Phagocytosis/ fuse with lysosomes
CONTRACTILE VACUOLES Freshwater organisms pump out excess water

22. PLANT VACUOLES (Central Vacuole)
Surrounded by membrane = TONOPLAST Selectively permeable – controls what goes in & out
STORAGE
Water
Stockpile proteins/inorganic ions
Deposit metabolic byproducts
Store pigments
Store defensive compounds against herbivores

23. Other cell parts with membranes that are NOT part of the Endomembrane system:
Mitochondria
Plastids
Peroxisomes

26. MITOCHONDRIA- DOUBLE MEMBRANE Outer membrane Inner membrane (CRISTAE)
increases surface area for chemical reactions
Intermembrane space= Space between inner membrane & outer membrane
MATRIX = Space inside cristae folds contains DNA, enzymes, ribosomes

29. Chloroplasts – site for photosynthesis in plants
DOUBLE MEMBRANE
Has own DNA
Thylakoids – membrane sacs containing light-capturing pigments
Grana – closed compartments of stacked thylakoid membranes
Stroma – fluid surrounding thylakoids

30. PLASTIDS CHLOROPLASTS- contain pigment chlorophyll for photosynthesis
CHROMOPLASTS- contain pigments that give fruits and flowers colors
AMYLOPLASTS- store starch (amylose) in roots and tubers (colorless)

31. Who else has a circular chromosome not
found within a nucleus?

32. Originally proposed in early 1900’s
Endosymbiotic Theory
Originally proposed in early 1900’s
Idea reintroduced in 1963 by Lynn Margulis
Suggests that engulfed prokaryotes shared symbiotic relationship with host cell
Advantages for both: ~ one supplies energy ~ other raw materials & protection

33. ENDOSYMBIOTIC THEORY See a movie about ENDOSYMBIOTIC THEORY

34. Evidence for Endosymbiotic theory
1. Mitochondria and chloroplasts have circular DNA like bacteria.
2. Mitochondria and chloroplasts have ribosomes whose size and structure resemble bacterial ribosomes.
3. Mitochondria and chloroplasts replicate independently of cell division using binary fission like bacteria.
4. Inner membranes of mitochondria and chloroplasts have a composition similar to bacterial membranes.

35. PEROXISOMES Other digestive enzyme sacs in both plants and animals
NOT part of endomembrane system (proteins come from cytosol)
In fat storing seeds (called GLYOXYSOMES) Break down fatty acids → sugars transport to mitochondria for energy
In LIVER CELLS Help detoxify alcohol & other poisons
PRODUCE HYDROGEN PEROXIDE (also a TOXIN) but have enzyme (CATALASE) to break this down
H2O2 → H2O + O2