47 terms

AP Biology Chapter 6

AP Biology Chapter 6. Glastonbury High School. Sabnis-Samboy. From Ch. 6 Study Guide.
Difference between magnification and resolving power
Magnification: ration of object's image to its real size
Resolving Power: measure of clarity of image
Two Domains of Prokaryotic Cells
a) Bacteria
b) Archaea
Pro-vs.-Eukaryotic Cells
Eukaryotic Cell: DNA stored in nucleus
Prokaryotic: DNA stored in non-enclosed region called nucleoid
Cell Wall
rigid structure, outside the plasma membrane (PLANT CELLS ONLY)
--Three functions--
1. protects plant cels
2. maintains its shape
3. prevents excessive uptake of H2O
Plasma Membrane
Membrane enclosing the cytoplasm
Prokaryotic Cells: where DNA is Stored, not enclosed
interior of a prokaryotic cell
locomotion organelles of some bacteria
Surface Area to Volume Relationship
A high ration of SA toV important because of cell-environment interchange of materials
long, thin projections on neurons and intestinal cells, increasing surface area but not volume
Nuclear Envelope
encloses nucleus,separating it from cytoplasm, two layers=connected=nuclear matrix
Nuclear Lamina/Nuclear Matrix
Lamina: net-like array of protein filaments, maintains shape of nucleus by supporting nuclear envelope
Matrix: framework of fibers extending throughout nuclear interior
made of proteins and DNA
cell prepares to divide, fibers condense to form two distinct chromosomes
made of chromatin
visible when cell divides
ribosomal RNA (rRNA) are assembled here
carry out photosynthesis
made of proteins, rRNA
Can be free or bound to rough ER
Endomembrane System
Nuclear Envelope
ER (Smooth and Rough)
Golgi Apparatus
cavity between membrane and cytosol
Transport Vesicles
travel to Golgi Apparatus, carry materials, proteins
Smooth ER Functions
- Synthesis of Lipids (oils, phopholipids, steroids (inc. sex cells))
- Metabolism of Carbohydrates
- Detoxification of Drugs/Poisons - Add hydroxyl groups to make soluble to flush from body
continuous with nuclear envelope
Rough ER
acts as membrane factory for cell
continuous with nuclear envelope
Golgi Apparatus
1. Vesicles move from ER to Golgi
2. Vesicles coalesce to form new cis golgi cisternae
3. Cisternal maturation
4. vesicles form and leave golgi for other locations with proteins
5. vesicles transport some proteins backwards to less mature cistern
6. Vesicles transport back to the ER
stacks of flattened membraneous sacs
cis, trans faces (polarity)
Postal Service Organelle
membranous sacs of hydrolytic enzymes that an animal cell uses to digest macromolecules
breakdown damaged organelles for recycling
a damaged organelle surrounded by double membrane, lysosome fuses with outer membrane of vesicle, lysosmal enzymes dismantle. process complete
Vacuole Types
Food Vacuoles: formed by phagocytosis
Contractile Vacuoles: pump excess water from cell
Central Vacuoles (PLANTS ONLY): Materials stored
1. proteins
2. pigments
3. poisonous materials for defense
membrane bound, digestion, storage, waste ect.
assist in cellular respiration
founded by double membrane, inner membrane with infoldings
site of photosynthesis (PLANTS ONLY)
two membranes around fluid stroma (made of membraneous thlakoids stacked ion grana)
detoxify alcohol and other harmful components
network of fibers that organize structures and activities in the cells

1. Support
2. Motility
3. Regulation
3 Fibers of Cytoskeleton
a. Microtubles
b. Microfilaments
c. Intermediate Filaments
1. Maintain cell shape
2. Cell motility
3. Chromosome movements in cell division
4. Organelle movements
Centrosome = organizing center for microtubules Centriole = two make up the centrosome ANIMALS CELLS
Cilia vs. Flagella
Cilia: rowing like pattern
Flagella: undulating motion
Both have core of microtubles sheathed in an extension of plasma membrane
Dyneins (motor proteins)
large contractile protein in cilia and flagella, ATP hydrolysis changes its shape
Functions of Microfilaments
a. Changes in cell shape
b. muscle contraction
c. cytoplasmic streaming
d. cell motility
-- Motor Proteins for microfilaments --
myosin proteins
Functions of Intermediate Filaments
a. anchorage of nucleus and certain other organelles
b. Formation of nuclear lamina
Composition of Cell Wall
consists of microtubles embedded into a matrix of other polysaccharides and proteins
Primary Cell Wall
first wall secreted, thin and flexible
Middle Lamella
thin layer rich in sticky polysaccharides called pectins, found between primary cell walls of adjacent cells
Secondary Cell Wall
deposited in several laminated layers, strong and durable matrix that provides protection and support
allow transportation between non-living cell walls of plant cells through these channels, called plasmodesmata
Extra-Cellular Matrix (ECM) Components
1. Collagen - Fibers are embedded iota web of proteogycon complexes
2. Fibronectin - attaches to ECM to integrins embedded in the plasma membrane
3. Proteoglycon Complex - consists of hundreds of proteogylcon molecules attached non-covalently to a long polysaccharide chain
4. Integrins - membrane proteins with 2 subunits, linkage sends signals from cell to exterior to adjust cell behavior
Plant Cell Intercellular Junctions
Plasmodesmata, water and small solutes may pass
Animal Cell Tight Junction
waterproof tight seal prevents leakage of extra celular fluids
Animal Cell Desmosome
like rivits, strong sheets of muscle cells to each other
Animal Cell Gap Junction
similar to plasmodesmata, ions, sugars, amino acids pass through - in communication with the heart
holds DNA, surrounded by nuclear envelope, nuclear pores, houses chromosomes, contains nucleoli, where ribosomal subunits are made