Biology 172 Lecture 8

Home

Get App

Create

Deoxyribose in DNA lacks a ______ atom on ____
- oxygen
- 2'C
DNA molecules
- H-bonds between bases
- Complementary base-pairing
- Anti-parallel strands
- Double helix
- Secondary structure
Hydrogen bonds form between _-_ pairs and _-_ pairs in DNA
- G-C
- A-T
The secondary structure of DNA

is a double helix made up of two anti-parallel stands
How cells are studied
- Microscopy
- Cell fractionation
- Selective disruption, inhibition. perturbation
Light Microscope

contrast resolution
Electron Microscopy

Uses a beam of electrons instead of light to create an image
What is the difference between Prokaryotic and Eukaryotic cells
- Proks lack nuclear membrane
- Proks lack organelles
- Proks are usually much smaller
Structures in All Cells
- Plasma membrane
- Cytoplasm
- Ribosomes
- Regions with DNA
- Extracellular structures
Structures in Prokaryotic Cells
- Plasma membrane
- Cytoplasm
- Ribosomes
- Regions with DNA
- Extracellular structures
Plasma Membrane
- all cells
- provides a selectively permeable barrier: boundary and filter
- phospholipid bilayer
Cytoplasm
- all cells
- everything inside the cell (except nucleus)
- cytosol - fluid portion of cytoplasm - including dissolved molecules
Ribosomes
- all cells
- protein-RNA complex (molecular machine) that functions in protein synthesis
- not considered organelles)
- All cells translate genetic information into protein in the same way
Nucleoid
- prokaryotes
- area where chromosome is located
- includes a single circular chromosome
Plasmids
- prokaryotes
- small circular DNA molecules
Extracellular Structures (in prokaryotes)
- Capsule
- -for protection
- -gelatinous polysaccharide
- Pili
- -adherence
Extracellular Structures - Motile
- Flagella
- -some bacteria
- -many unicellular eukaryotes (protists) and some plants and animals
- Cilia
- -many unicellular protists and some plants and animals
- -Large number per cell
Cell Wall
- Most cells (proks and euks) except animals
- For rigidity (cell shape) and protection from mechanical damage
- Made of polysaccharides and proteins
- -cellulose in plants
- -chitin in fungi
- -peptidoglycan in bacteria
Extracellular Matrix (ECM)
- Characteristic of animal cells
- ECM = glycoproteins secreted by cells
- -collagen
- - other proteoglycans
- Integral membrane proteins in the plasma membrane link the ECM to the cell's internal cytoskeleton
Information processing in nucleus
- matter processing
- synthesis
- export
- recycling
Compartmentalization in Eukaryotic cells
- Segregation
- Concentration
Nuclear Region in Eukaryotes

location of most genetic material
Nucleus
- Organelle containing the chromosomes
- the site of ribosome production
- location of most genetic material
- Surrounded by nuclear envelope
- Contains filaments that maintain its shape and organization
- floats in nucleoplasm
Nuclear envelope

two membranes with pores (nuclear pores)
Matter processing - disposal, degradation
- cytoplasm
- lysosomes
- vacuoles
- peroxisomes
Lysosome
- some eukaryotes
- small digestive organelle
- contains hydrolytic enzymes to break down macromolecules
- involved in autophagy (breakdown of cytosolic particles and defective organelles) and phagocytosis (break down of extracellular particles)
Phagocytosis

lysosome digesting food
Authophagy

lysosome breaking down damaged organelle
Vacuole
- some eukaryotes esp. plants
- organelle with diverse functions ... including ion storage, water regulation, and degradation
- similar to lysosome

Author

clintave

131233

Card Set

Biology 172 Lecture 8

Description

Biology 172 Lecture 8 exam review

Updated

2012-01-28T22:30:19Z

Show Answers