Bio Chapter 4 notes
Intro to Microscopy
Microscopy
- studying cells using a microscope
- animacules
- microbes
- Pathogen
- Anything that causes disease
- \
People!
- Robert Hooke
- responsible for first compound light microscope
- 1665
- He looked at mono-tissue
- xylem tubes
- looked like Monk rooms
- where we get word Cell
- Leeuvenhoek
- Made the first simple microscope
- 1648
- From the Netherlands
- textile tradesman
- Robert Brown
- started cell staining
- 1831
- to see organelles that are normally invisible
- Schleiden
- Botonist
- said that all plants were made of cells
- Schwan
- Zoologist
- said all animals were made of cells
- Virchow
- Physician
- Disproved spontaneous generation
- Cell theory
- Made by royal society
- Schleiden
- Schwan
- Virchow
- 3 statements
- all living things are made of cells
- cell is a basic unit of life
- all cells come from pre-existing ones
Cells under the microscope
- types of microscopes
- Compound light microscopes
- portable
- leaves alive things unharmed
- limited magnification
- micrometer
- Electron microscopes
- TEM
- 10,000,000x
- 2d pics
- electron beam
- nanometers
- SEM
- 500,000x
- 3d pics
- coats thing with metallic spray
- nanometers
- Why are cells so small?!
Organelles
Plasma Membrane
- function
- Boundary between inside and outside of cell
- provides cell identification
- Characteristics
- Selectively permeable
- phospholipid bilayer with imbedded proteins
- Hydrophobic tails/p=hydrophilic heads
- Nonpolar cholesterol
- allows movement
- liquid-mosaic
- Carb chain on surfaces
- glycoproteins, identifier of cell
Nucleus
- function
- stores dna
- Characteristics
- double membrane (nuclear envelope)
- pores for rna
- Chromatin/chromosome (DNA)
- loose/coiled
- DNA organized into genes
Nucleolus
- function
- makes new ribosomes
- characteristics
- in the nucleus
Mitochondria
- Function
- produces atp through CR
- characteristics
- Double membrane
- outer
- cristae
- filled with matrix
- can change shape
Ribosomes
- function
- make polypeptide chains
- dumps to ER
- characteristics
- 2 subunits
- free, or on ER
Endoplasmic Reticulum
- function
- transports proteins as they fold
- steps 2 and 3
- Pinches off vesicle and dumps to golgi
- characteristics
- continuum of nuclear envelope
- rough or smooth (ribosomes/none)
Golgi Apparatus
- function
- Sorts and packages final proteins
- step 4
- produces lysosomes
- characteristics
- looks like a stack of pita bread?
Lysosomes
- function
- contain digestive enzymes
- digest unwanted stuff
Cytoskeleton
- function
- maintain cell shape/internal walls
- characteristic
- 3 types of fibers
- microtubuoles
- microlilloment
- actin
- parts and dis/reassemble fast
Cilia
- function
- provide cell movement
- char
- short, many of them
Flagella
- function
- provide cell movement
- char
- long, few of them
Cell wall (plants)
- function
- outerbarrier/support
- char
- made of cellulose
Vacuole(plants)
- function
- contain water
- char
- biggest organelle in a plant cell
Chloroplast
- function
- where photosynthesis occurs
- char
- 2 outer membranes
- has a 3rd membrane, Thylakoid
- stack = granum
- stroma
- area outside thylakoid but inside membrane
2 Main types of cells
Prokaryotic
- bacteria
- 3.5 bya
- not covered/protected
- no defined nucleus
Eukaryotic
- 2.2 bya
- membrane bound
- defined nucleus
- compartmentalization
Central Dogma
Chromosomes
- received from sperm and egg
- 23 each
Genes
- imbedded on chromosomes
- cant leave the nucleus
- bc dna is double helix
RNA
- travels to worksite
- fits through nucleus bc 1 helix
Ribosome
- reads code from gene
- translates into polypeptide
protein
- make trait happen
trait