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Every living thing has what 3 things?
- 1. DNA
- 2. Ribosomes
- 3. Plasma Membane
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5 Main Parts of Prokaryotic Cell
- Ribosomes
- Plasma Membrane
- Cell Wall
- Nucleoid Region
- Microtubules
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3 Parts of the Nucleus
- 1. Nuclear Envelope (membrane) - Double membrane - perforated by Nuclear Pores
- 2. Nucleolus - rRNA is synthesized from instructions in the DNA; ribosomal subunits are assembled from proteins and rRNA (moved out into cytoplasm then assembles into a ribosome)
- 3. Cromatin - a complex of protein and DNA -visible as Chromosomes in a dividing cell (human cells have 46 chromosomes excent sex cells which have 23)
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Endoplasmic Reticulum
- Endoplasmic - within the cytoplasm ; reticulum - little net
- extensive membrane network that continues off the nuclear envelope
If cell needs more membrane, ER pinched off a part (contains phospolipis & ribosomes) called a vacuole
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Ribosomes
- made of rRNA and protein
- they carry out protein synthesis
- FREE RIBOSOMES - suspended in the cytosol - make proteins that operate in the cytoplams - for example, enzymes to break down sugar
- BOUND RIBOSOMES - bound to the ER and nuclear envelope - make proteins destines for insertion into membranes (packagine with organelle such as lysosomes)
- Free and bound are structurally the same and can change places...they produce different kinds of proteins
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Smooth ER
- 1) Synthesize lipids - steroids are lipids that are viral to hormones. Areas that produce hormones (testes and ovaries) have lots of smooth ER
- 2) Store Calcium ions Ca+ (used in muscle contraction) muscle cells have extra smooth ER
- 3) Detoxify certain drugs in the liver - (lots of smooth ER in the liver) - phenobarbital and other barbituates (seditives) - methanphetimines
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Manufacturing Organelles
- 1. Nucleus
- 2. Ribosones
- 3. Rough ER
- 4. Smooth ER
- 5. Golgi Bodies (apparatus)
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Golgi Bodies (Golgi Apparatus)
- warehouse, shipping center, refinishing center.
- Takes in products of the ER, such as protein - modifies, stores and releases them
- Cis face - usually near ER- take in transport vesicules
- Trans face - shipping side - vesicules form and leave golgi, carrying specific proteins(enzymes) to other locations or to the plasma membrane for secretion
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Breaking Down and Recycleing Organelles
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Lysosomes
- sac of hydrolytic enzymes that an animal cell uses to digest macromolecules
- Made by rough ER and transferred to Golgi for further processing
- USES DIFFERENT ENZYMES TO PERFORM 3 FUNCTIONS
- 1. Destroy Invaders - when white blood cells attack bacterium, lysosomes release enzymes that break down the invader
- 2. Recycle -uses enzymes to recycle parts of organelle that are no longer functioning - break down and reuse materials
- 3. Digest - uses enzymes to digest food in a food vacuole
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Peroxisomes
- uses enzymes to break things down (fatty acids)
- in the liver detoxifies alcohols - produces hydrogen peroxide as a byproduct then converts it to water
- If there is too much alcohol pH changes and denaturation occurs
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Cytoskeleton
- skeleton of the cell
- 1) Microtubules - hollow tubes -flagella - CENTROSOME AND CENTRIOLES
- 2) Intermediate Philiments - supports nucleus
- 3) Microphiliments - solid rods
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Centrosome and Centrioles
- a) centrosome - microtubules grow out from the centrosome (animal cells) centrisome is near the nucleus and is a microtubule orgaizine center
- b) centrioles - in the centrosome is a pair of centrioles - each centriole is composed of 9 sets of triplet microtubules arranged in a ring
- Plants to not have centrioles
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Mitochondria
- converts energy to a form that the cell can use for work
- Cellular respiration - the process that generates ATP by extracting energy from sugars, fats,and other fuels with the help of oxygen
- HAS A DOUBLE MEMBRANE Inner membrane is folded around the CRISTAE extra surface area to make more ATP
- also has its own DNA but only from maternal lines - Mitochondrial DNA
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Endosymbiosis
- symbiosis on the inside - symbiotic relationship
- mitochondria and chloroplasts used to be eukaryotic cells
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Chloroplast
- plants and algae
- sites of photosynthesis - use solar energy and convert it to chemical energy by the systhesis of organic compounds such as sugars from carbon dioxide and water
- HAS A DOUBLE MEMBRANE
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2 organelles that used to be prokaryotic cells
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Cell Theory
- 1800's
- orgaisms made of cells
- cell is simplest collection of matter that can live
- cell structure = cell function
- cells are related by their descent form earlier cells
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who Invented the Light Microscope?
Anton Leeuwenhoek - 1590
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LM
- Light microscope - visible light passes through a specimen then glass lenses which magnify the image
- *Only microscope that can be used to see living organisms*
- up to 1000 times actual size
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EM
SEM
TEM
Electron Microscope - 1950 - insted of light shoot beam of electrons
SEM - Scanning Electron Microscope - specimin coated in gold - looking at outside surface 3D
- TEM - Transmission Electron Microscope - look at interior structures - have to embed specimin with heavy metals and take thin slices
- *used to learn about mitochondria in recent years
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Cell fractionation
- takes cells apart and separates the major organelles form one another - allows scientists to study function of organelles
- *uses centerfuge*
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Protists
single celled eukaryotes - amoeba
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Magnification
ratio of an object's image size to its real size
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Resolution
measure of the clarity of the image - minimum distance two points can be separates and still be distinguished as two points
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Contrast
accuntuates differences in parts of the sample - staining or labeling cell components
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Plasma Membrane
semi-permeable, selective barrier - allows oxygen, nutrients, and waste through...doent let others pass
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Plasmodesmata
- openings from one cell into amother so that signal proteins and electrical impulses can move between cells
- *only in plant cells*
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Gap Junctions
- channels from one cell to another that allow ions, sugars, amino acids to pass through. Gap junctions are important for communication between cells
- *only animal cells*
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Central Vacule
- *only plant cells*
- 1) Give shape to the cell
- 2) Stores water
- 3) Stores and breaks down waste
- 4) Can contain chemical defenses (milkweed plant)
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Sequestered
orgaisms that take a part of amother organism and make it part of themselves to protect them (Sea Slugs & Monarch Butterflies)
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Mimicry
- orgaisms that look like bad things will be protected (Monarch Butterfly)
- Batesian mimicry - Model & Mimic - one is good to eat..one is bad
- Mullerian mimicry - both are bad tasting
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Aposematic Coloration
bright colors to warn preditors to stay away
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Curare
poison from frogs - used for dart guns - we use for anastesia
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