Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
94 Cards in this Set
- Front
- Back
How do compound light microscopes work? |
Light is passed thru specimens and was refracted by lenses |
|
What is resolving power? |
The clarity or sharpness of the image is limited by the wavelength of visible light |
|
What is the limit of light microscopes? |
Limit of 0.2 micrometers |
|
How do electron microscopes work? |
Uses a beam of electron in place of light Magnents in place of lenses to focus the image |
|
What makes electron microscopy so accurate? |
Since the wavelength of electons is smaller, the resolving power is much greater |
|
How much more powerful is an electron microscope compared to CLM? |
Resolving power about 100x's more powerful that CLM |
|
Where does a electron microscope have to be? |
On the ground floor to prevent vibration interference |
|
When were organelles discovered? |
Organelles weren't discovered til TEM was invented in the 1950's |
|
What is an electron microscopes resolution? |
2 nanometers |
|
How do transmission electron microscopes work? |
Pass electons thru tissue for a 2D image |
|
What are TEM'S used for? |
Studies the internal structures of the cell |
|
What are the products of TEM's? |
Black and white image 2D image |
|
What has to be done to a specimen before being put thru a TEM? |
Specimen sliced, gold coated and studied in a vacuum, so no living specimens |
|
What are Scanning electron microscopes for? |
Studies the surface of structures |
|
How do SEM's work? |
Specimen covered in thin layer of gold Electrons bounce off the surface to be sensed in an xray Images are 3D |
|
What is a gentrification used for? |
Used for lysing cells |
|
What happens to the cell as the centrifuge spins? |
Cell separates into layers by density without damaging the parts Pellet and supernatant are separated and fluid is centrifuged again |
|
What do prokaryotic cells lack? |
Lack a nucleus |
|
Where is DNA in a prokaryote? |
DNA is concentrated in a region called the nucleoid (usually a single loop) |
|
What is the only organelle in a prokaryote? |
Ribosomes |
|
Where is DNA in a eukaryotic cell? |
Bound in the nucleus |
|
How is a eukaryotic cell organized? |
Organelles with similar functions are grouped together |
|
What are organellesm |
Region or structure where enzymes that work together are grouped |
|
Which is the only microscope able to see the nucleus? |
Compound light microscope |
|
What is the nuclear envelope? |
A double membrane that surrounds the nucleus |
|
What do the pores in the nuclear envelope do? |
The pores regulate the movement of molecules in and out |
|
What is the fluid in the nucleusm |
Nucloplasm |
|
What is nucleoplasm made of? |
Water, nucleic acids, and nucleotides |
|
What does chromatin become before nuclear division? |
Chromatin coils into thick chromosomes |
|
How do chromosomes vary between species? |
Chromosomes vary in size and number |
|
What does the nucleolus do? |
Synthesizes rRNA and protiens to build ribosomes |
|
What are chromatin made of? |
Only DNA |
|
What is chromatin used for? |
Active in replication and transcription |
|
How does chromatin become a chromosome? |
Chromitin is spooled around proteins (histone) |
|
When does chromatin become chromosomes? |
Only during meiosis or miosis |
|
What are ribosomes made of? |
Made of 2 subunits |
|
What are the 2 ribosome subunits? |
Large subunit and small subunit |
|
Where do the subunits of a ribosome assemble |
Outside of the nucleus |
|
What do ribosomes make? |
Site of protein synthesis |
|
What effects the abundance of ribosomes? |
Level of protein synthesis |
|
What do free ribosomes do? |
Free ribosomes make metabolic enzymes and protein for the cell |
|
What do bound ribosomes do? |
Bound ribosomes make proteins for organelles or secretion from the cell |
|
What is being in the ER equivalent to? |
Being on an assembly line |
|
What organelle are proteins synthesized? |
Rough ER |
|
What does the endoplasmic reticulum form? |
The cisternae from the surface of the nucleus |
|
What is the cisternae? |
An enclosed passageway through the cytoplasm |
|
What are the 2 sides of the ER? |
Cis and Trans |
|
What is the cis side of the ER closest to? |
Nucleus |
|
What is the Trans side of the ER closest to? |
The membrane |
|
What does the smooth ER synthesize? |
Lipid synthesis in the cell including oil, steroids and phospholipds |
|
What is the function of smooth ER? |
Lipid synthesis Metabolism of glycogen into glucose (liver) Detoxification of drugs & posions |
|
What are the functions of the Rough ER? |
Proteins made in cisternae for protection Proteins fold into their native form in cisternae New ER is made in rough ER from raw materials in cytosol Proteins leave the rough ER packaged in vessicals |
|
What does the Golgi apparatus do? |
Modify protein made in the ER before transporting them out of the cell (folds and packages) Adds carbohydrate chains (making glycoprotein) Directs release of vesicles towards specific regions of the cell |
|
Is the Golgi polar or non-polar? |
Polar |
|
Where are is the cis side and what does it do? |
Near ER and recieves the protein |
|
Where is trans side of the Golgi and what does it do? |
Near membrane and releases molecules in their modified form |
|
What molecule folds proteins in the Golgi? |
Chaparonin |
|
What was the first organelle discovered? |
Golgi apparatus |
|
What are the functions of lysosomes? |
Fuse to cell membrane to aid in phagocytosis Aid the cell in programmed cell death |
|
Where are lysosomes made? |
Made in the rough ER |
|
What is the inside of a lysosome like? |
Filled with enzymes involved in hydrolysis rxn Enzymes require low pH for optional rxn Maintains low pH (5) internally by active transport of hydrogen from the cytosol |
|
What is autophagy? |
Digest organelles into AA, FAC's and monosaccarides |
|
What causes lack of lysosome function? |
Storage diseases as lipids accumulate in the cell |
|
What is Tay-Sach's disease? |
Where your body can't metabolize lipids |
|
What do vacuoles do? |
Aid in storage and removal of compounds of the cell |
|
How are food vacuoles formed? |
Formed in endocytosis of food into the cell |
|
What do contractile vacuoles do? |
Aid in water balanced for produce by pumping water out |
|
What does a central vacuole do? |
Store water, pigments, waste or poisons in a "storage tank" within the cytosol |
|
What does the mitochondria do? |
Site of cellular respiration buy a series of reactions, that make ATP from glucose Harvest energy |
|
What makes mitochondrial proteins? |
Free ribosomes aid in making mitochondria proteins |
|
What is the outer membrane of the mitochondria made of? |
Phospholipid bilayer |
|
What is the cristae? |
·Convoluted inner membrane imbedded with enzymes ·Forms compartments for microenvironments inside and outside the cristae for the stages of cellular respiration |
|
Do chloroplasts contain their own DNA? |
Yes cDNA |
|
What is a thylakoid? |
The circular separate pieces in chloroplast |
|
What is granum? |
Thylakoid stacks |
|
What is the process of cellular respiration? |
Glucose + 6O2 ➡ 6CO2 + 6H2O + 36 ATP |
|
What does peroxidase do? |
Breaks down H2O2 ( hydrogen peroxide) into H2 and O2 |
|
What does the cytoskeleton do for the cell? |
Provides support and shape to the cell Aids in movement of organelles in the cell Aids in cell movement Aids in cell division |
|
What are microtubules? |
Hollow tubes of protein tubulin |
|
What are microfilaments? |
Thin, solid fibers of protein actin |
|
What do microtubules do? |
·Provides skeletal support as compression resistant girders ·Serve as tracks for organelles with motor molecules to move ·Form centrioles that bind the ends of the SFN |
|
What is a flagella? |
Few per cell undulate in movement |
|
What are cilia? |
Cover the cell surface and stroke-like oars |
|
How are microtubules arranged? |
Microtubules arranged in 9 + 2 pattern covered by p.m. and anchored to a centriole called the basal body |
|
What does dynein do? |
Contracts to alter the shape of the Cilia or flagella consumes ATP |
|
What do microfilaments do? |
Aid and changes in membrane shape for endocytosis and exocytosis Form pseudopodia by contracting the cell membrane |
|
What is endocytosis? |
Taking in nutrients |
|
What is an analogy for cellulose fibers? |
Cellulose fibers run through carbohydrate/ protein matrix as rebar runs through concrete |
|
What does a cell wall provide for plant and fungus cells? |
Shape Protection from excess water uptake Skeleton for the organism |
|
What does CAM stand for? |
Cell adhesion molecule |
|
What is plasmadesmata? |
Allows water to pass between cells |
|
What are tight junctions? |
Adjacent cells fused by tightly woven protein |
|
What are gap junctions? |
Provide channels for cells to communicate via cytoplasm |
|
What are adhesion junctions/desmosomes? |
Button-like proteins inside the cell membrane that secure protein fibers running between cells |