Exam 1 Review Flashcards
What is the “Cell Theory” of life?
- All organisms are composed of cells
- Cells are the structural unit of life
- Cells arise only from other cells
Biologists generally agree that living cells all must have…
- A limiting boundary (plasma membrane = cell membrane)
- Carry out complex metabolism (chemical reactions)
- A mechanism of inheritance (DNA, RNA?)
Are viruses living cells?
No, they are not living cells. Lack basic machinery for self replication. Dependent on host cell functions for propagation.
Define Autopoietic
system capable of reproduction and self maintenance
what are the 3 domains of life?
- Archaea
- Bacteria
- Eukarya
What is Archaea?
archaebacteria, prokaryotic, has unique rRNA. Mostly anaerobic, lives in extreme environments (high temps, strong acids)
What is Bacteria?
prokaryote, peptidoglycan cell wall.
What is Prokarya (prokaryotes)?
“Before nucleus”
What is Eukarya?
cells with “true nucleus”, cells with 1-2 flagella. Consist of animal, plant, fungi, protista kingdoms.
What can Light microscopy view?
living or chemically fixed cells if dead, unstained or stained. Movements of living unstained cells.
cannot resolve individual molecules, but can determine where they are.
What is fluorescence microscopy?
type of light microscopy. Used to visualize 1 component (eg. protein) in a cell.
process: stain specimen w dye. light excites the dye, which then emits its light, a filter only lets this filtered light through.
images are color on black background.
what is Immunofluorescence microscopy
type of fluorescence microscopy.
uses antibodies to view protein localization
only dead cells can be viewed
only proteins of interest are visible, rest of cell is dark.
cannot resolve individual antibodies, 4 used for red & green.
what is GFP?
Green Fluorescent protein, in fluorescense microscopy. fused onto protein of interest to follow proteins in living cells. Done by manipulating DNA sequence, chimeric.
What is a TEM?
transmission electron microscope.
Resolve small objects
What is SEM?
Scanning Electron Microscope, reveals details of cell surface.
grayscale pictures.
What are prokaryotes?
bacteria and archaea domains. Many shapes but mostly small.
human body has more prokaryotic cells than eukaryotic cells.
What type of wall do Bacteria have?
peptidoglycan layer cell wall, outside plasma membrane.
Eukaryotic cells have many…
compartments. Metabolic processes segregated from one another.
what is the difference between cytoplasm and cytosol?
Cytoplasm = everything inside plasma membrane, cytosol + organelles Cytosol = (fluid) everything inside plasma membrane and outside organelles.
What was the very first orgnalle?
Nucleus. Process of invagination
What is the C value paradox?
the amount of DNA content of a nucleus does NOT mean a complex organism.
What is the difference between plant and animal cells?
plant cells (only) have vacuole, cell wall and chloroplasts.
What is a vacuole?
plant cell containing majority of volume of the cell, exerts turgor pressure.
What is the cell wall?
gives the cell is strength and rigidity. resists turgor pressure.
What constraints does a cell wall pose?
no cell movement/migration, no division, or cell to cell communication.
What is a chloroplast?
the photosynthetic organelle of plant cells
what is the origin of mitochondria and chloroplasts?
arose by endosymbiosis of bacterial cells.
What is a ‘fact’ in science?
a hypothesis that has been tested many times and cannot be rejected
What tenant of the cell theory is violated by the origin of life?
that all cells come from other cells.
What was the evolution of first cells?
RNA-> (translation) -> RNA + protein -> (transcription -> DNA + RNA + protein
Cell evolution likely sequence of events
- Photosynthesis evolved first, to build of O2
- formation of nucleus by membrane invagination
- respiration evolves in prokaryotes
- acquisition of mitochondria by endosymbiosis
- acquisition of chloroplast by endosymbiosis
Why would RNA come before DNA?
because RNA can also act as an enzyme.
What came first mitochondria or chloroplasts?
mitochondria
Is covalent bond a strong or weak bond?
strong bond, formed when atoms share pairs of electrons
example C-C
Is an Ionic bond strong or weak?
considered weak, because we are in an aqueous environment.
definition Stealing of electrons to make bond
Is a hydrogen bond strong or weak?
weak.
What is a polar covalent bond?
allow Hydrogen bonds, through partial negative charges with proton
How can macromolecules for a strong interaction?
through many weak chemical interactions, H or ionic bonds.
What chemical group is Alcohol?
HO-C bond, hydroxyl, hydrophilic
What chemical group is an Aldehyde?
O=C-H carbonyl group,
What chemical group is a ketone?
O= C - C
What makes up a carboxylic acid?
O=C-OH
What makes an Ester?
O=C-OH CH3 carboxylic acid + alcohol
What is an Amine?
NH2 - C
What is an Amide?
O=C-OH + NH2-C -> amide, protein structure
What is phosphoanhydride?
bonding of 2 Phosphates together
How does phosphoanhydride provide energy?
when 3 phosphates are bonded together in ATP, the break of the last 2 bonds provides energy for RNA and DNA
How do you create an Phosphate Ester?
bonding of hydroxyl/Alcohol with phosphate
How do you create an Acyl Phosphate?
bonding of carboxylic acid (O=COH )with phosphate
What are the 4 major groups of macromolecules?
Lipids, proteins, polysaccharides and nucleic acids
What are the building blocks for macromolecules?
Sugars (monosaccharides), fatty acids, amino acids, nucleotides
What is a condensation reaction?
a bond is formed and water is released.
Monomer to Polymer
What is a hydrolysis reaction?
a bond is broken.
Polymer to a monomer
What is the difference between an aldose and a ketose?
Aldose O=CH at end of chain, Ketose O=C is not at the end.
Are polysaccharides hydrophilic or hydrophobic?
Hydrophilic
What is the difference between an alpha and beta hydroxyl ring?
Beta has OH on top, Alpha has OH on bottom