High Yield Biology Flashcards
What are viruses made up of?
Genetic Material
Protein Coat
Sometimes, an envelope containing lipids
Protein coat of a virus is called
Capsid
Are enveloped viruses easier or harder to kill than non-enveloped and why?
Easier because the envelope is sensitive to heat, detergent, and desiccation
Why are viruses considered obligate intracellular parasites?
Because they cannot reproduce on their own
What are virions?
Viral progeny that are released to infect additional cells
Bacteriophages are?
Viruses that specifically target bacteria
What additional structures does a bacteriophage have?
Tail sheath - syringe to inject genetic material
Tail fiber - recognize and connect to host cell
Positive sense viral information?
Single stranded RNA virus who’s genome can be directly translated to functional proteins
Negative sense viral information?
Single stranded RNA virus who’s genome must be synthesized by RNA replicase into a complementary strand which can then be translated into a functional protein
What additional thing must a negative sense RNA virus contain?
RNA replicase
Retrovirus life cycle
Single stranded RNA virus that contains reverse transcriptase which synthesizes DNA from the RNA strand and the DNA is then integrated into host cell’s immune system
What additional thing must a retrovirus contain?
Reverse transcriptase
Productive virus life cycle
Keeps the host cell alive and virus leaves through extrusion - virus can keep using cell machinery
Lytic cycle
Bacteriophage reproduces and fills cell with virions and then the cell lyses and other bacteria are infected
Virulent Viruses
In lytic cycle
Lysogenic cycle
Virus integrates into the host genome and is replicated as the bacteria reproduces
Provirus
In lysogenic cycle
Prophage
In lysogenic cycle
What are prions?
Infectious proteins
Are prions living things?
No
How do prions cause disease?
Trigger the misfolding of other proteins - for example, conversion of alpha-helix to beta-sheet
What are viroids?
Small pathogens of a short circular single-stranded RNA that infect mostly plants
How do viroids cause disease?
Bind to a large number of RNA sequences to silence genome - results in metabolic and structural damage
How many cells are prokaryotic organisms?
Single-celled
Is the nucleus bound by a single or double membrane?
Double
What happens in the nucleolus?
Ribosomal RNA (rRNA) is synthesized
What are histones?
Organizing proteins around which linear DNA is wound
How many membranes does the mitochondria have?
Two - outer is a barrier between the cytosol and inner environment, inner contains the electron transport chain
What are the folds of the inner mitochondrial membrane called?
Cristae
Intermembrane space (mitochondria)
Space between the inner and outer membranes
Space inside the inner mitochondrial membrane?
Mitochondrial matrix
Which direction are protons pumped during the electron transport chain and what does this create?
From the matrix to the intermembrane space to generate the proton-motive force - protons then flow through ATP synthase to generate ATP
What makes the mitochondria semi-autonomous?
Contain some of their own genes which they replicate independently of the nucleus via binary fission
Where did mitochondria originate from?
Engulfing an aerobic prokaryote by an anaerobic prokaryote
Lysosomes are responsible for?
Breaking down substrates with hydrolytic enzymes
What organelle do endosomes often function in conjunction with?
Lysosomes
What do endosomes do?
Transport, package, and sort cell material travelling to and from the cell membrane
How does autolysis occur?
Release of lysosomal enzymes to cause apoptosis
Does the endoplasmic reticulum have one or two membranes?
Two
Where are proteins translated that are directed towards the cell itself?
Rough ER
Where are proteins translated that are directed outside the cell?
Cytoplasm
What are the roles of the smooth ER?
Lipid synthesis
Detoxification of drugs and poisons
Transport proteins from RER to golgi
Which organelle modifies and sorts its products?
Golgi
What organelles contain hydrogen peroxide?
Peroxisomes
What is the function of peroxisomes?
Breakdown of long-chain fatty acids through Beta oxidation
What makes up microfilaments?
Actin
What does actin interact with to create movement force?
Myosin
What cytoskeletal structure plays a role in cytokinesis?
Microfilaments
What makes up microtubules?
Tubulin
Is actin or tubulin hollow?
Tubulin
Which motor proteins do microtubules interact with?
Kinesin and Dynein
What cytoskeletal structure make up cilia and flagella?
Microtubules
What general structure do cilia and flagella have?
9+2
9 microtubule doublets surrounding 2 central microtubules
What are centrioles?
Microtubule organizing centers
Where are centrioles found?
Centrosome
What general structure do centrioles have?
Nine triplets of microtubules with a hollow center
Which cytoskeleton components increase rigidity of the cell and anchor organelles?
Intermediate filaments
What cell type makes up the majority of functional cells in an organ?
Epithelial tissue
Basement membrane
Layer of connective tissue beneath epithelial cells
What does it mean that epithelial cells are polarized?
One side faces the lumen (inside of organ or tube) and the other faces blood vessels and structural cells
Simple epithelia
One layer of cells
Stratified epithelia
Multiple layers of cells
Psuedostratified epithelia
Appear to have multiple layers due to differences in height but actually only have one
Squamous epithelial cells are shaped like?
Flat and scalelike
What does connective tissue mostly make up?
Support structure
Stroma is?
Support structure
Spherical bacteria
Cocci
Rod-shaped bacteria
Bacilli
Spiral-shaped bacteria
Spirilli
Metabolic process of obligate aerobes?
Require oxygen
Metabolic process of obligate anaerobes?
Cannot survive in environments with oxygen
Metabolic process of facultative anaerobes?
Can survive in environments with and without oxygen
Metabolic process of aurotolerant anaerobes?
Cannot use oxygen for metabolism but can survive in the presence of oxygen
Envelope of a bacteria?
Cell wall and cell membrane
What color do gram-positive cells turn?
Purple
What color do gram-negative cells turn?
Pink/red
Do gram positive or negative cells have a thicker cell wall?
Positive
Chemotaxis
Moving in response to chemical stimuli
Are prokaryotic or eukaryotic ribosomes bigger?
Eukaryotic
By what process do single-celled eukaryotic cells multiply?
Binary fission
Bacterial transformation
Genetic material from surroundings is picked up and incorporated into the genome
Bacterial conjugation
Transfer of genetic material from one bacterium to another via conjugation bridge
Bacterial transduction
Transfer of genetic material via a bacteriophage
Transposons
Genetic elements that can insert and remove themselves from the genome
Is mitochondrial DNA single or double stranded?
Double
Glucogenesis?
Creation of glucose from glycerol and amino acids (from protein breakdown)
What is ketone body synthesis?
Use of fatty acids as a source of fuel
What is a test cross?
Use a homozygous recessive to determine is a dominant phenotype is homo or heterozygous for trait
Which nucleic acids are pyrimidines?
C and T
Which nucleic acids are purines?
G and A
Are pyrimidines one or two ringed?
One
Are purines one or two ringed?
Two
What type of hormone is insulin?
Peptide
Do eukaryotic fatty acids have an even or odd number of C?
Even
Do eukaryotic fatty acids have cis or trans double bonds?
Cis
When does an oocyte complete meiosis?
After fertilization
Is a g-protein coupled receptor on the surface or intracellular?
Surface
Do erythrocytes have mitochondria?
No
Equation for DeltaG with Keq
DeltaG=-RTlnKeq
What enzyme changes structure to be activated?
Zymogen
Which end of DNA does synthesis start at?
3’
What (R) / (S) configuration do amino acids have and what is the exception?
(S) Cysteine is (R) because S group is higher priority
What enantiomer are all amino acids in eukaryotes?
L-amino acids
Can d amino acids exist?
Yes just in prokaryotes
Which amino acid is not chiral?
Glycine
What does the titration curve of an uncharged amino acid look like?
Starting at very low pH, amino acid is +1 (fully protonated)
First straight portion around pH of 2 for pKa of carboxylic acid
Vertical at pI ~6 when amino acid is +0 (c-end is deprotonated)
Another straight portion around pH of 9 for pKa of amino group
At very high pH, amino acid is -1 (fully deprotonated)
What is the difference in titration curves for a charged amino acid compared to a neutral one?
An extra “step” for the third deprotonation of side group
What is the pI of an amino acid with a basic side chain?
Higher
What is the pI of an amino acid with an acidic side chain?
Lower
What is the vertical portion of a titration curve of an amino acid?
pI
What is the horizontal portion of a titration curve of an amino acid?
pKa
How many amino acid residues does an oligopeptide have?
<20
Primary protein structure
Linear sequence of amino acids
Bonds of primary protein structure
Peptide bonds
Secondary protein structure
Local structure of neighboring amino acids - alpha helix and beta sheets
Bonds of secondary protein structure
Hydrogen bonds
Alpha helix
Intramolecular hydrogen bonds between amino group of one amino acid and carbonyl 4 residues down the chain
What secondary structure makes up keratin?
Alpha helix
Beta Sheets
Intramolecular hydrogen bonds between amino group of one amino acid and adjacent carbonyl - can be parallel or antiparallel
What secondary structure makes up fibroin?
Beta sheets
What amino acid can disrupt secondary protein structure?
Proline
Tertiary protein structure
Three-dimensional shape of a single polypeptide chain stabilized by hydrogen bonds, hydrophobic interactions, salt bridges (acid-base interactions), and disulfide bonds
Does formation of a solvation layer increase or decrease entropy?
Decrease (unfavorable bc molecules are more organized, non-spontaneous)
What is a disulfide bond?
Two cysteine molecules are oxidized and form a covalent bond in csytine
Quaternary protein structure
Interaction between peptides in proteins that contain multiple subunits
What is a conjugated protein?
Protein with a molecule covalently attached
What is the covalently attached molecule on a conjugated protein called?
Prosthetic group
What type of protein is collagen?
Structural
What type of protein is elastin?
Structural
What type of protein is keratin?
Structural
What type of protein are cadherins?
Cell adhesion molecules, glycoproteins
What type of protein are selectins?
Allow cells to adhere to carbohydrates on cell surfaces - immune cells
Native PAGE gel electrophoresis
Maintains protein shape but is difficult to interpret due to different mass-to-charge ratios
SDS PAGE gel electrophoresis
Denatures proteins and masks the charge allowing for accurate size comparison but intact protein cannot be obtained
Isoelectric focusing
Electrophoresis in which protein migrates until a point where pH=pI
Bradford protein assay
Starts green/brown in its protonated form and turns blue in the presence of protein by protonating the protein
