Exam 1 Flashcards
What are the properties of life?
-being highly organized
-homeostasis
-reproduction
-growth and development
-transforming energy
-response to stimuli
-adaption to environment
Who is credited for discovering and coining the term “cell”
Robert Hooke
What are the differences between eukaryotes and prokaryotes
P = unicellular, absent membrane-bound organelles, DNA in cytoplasm, circular chromosome, binary fission
What four elements compose about 96% of living matter?
carbon, hydrogen, oxygen, and nitrogen
What is a cation and an anion
cation = positively charged (ex: sodium)
anion = negatively charged (ex: chloride)
What are the four main groups of large organic molecules in cells
Carbohydrates, Lipids, Proteins, and Nucleic Acids
Why is the carbon atom a versatile building block of molecules
contains four valence electrons, which can form covalent bonds with four other atoms - ultimately being able to form many different molecules
What is hydrolysis
water is consumed as a reactant to break one larger molecule down into two or more new substances (ex: sucrose broken down to glucose and fructose monomers from water)
What is an Anabolic reaction?
building of larger complex molecules from smaller simpler ones
requires an input of energy
EX: formation of glycogen from glucose
What is a Catabolic reaction?
breaks complex molecules down into smaller components
releases energy
EX: cellular respiration (glucose and oxygen react to yield CO2 and water)
Why do cells not really defy the 2nd law of thermodynamics
Cells receive constant input of energy in the form of potential energy in chemical bonds (especially molecules like glucose)
Cells create order at the expense of heat generation - as energy is used, some energy is lost as heat to the environment. This heats up the cell’s surroundings, which adds to disorder
What is a biological example of the first law of thermodynamics
use of energy from sunlight in photosynthesis to be converted into chemical energy and stored in the form of glucose
What are Oxidation and Reduction and what is being oxidized in cellular respiration
Oxidation = loss of electrons
Reduction = gain of electrons
OIL RIG
Glucose is being oxidized in cellular respiration
What are the characteristics of enzymes?
-not consumed by the reaction
-physically bring the reactant together
-destroy chemical bonds
-provide microenvironment in the active site
-noncovalent bond with reactants
What is an example of a medicine that targets enzymes to treat human disease
Gleevec (imatinib)
inhibits the function of the BCR-ABL kinase, being a competitive inhibitor
Why are enzymes called catalysts
they speed up a chemical reaction
Will an exergonic reaction proceed immediately
No
Does spontaneous necessarily mean instantaneous
No - spontaneous refers to naturally occurring, not right away
Why is it beneficial to give someone ethanol if they have been poisoned with methanol
Ethanol will compete against methanol for the active site of Alcohol Dehydrogenase, meaning that it is a competitive inhibitor.
What are the parts of an amino acid’s structure
Amino Group, Carboxyl Group, R Group, Alpha Carbon (central carbon), Hydrogen atom
What is the difference between essential and non-essential amino acids
Essential = body does not produce, must come from diet
Nonessential = body produces
What are the three big categories of amino acids
Non-polar (e.g. leucine, glycine)
Polar (e.g. serine, tyrosine)
Electrically Charged (e.g. aspartic acid, lysine)
What is Primary Structure
-amino acid sequence
What is Secondary Structure?
polypeptides that can form an alpha-helix or beta-sheet
Hydrogen bonds
Can enclose a hydrophilic region of a protein so that the hydrophobic side chains are on the outisd
What are examples of Secondary Structure
Keratin (alpha-helices)
Silk (beta sheets)
insect/fish antifreeze proteins
What is Tertiary Structure
interactions between amino acid side chains
covalent, ionic, hydrogen bonds
What is Quaternary Structure
multiple subunits combine to form a complete protein structure
Disulfide bonds
Why do proteins fold
to minimize free energy and to move to a lower energy state
What are the importance of disulfide bonds
-added stability, flexibility
-found in structural proteins in ECM
What is a protein domain
a segment of the polypeptide/protein that folds into an independent compact structure
-a protein can have multiple domains
What is denaturation and how can it occur
modifying the molecular structure of a protein
physical and chemical changes can deactivate a protein - leaves only primary structure
through temperature, pH, salt
What are the structures that make up an antibody
heavy chain, light chain, disulfide bonds, hyper-variable region
How are antibodies used in the lab
to target or mark proteins for visual study (protein localization) and to sort specific proteins (protein purification)
What is an Allosteric protein
protein that has two or more conformations
*MOST PROTEINS ARE ALLOSTERIC
(ex: motor proteins)
What does a Kinase do
phosphorylate proteins (add a phosphate group)
What does Phosphatase do
dephosphorylates proteins (remove phosphate group)
What are GTP-binding proteins
nucleotide triphosphates can be used to regulate protein function
EX: odorant receptors
Why are misfolded proteins problematic
are prone to aggregation (begin to stack with one another) and cause molecular stress and interfere with cellular function
many neurodegenerative disorders
What are possible functions for normal prion protein
intracellular signaling
cell-cell adhesion
maintain myelin sheath of neurons
What is an activated carrier molecule
molecule carrying a chemical group in a high-energy linkage, serving as a donor of energy or of the chemical group in many other reactions
List 10 proteins and their functions
- Hemoglobin - transports substances through the body via the blood
- Actin - structure
- Myosin - muscle contraction
- Insulin - hormone signaling
- Amylase - break down nutrients in food for absorption
- Antibodies - protection from foreign pathogens or clinical use
- Collagen - structure
- Transport Vessicle - transport
- Transcription Factors - gene regulation
- Aquaporins - transport of water across the membrane
Where does protein synthesis happen
ribosomes
How many amino acids are there
20
What is Monoclonal vs Polyclonal
M = all recognize same epitope
P = all recognize same antigen
What is a Noncompetitive inhibitor
binds away from active site, make active site less effective
What is a Competitive inhibitor
binds at active site
