What is metabolism?

• buildup and breakdown of nutrients within a cell

What is the difference between catabolism and anabolism?

• Catabolism = breaking down complex molecules, aka taking large molecules and making them smaller

• Anabolism = taking smaller molecules as building blocks to create bigger ones

What is a metabolic pathway?

• sequences of chemical reactions

Define the following terms: collision theory, activation energy, active site, substrate, catalyst and enzyme:

• Collision Theory = states that chemical reactions occur when atoms, ions, and molecules collide

• Activation Energy = the energy required for a chemical reaction to occur

• Active Site = a region on an enzyme where substrates bind and undergo a chemical reaction. It plays a crucial role in catalyzing the conversion of substrates into products.

• Substrate = lower activation energy

• Catalyst = speed up chemical reactions without being altered

What are cofactors and coenzymes?

• Cofactor = nonprotein component

• Coenzyme = organic cofactor

What are some factors that affect enzymes?

• temperature

• pH

• substrate concentration

• inhibitors

What is the difference between competitive and noncompetitive inhibition?

• Competitive Inhibitions = fill the active site of an enzyme and compete w/ substrate

• Noncompetitive Inhibitions = the inhibitor is not competing for the active site, binds to the allosteric site

What are some differences between fermentation and respiration?

• Fermentation = when no oxygen is present,

• Respiration = if oxygen is present, consists of the Krebs cycle electron transport

Using the PowerPoint table, be able to summarize the following for glycolysis, fermentation, Krebs cycle and Electron transport: location, oxygen conditions, starting material, end product and energy yield:

• write out to study

What are beta oxidation and deamination in the breakdown of fats and proteins?

• beta-oxidation = breaking down fatty acids are into acetyl groups for energy

• deamination = Removal of amino group from amino acids during protein breakdown.

What is the difference between light dependent reactions and light independent reactions?

• Light dependent = conversion of light energy into chemical energy (ATP /NADPH)

• Light independent = ATP and NADPH are used to reduce CO2 to sugar (carbon fixation) via the Calvin-Benson cycle

When photosystem I and II are both present, which one occurs first?

• Photosystem 2

Understand the basics of the Calvin-Benson cycle:

• Circular cycle where carbon dioxide is converted to glucose

• Calvin-Benson cycle is the light-independent reactions of photosynthesis

• Takes place in the stroma of chloroplasts

• Key steps: carbon fixation, reduction, regeneration of RuBP

• Rubisco enzyme catalyzes the first step

• Produces G3P, a precursor for glucose production

Understand how the physical requirements of temperature, pH and osmotic pressure affect growth:

• are critical factors affecting microbial growth. Each microorganism has an optimal range for these parameters, and deviations can inhibit growth or even lead to cell death. Temperature influences enzyme activity, pH affects protein structure, and osmotic pressure impacts water balance.

Understand how the chemical requirement of oxygen affects growth

• Oxygen is essential for cellular respiration, a process that generates ATP for energy. Without oxygen, cells cannot efficiently produce energy, leading to impaired growth and metabolism in organisms.

Differentiate the following terms: psychrophiles, mesophiles and thermophiles

• Psychrophiles: Organisms that thrive in cold temperatures below 20°C. (cold-loving)

• Mesophiles: Organisms that grow best in moderate temperatures around 20-45°C. (moderate-temp loving)

• Thermophiles: Organisms that flourish in high temperatures above 45°C. (heat-loving)

Differentiate the following terms: acidophiles, neutrophiles and alkaliphiles

• Acidophiles: thrive in acidic environments (pH < 3)

• Neutrophiles: grow best in neutral pH environments (pH 5-8)

• Alkaliphiles: prefer alkaline conditions/ high pH environments (pH > 9)

What is a halophile?

• an organism that thrives in high salt concentrations, typically found in environments like salt lakes or salt mines.

Differentiate the following terms: aerobes, anaerobes and facultative anaerobes

• Aerobes: Organisms that require oxygen for growth.

• Anaerobes: Organisms that can survive without oxygen.

• Facultative Anaerobes: Organisms that can switch between aerobic and anaerobic metabolism. (can survive with or without oxygen)

Which type of lab handles the deadliest microbes like Ebola and smallpox?

• Biosafety Level 4 (BSL-4) labs

Differentiate the following terms: selective medium, differential medium and enrichment medium (aka media)

• Selective medium: Promotes the growth of specific organisms while inhibiting others.

• Differential medium: Allows distinguishing between different types of organisms based on their growth characteristics.

• Enrichment medium: Stimulates the growth of specific organisms by providing specific nutrients.

How do most bacteria reproduce?

• through binary fission, a process where a single cell divides into two identical daughter cells.

Understand the basics of the following counting procedures: direct count, serial dilution and plate count, MPN, filtration and turbidity

• Direct Count: Counting cells using a microscope.

• Serial Dilution and Plate Count: Diluting samples to count viable cells. (most used method)

• MPN: Most Probable Number method for estimating cell concentration.

• Filtration: Filtering samples to concentrate cells.

• Turbidity: Measuring cloudiness to estimate cell density.

What is the difference between sterilization and sanitization?

• Sterilization = removing and or killing all microbial life

• Sanitization - only lower microbial counts to a safe level (mainly things like eating utensils)

What is the difference between a disinfectant and an antiseptic?

• Disinfectant = destroys harmful microorganisms (only used on inanimate objects)

• Antiseptic = destroys harmful microorganisms on living tissue (rubbing alcohol, iodine, hydrogen peroxide)

What is the difference between a chemical that is bacteriocidal vs bacteriostatic?

• Bacteriocidal = kills bacteria

• Bacteriostatic = doesn’t kill bacteria, only inhibits it

Which of the following works better for killing microbes: moist heat or dry heat?

• moist heat

What are some alternatives to reducing microbes in heat sensitive materials?

• pasteurization or filtration

What is Pasteurization?

• reduces spoilage organisms and pathogens

Understand the basics of the following methods of controlling microbes: filter sterilization, refrigeration, freezing, lyophilization, desiccation, osmotic pressure, UV radiation

• Filter sterilization: Removes microbes by passing through a filter.

• Refrigeration & Freezing: Slows microbial growth by lowering temperature.

• Lyophilization: Freeze-drying to preserve microbes.

• Desiccation: Drying out microbes to inhibit growth.

• Osmotic pressure: Using high salt/sugar to dehydrate microbes.

• UV radiation: Damages microbial DNA to prevent reproduction.

Why is phenol important?

• Phenol is important due to its use in the production of various chemicals, disinfectants, and pharmaceuticals. It is also used in the synthesis of plastics, resins, and as an antiseptic in medicine.

What is a halogen?

• column 7 of the periodic table

• group of non-metal elements in the periodic table (fluorine, chlorine, bromine, iodine, and astatine. They have seven electrons in their outer shell, making them highly reactive.

What is a heavy metal?

• has a heavy atomic mass, toxic to humans (mercury and lead)

What is a tincture?

• solution in aqueous alcohol

What makes alcohol a little unusual as an antiseptic?

• because of it being a drying agent

What type of chemical is hydrogen peroxide and what type of bacteria does it work well against?

• Chemical Type: Hydrogen peroxide is a chemical compound with the formula H2O2, classified as a peroxide.

• Bacteria: Hydrogen peroxide is effective against a wide range of bacteria, including Staphylococcus, Streptococcus, and E. coli

What is genetics?

• the study of genes, how they carry information, how information is expressed, and how genes are replicated

What is the difference between a gene and a chromosome?

• Gene = segments of DNA that encode functional products, usually proteins

• Chromosomes = structures containing DNA that physically carry hereditary information; the chromosomes contain genes

What is the difference between genotype and phenotype?

• Genotype: Genetic makeup of an organism.

• Phenotype: Observable traits of an organism influenced by genotype and environment.

What are several differences between RNA and DNA?

• Structure = RNA is single-stranded, while DNA is double-stranded.

• Sugar = RNA contains ribose sugar, DNA contains deoxyribose sugar.

• Bases = RNA has uracil (U) as a base instead of thymine (T) found in DNA.

• Function = RNA is involved in protein synthesis, DNA stores genetic information.

• Location = RNA is found in the cytoplasm and nucleus, DNA is mainly in the nucleus.

Understand what is meant when we say polymerases and ribosomes work in a 5’ to 3’ direction:

• refers to the direction in which they synthesize nucleic acids. They add nucleotides to the 3’ end of the growing strand, moving towards the 5’ end.

Understand the processes of transcription, translation and replication:

• Transcription = the process of copying DNA into mRNA

• Translation = converting mRNA into proteins

• Replication = duplicating DNA.

Understand the basics of a replication fork:

• A replication fork is a structure formed during DNA replication where the DNA double helix is unwound and new DNA strands are synthesized. It involves the leading and lagging strands, DNA polymerase, primase, helicase, and other enzymes.

What is the difference between the leading and lagging strand?

• Leading strand = synthesized continuously in the 5' to 3' direction

• Lagging strand = synthesized discontinuously in Okazaki fragments.

What are Okazaki fragments?

• short, newly synthesized DNA fragments formed on the lagging strand during DNA replication. They are created discontinuously and later joined together by DNA ligase to form a complete strand.

When are RNA primers needed?

• RNA primers are needed in DNA replication to provide a starting point for DNA polymerase to begin synthesis. They are essential for initiating the replication process.

Know how to read the genetic code or codon chart:

• To read the genetic code or codon chart, start from the middle of the chart and match the mRNA codon to the corresponding amino acid. The chart shows all possible combinations of three nucleotides (codons) and their corresponding amino acids.

What are the three different types of RNA and their functions?

• mRNA (messenger RNA) = Carries genetic information from DNA to ribosomes for protein synthesis.

• rRNA (ribosomal RNA) = Forms the structure of ribosomes and helps in protein synthesis.

• tRNA (transfer RNA) = Transfers amino acids to the ribosome during protein synthesis.

What are codons and anticodons?

• Codons = sequences of three nucleotides on mRNA that code for specific amino acids during protein synthesis

• Anticodons = complementary sequences on tRNA that bind to codons to ensure the correct amino acid is added to the growing polypeptide chain.

What is a polysome or polyribosome?

• a cluster of ribosomes translating the same mRNA simultaneously, creating multiple copies of a protein. This process enhances efficiency in protein synthesis.

What is a mutation?

• a change in the DNA sequence of an organism. It can lead to variations in traits and can be caused by various factors like radiation or errors in DNA replication.

Differentiate the following terms: transformation, transduction and conjugation

• Transformation = DNA uptake by bacteria from the environment.

• Transduction = DNA transfer via bacteriophages.

• Conjugation = DNA transfer through direct cell-to-cell contact.