Module 2 (BIOLOGY) Flashcards
What are the key differences between prokaryotes and eukaryotes?
Nucleus: Absent in prokaryotes (nucleoid region), present in eukaryotes
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Transcription location: Cytoplasm in prokaryotes, nucleus in eukaryotes
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Translation location: Cytoplasm in both
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Cell membrane additions: Hopanoids in prokaryotes, sterols (cholesterol) in eukaryotes
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Size: Smaller in prokaryotes (1−2 micrometers), larger in eukaryotes (10−20 micrometers)
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Ratio of surface area to volume: High in prokaryotes, low in eukaryotes
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Internal organization: No organelles in prokaryotes (some contain plasmids), organelles present in eukaryotes
: What is the cell theory?
All organisms are made up of cells.
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The cell is the fundamental unit of life.
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Cells come from preexisting cells
Front: What are cell membranes composed of?
Lipids, proteins, and carbohydrates
What is the endomembrane system?
An interconnected system of membranes that includes the nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, vesicles, and plasma membrane
What is the role of mitochondria and chloroplasts?
They are organelles involved in harnessing energy and likely evolved from free-living prokaryotes.
What are phospholipids?
Amphipathic molecules with a hydrophilic head and hydrophobic tails that spontaneously form bilayers.
What are liposomes?
Enclosed bilayers spontaneously formed by phospholipids
What is the function of cholesterol in animal cell membranes?
It acts as a buffer to lessen the impact of temperature changes.
What are the three main types of proteins in the membrane and their functions?
Receptors: Allow the cell to receive signals from the environment.
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Enzymes: Catalyze chemical reactions.
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Transporters: Move ions or molecules across the membrane
What is the difference between integral and peripheral membrane proteins?
Integral membrane proteins: Permanently associated with cell membranes.
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Peripheral membrane proteins: Temporarily associated with the lipid bilayer or integral membrane proteins through weak noncovalent interactions
What is passive transport?
The simplest movement into and out of cells, which does not require energy
hat is the difference between simple diffusion and facilitated diffusion?
Simple diffusion is the movement of molecules across a membrane from an area of high concentration to an area of low concentration. Facilitated diffusion is similar, but the molecules move through a transport protein.
What is osmosis?
The diffusion of water across a semi-permeable membrane from a region of higher water concentration to a region of lower water concentration
What is turgor pressure?
The force exerted by water pressing against an object
What is the difference between passive and active transport?
Passive Transport: Movement of molecules across a membrane that does not require energy.
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Active Transport: Movement of molecules across a membrane that requires energy.
What is secondary active transport?
A type of active transport that uses the energy from the movement of one molecule down its concentration gradient to drive the movement of another molecule against its concentration gradient.
What is an example of primary active transport?
The sodium/potassium pump, which moves sodium and potassium ions in opposite directions across the cell membrane.
What are exocytosis and endocytosis?
Exocytosis: A vesicle fuses with the plasma membrane to deliver its contents outside the cell.
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Endocytosis: Material from outside the cell is brought into a vesicle
What are the functions of the Golgi apparatus?
Further modifies proteins and lipids produced in the ER.
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Sorts proteins and lipids as they move to their final destinations.
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Synthesizes the cell’s carbohydrates.
What is the function of lysosomes?
They degrade proteins, nucleic acids, lipids, and complex carbohydrates
What are the two main types of metabolism?
Catabolism: The breakdown of complex molecules into simpler ones, releasing energy.
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Anabolism: The synthesis of complex molecules from simpler ones, requiring energy.
What is an enzyme?
A biological catalyst that speeds up the rate of a chemical reaction without being consumed in the process.
What is cellular respiration?
The process by which cells convert glucose and oxygen into ATP, the cell’s primary energy currency.
What is photosynthesis?
The process by which plants and other organisms use sunlight to synthesize glucose from carbon dioxide and water.
What are the main phases of the cell cycle?
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Interphase: The cell grows and replicates its DNA.
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Mitosis (M phase): The replicated chromosomes are separated and the cell divides into two daughter cells.
Flashcard 27
What are some key characteristics of fungal cells?
Eukaryotic cells
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Have a cell wall made of chitin
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Heterotrophic - they obtain nutrients by absorbing organic matter from their environment
Front: What is metabolism?
Back: Metabolism is the set of biochemical reactions that transform biomolecules and transfers energy.
Front: What are the first and second laws of thermodynamics?
Back:
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The first law of thermodynamics states that energy cannot be created or destroyed, only transferred or transformed.
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The second law of thermodynamics states that the entropy of a closed system always increases over time.
What is entropy?
Back: Entropy is a measure of disorder or randomness.
Front: What is ATP?
Back: ATP (adenosine triphosphate) is a molecule that stores and releases energy for cellular processes.
Front: Why is ATP called the “currency of energy”?
Back: The chemical energy of ATP is held in the bonds connecting the phosphate groups. Breaking these bonds releases energy that can be used by the cell.
Front: What is chemical energy?
Back: Chemical energy is a form of potential energy held in the chemical bonds between pairs of atoms in a molecule.
Front: What are the requirements of a cell?
Back:
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A membrane to separate the inside of the cell from the outside
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A way to encode and transmit information
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Energy
Front: What is the microbiome?
Back: The microbiome is a collection of microbes that are both helpful and potentially harmful. It consists of mutualists, commensals, and pathogens
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Front: Where does the energy come from to support human activities?
Back: The energy to support human activities comes from the food we eat. This includes glucose, fructose, proteins, lipids, sucrose, and polysaccharides. These molecules are broken down by the body to release energy.
Front: What is catabolism?
Back: Catabolism is the breakdown of complex molecules into simpler ones, releasing energy.
Front: What is anabolism?
Back: Anabolism is the synthesis of complex molecules from simpler ones, requiring energy.
Front: What is the main difference between catabolism and anabolism?
Back: Catabolism involves the breakdown of complex molecules into simpler ones, releasing energy, while anabolism refers to the synthesis of complex molecules from simpler ones, requiring energy.4
Front: List the key biomolecules that contribute to energy production for human activities.
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Glucose78
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Fructose78
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Proteins78
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Lipids78
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Sucrose8
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Polysaccharides8
Front: Identify the primary source of energy for human activities.
Back: The food we consume provides the primary source of energy for human activities.78
Front: What type of microbes are present in smaller numbers within the human microbiome and what is their effect?
Back: Pathogens, microbes that can promote diseases, are present in smaller numbers within the human microbiome.7
Front: Characterize the majority of microbes within the human microbiome.
Back: Most microbes within the human microbiome exist as either mutualists, providing benefits to both the host and themselves, or commensals, neither harming nor benefiting the host.7
Front: Describe the cellular composition of the microbiome associated with the human body.
Back: The microbiome associated with the human body contains a greater number of microbial cells than the total number of human cells.7
Front: What is the composition of the microbiome?
Back: The microbiome comprises microbes that can be both beneficial and potentially detrimental to the host.7
Front: Define entropy.
Back: Entropy serves as a measure of disorder or randomness within a system. A system with high entropy exhibits greater disorder than a system with low entropy.67
Front: What is the focus of the second law of thermodynamics?
Back: The second law of thermodynamics deals with energy transformation and asserts that the entropy of a closed system inevitably increases over time.6
Front: Explain the first law of thermodynamics.
Back: The first law of thermodynamics centers on the principle of energy conservation, stating that energy cannot be created or destroyed, but only transferred or transformed.6
Front: Where is the chemical energy of ATP stored?
Back: The chemical energy of ATP is stored within the bonds connecting the phosphate groups.5
Front: How do cells manage the energy they possess?
Back: Instead of utilizing all their energy at once, cells package energy into a readily accessible chemical form, primarily ATP.5
Front: Explain the relationship between strong bonds and potential energy in molecules.
Back: Strong bonds possess less potential energy compared to weak bonds.5
Front: Define metabolism.
Back: Metabolism encompasses all the biochemical reactions that occur within an organism to transform biomolecules and transfer energy.34
Front: Provide two examples of how ATP is utilized in cellular activities.
Back:
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The sodium/potassium pump, an example of an antiporter.2
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Muscle contraction.2
Front: Where is the highest energy bond located in Adenosine Triphosphate (ATP)?
Back: The highest energy bond is located at the outer layer, linking the phosphate group.2
Front: Besides a phospholipid bilayer and associated proteins, what else can be found in the plasma membranes of human liver cells?
Back: Cholesterol. Cholesterol is a component of animal cell membranes.1
Front: What is Gibbs free energy?
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Back: Gibbs free energy (ΔG) is the amount of energy in a system available to do work.
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Front: Define endergonic reactions.
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Back: Endergonic reactions have a positive ΔG, require an input of energy, and are non-spontaneous.
Front: What is the formula for Gibbs free energy?
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Back: ΔG = ΔH − TΔS, where ΔH is the enthalpy change, T is the absolute temperature, and ΔS is the entropy change.
Front: Define exergonic reactions.
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Back: Exergonic reactions have a negative ΔG, release energy, and are spontaneous.
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Front: Describe energetic coupling.
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Back: Energetic coupling is a process where a spontaneous reaction (negative ΔG) drives a non-spontaneous reaction (positive ΔG
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Front: What is ATP’s role in energetic coupling?
Back: ATP acts as the energy provider in energetic coupling.
Front: What is activation energy (EA)?
Back: Activation energy is the minimum amount of energy required to start a chemical reaction.
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Front: How do enzymes affect the rate of a reaction?
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Back: Enzymes are protein catalysts that increase the rate of biochemical reactions by lowering the activation energy.
Front: What is the enzyme-substrate complex?
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Back: The enzyme-substrate complex (ES) is formed when a substrate (S) binds to the active site of an enzyme (E).
Card 10
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Front: What happens at the enzyme’s active site?
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Back: The active site binds to the substrate and facilitates its conversion into the product, lowering the activation energy.
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Front: How is enzyme shape related to its function?
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Back: The specific shape of the enzyme’s active site determines which substrates it can bind and the reaction it catalyzes.
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Front: Explain enzyme specificity.
Back: Enzyme specificity refers to the selective binding of an enzyme to a particular substrate due to the complementary shapes of the active site and the substrate
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Front: What are enzyme inhibitors?
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Back: Enzyme inhibitors are molecules that bind to enzymes and decrease their activity
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Front: Differentiate between reversible and irreversible enzyme inhibitors.
Back: Reversible inhibitors bind to the enzyme through weak bonds and can dissociate, while irreversible inhibitors form covalent bonds and permanently inactivate the enzyme
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Front: What are allosteric enzymes?
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Back: Allosteric enzymes are enzymes that are activated or inhibited when a molecule binds to a site other than the active site, changing the enzyme’s shape.
Front: What are the core concepts of chemical reactions?
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Chemical reactions involve the breaking and forming of bonds.
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Energetic coupling: Spontaneous reactions drive non-spontaneous reactions.
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Enzymes are protein catalysts that can increase the rate of biochemical reactions.
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Allosteric enzymes are activated or inhibited when binding to another molecule changes their shape.
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Front: What are free radicals?
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Back: Free radicals are unstable molecules due to the loss of electrons and contribute to the aging process.
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Front: What are anabolic pathways?
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Back: Anabolic pathways build larger molecules from smaller units, consuming energy (endergonic).
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Front: What are catabolic pathways?
Back: Catabolic pathways break down molecules into smaller units, releasing energy (exergonic) and producing ATP.
Front: How do glycolysis and the citric acid cycle function?
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Back: These pathways break down glucose into smaller molecules, releasing energy. They are catabolic pathways and take place in both animal and plant cells.
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Front: What is the function of RNA polymerase II?
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Back: RNA polymerase II is a vital enzyme in the synthesis of messenger RNA (mRNA), microRNA, and small nuclear RNA (snRNA).
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Front: What is α-Amanitin?
Back: α-Amanitin is a selective inhibitor of RNA polymerase II, found in some toxic mushrooms.
Front: Why are some mushrooms toxic to humans?
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Back: Some mushrooms, like Amanita phalloides, contain toxins such as amatoxins that inhibit RNA polymerase II, disrupting vital cellular processes.
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Front: What are mycotoxins?
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Back: Mycotoxins are toxic secondary metabolites produced by fungi. Examples include aflatoxins, amatoxins, citrinin, and ergot alkaloids
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Front: Name some fungi that produce mycotoxins.
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Back: Examples include Aspergillus, Penicillium, Amanita, Lepiota, Galerina, and Fusarium species.