Foundations of Biochem Flashcards
A high degree of chemical complexity and microscopic organization; systems for extracting, transforming, and using energy from the environment; defined functions for every component and regulated interactions among them; mechanisms for sensing and responding to alterations in surroundings; a capacity for precise self-replication and self-assembly; capacity to change over time by gradual evolution
The distinguishing features of living organisms
The periphery of the cell, separating its contents from the surroundings
Plasma membrane
Allows the passage of certain ions and molecules
Transport proteins
Transmit signals into the cell
Receptor proteins
The internal volume enclosed by the plasma membrane, composed of the cytosol and a variety of suspended particles with specific functions
Cytoplasm
The site of protein synthesis
Ribosomes
Oxidizes fatty acids
Peroxisomes
Supports the cell and aids in movement of organelles. Composed of actin filaments, microtubules, and intermediate filaments
Cytoskeleton
Degrades intracellular debris using digestive enzymes
Lysosomes
Shuttles lipids and proteins between ER, Golgi, and plasma membrane
Transport vesicles
Processes lipids and membrane proteins, packages, and targets proteins to other organelles or for export
Golgi apparatus
Site of lipid synthesis and drug metabolism
Smooth Endoplasmic Reticulum (ER)
Segregates chromatin (DNA and protein) from the cytoplasm
Nuclear envelope
Contains the genes (chromatin)
Nucleus
Site of ribosomal RNA synthesis
Nucleolus
Site of much of protein synthesis
Rough Endoplasmic Reticulum (ER)
Oxidizes fuels to produce ATP. Site of most energy extracting reactions of the cell
Mitochondria
Harvests sunlight, produces ATP and carbohydrates
Chloroplast
Temporarily stores carbohydrate products of photosynthesis
Starch granule
Site of light-driven ATP synthesis
Thylakoids
Provides shape and rigidity; protects cell from osmotic swelling
Cell wall
Degrades and recycles macromolecules, stores metabolites
Vacuole
Provides path between two plant cells
Plasmodesmata
Contains enzymes of the glyoxylate cycle
Glyoxysome
Transport out of the cell
Exocytosis
Transport into the cell
Endocytosis
Bacteria that are colored by Gram’s stain. Lacks an outer membrane. Contain a thick layer of peptidoglycan outside of the plasma membrane
Gram positive bacteria
Bacteria that is not colored by Gram’s stain. Has an additional outer membrane composed of a lipid bilayer
Gram negative bacteria
Single, circular molecule of DNA
Plasmid
Bacteria, Archaea, and Eukarya
The three distinct domains of life
Inhabits soils, surface waters, and tissues of other living or decaying organisms
Bacteria
Inhabits extreme environments like salt lakes, hot springs, highly acidic bogs, and the ocean depths
Archaea
Which are eukaryotes more closely related to, bacteria or archaea?
Archaea
Environments with plentiful oxygen
Aerobic
Environments devoid of oxygen
Anaerobic
Organisms that die when exposed to oxygen
Obligate anaerobes
Organisms that are able to live with or without oxygen
Facultative anaerobes
Organisms that trap and use sunlight as energy
Phototrophs
Organisms that derive their energy from oxidation of chemical fuel
Chemotrophs
Organisms that synthesize their biomolecules directly from carbon dioxide
Autotrophs
Organisms that require some preformed organic nutrients made by other organisms
Heterotrophs
Hydrogen, oxygen, nitrogen, and carbon
The 4 most abundant elements in living organisms
Shorter polymers
Oligomers
Long polymers of amino acids that constitute the largest fraction (besides water) of the cell
Proteins
Nucleic acids that are polymers of nucleotides. Stores and transmits genetic information
DNA and RNA
The entire sequence of a cell’s DNA
The genome
Polymers of simple sugars like glucose
Polysaccharides
Energy-rich fuel stores, rigid structural components of cell walls, and extracellular recognition elements that bind to proteins on other cells
Three major functions of polysaccharides
All of a cell’s carbohydrate-containing molecules
Glycome
Water insoluble hydrocarbon derivatives. Serve as structural components of membranes, energy-rich fuel stores, pigments, and intracellular signals
Lipids
Carbon containing molecules that have the same chemical bonds and same chemical formula but differ configuration
Stereoisomers
Stereoisomers that are mirror images of each other
Enantiomers
Stereoisomers that are not mirror images of each other
Diastereomers
In living organisms, chiral molecules are usually present in how many of their chiral forms?
One
All the constituent reactants and products, the solvent that contains them, and the immediate atmosphere
A system
The system and its surroundings
A universe
When the system exchanges neither energy nor matter with its surroundings it is
Isolated
When the system exchanges energy but not matter with its surrounding it is
Closed
When it exchanges both energy and matter with its surroundings; All living organisms
An open system
The randomness or disorder of the components of a chemical system
Entropy
The amount of energy available to do work
Free-energy
Energy requiring reactions. Have a positive delta G (free energy)
Endergonic
Reactions that do not require an energy input. Have a negative delta G (free energy)
Exergonic
Energy pathway that degrades organic nutrients. Breaks things down and are exergonic
Catabolic reactions
Uses energy created from catabolic reactions. Builds things up, endergonic
Anabolic reactions
