Exam 1 Learning Objectives Flashcards
Organism being alive means:
It is a life-form: a living entity made up of cells, uses energy
Cytoplasm
All of the contents of a cell inside the membrane (excluding the nucleus in eukaryotes)
Cell theory
All cells come from pre-existing cells
Organisms’ 2 fundamental nutritional needs
Chemical energy (ATP) and molecules that can be used as building blocks for synthesis of DNA, RNA, proteins, cell membrane, etc.
Characteristics of an organism
Cells, Replication, Information, Energy, Evolution
Central Dogma
Describes the flow of information in cells. Put simply, DNA codes for RNA, which codes for proteins
Energy
The capacity to do work or supply heat. This capacity exists in one of two ways—as a stored potential or as an active motion.
Entropy
The amount of disorder in a system (or the surrounding environment). Increases in the system when the products of a chemical reaction are less ordered than the reactant molecules.
Monosaccharides are typically found with ____?
3, 5, or 6 carbons.
Forms of glucose
α-glucose and β-glucose. β is more common because it is slightly more stable than α.
Polysaccharides
Made from condensation reactions bringing together monosaccharides.
Uses: energy sources, structural roles like insect exoskeletons & cell walls, or cell identification & recognition
Glycolipid
Any lipid molecule that is covalently bonded to one of more carbohydrates
Glycoprotein
Any protein with one or more covalently bonded carbohydrates, typically oligosaccharides
Plasma membrane allow for _____?
Exchange of materials
The nucleus is the area of ____?
Maintenance and replication of the genome, distribution of genetic material (transcription DNA -> RNA), and ribosomal production (ribosomal subunit assembly).
Cytosol
The fluid portion of the cytoplasm, excluding the contents of membrane-enclosed organelles. Only a fraction of the total cell volume.
.
Organelle
A compartment inside the cell – often bounded by a membrane – that contains enzymes or structures specialized for a particular function
Fats
Also called triglycerides, primary role is energy storage
Phospholipids
Class of lipids having a hydrophilic head (with a phosphate group) and a hydrophobic tail (consisting of 2 hydrocarbon chains), crucial components of the plasma membrane.
- ____ with fatty acid tails are found in the domains Bacteria and Eukarya
- ____ with isoprenoid tails are found in the domain Archaea
Lipids
Any organic substance that does not dissolve in water but dissolves well in nonpolar organic solvents. ____ include fatty acids, fats, oils, waxes, steroids, and phospholipids.
Types of lipids
Steroids (bulky, 4-ring structure), Fats (nonpolar molecules, 3 fatty acids linked to glycerol), Phospholipids (a glycerol that is linked to a phosphate group and 2 hydrocarbon chains)
Lipid bilayers
Basic structural element/foundation of all cellular membranes. Hydrophilic heads interact with water, hydrophobic tails interact with one another
Diffusion
The spontaneous movement of molecules and ions
Concentration Gradient
The difference across space (such as across a membrane) in the concentration of a dissolved substance
Osmosis
Diffusion of water across a selectively permeable membrane from a region of higher water concentration (lower solute concentration) to a region of lower water concentration (higher solute concentration. Often observed when the solute is not able to pass through the membrane.
Channel Proteins
Form pores in the membrane that may have highly regulated closed and open conformations and facilitate the diffusion of water or specific solutes into and out of the cell.
Carrier Proteins
Undergo conformational changes that facilitate the diffusion of specific molecules into and out of the cell.
Nucleotides
A molecule consisting of a 5-C sugar (ribose or deoxyribose), one or more phosphate groups, and one of the several N-containing bases. ____ polymerize via condensation reactions.
Ribonucelotides
Monomers of RNA
Deoxyribonucleotides
Monomers of DNA
Basic amino acids
+ charged
Acidic amino acids
- charged
Acid
Proton donor
Primary Structure
sequence of amino acids in a protein. All proteins have a unique ____
Secondary Structure
α-helices and β-pleaded-sheets that are formed by H-bonding between backbone atoms located near each other in a polypeptide chain.
Tertiary Structure
Achieved when a protein folds into a compact, 3D shape stabilized by interactions between side-chain R groups of amino acids.
Quaternary structure
Result of 2 or more protein subunits assembling to form a larger, biologically active protein complex.
Prions
Proteins that can be induced to fold into infections, disease-causing agents. Same primary structure, but the shape is radically different.
Proteins are crucial to
Catalysis, structure, movement, signaling, transport, and defense of cells.
