Midterm #1 Vocabulary Flashcards
Cell
The smallest structural and functional unit of an organism
Data
Recorded observations
Quantitative : numerical measurements → graphs, tables
Qualitative : recorded descriptions
Dependent Variable
Variable whose value is measured during an experiment or other test to see whether it’s influenced by changes in another variable (independent variable)
in the termite experiment: did the termite follow the line?
Deoxyribonucleic Acid (DNA)
A nucleic acid molecule, usually a double-stranded helix, in which each polynucleotide strand consists of nucleotide monomers with a deoxyribose sugar and the nitrogenous bases adenine (A), guanine (G), thymine (T), and cytosine (C); capable of being replicated and determining the inherited structure of a cell’s proteins
Eukaryotic Cell
Type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles.
Organisms with eukaryotic cells are called Eukaryotes.
Evolution
Descent with modification; the idea that living species are descendants of ancestral species that were different from the present-day ones; also defined more narrowly as the change in genetic composition of a population from generation to generation.
Experiment
A scientific test, carried out under controlled conditions, involving manipulation of one or more factors in a system in order to see the effects of those changes
Gene
A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses).
Independent Variable
Variable whose value is manipulated or changed during and experiment or other test to reveal possible effects on another variable (the dependent variable).
What are the levels of biological organization?
“BEC POOT COM”
- Biosphere
- Ecosystems
- Communities
- Populations
- Organisms
- Organs and Organ Systems
- Tissues
- Cells
- Organelles
- Molecules
Natural Selection
Process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.
Prokaryotic Cell
Type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles.
DO NOT HAVE GOLGI APPARATUSES!
Organisms with prokaryotic cells are called Prokaryotes.
What are the steps in the scientific method?
- Observation
- Question
- Hypothesis
- Prediction
- Test the prediction
- Results
Atom
The smallest unit of matter that still retains the properties of an element
Proton
Positively charged subatomic particle
• Number of protons is the same as the atomic number
Electron
Negatively charged subatomic particle
Neutron
Electrically neutral subatomic particle
• The number of neutrons + the number of protons (the atomic number) = the mass number
Molecule
Atoms bonded together
Ion
An atom or group of atoms that has gained or lost one or more electrons, thus acquiring a charge
Valence Electron
An electron in the outermost electron shell
Electronegativity
The attraction of a particular atom for the electrons of a covalent bond
Nonpolar Covalent Bond
Type of covalent bond in which electrons are shared equally between 2 atoms of similar electronegativity
Polar Covalent Bond
Covalent bond between atoms that differ in electronegativity. The shared electrons are pulled closer to the more negative atom, making it slightly negative and the other atom slightly positive
Partial Charge
,
Hydrogen Bond
Type of weak chemical bond that’s formed when the slightly positive hydrogen atom of a polar covalent bond in one molecule is attracted to the slightly negative atom of a polar covalent bond in another molecule or in another region of the same molecule.
Solute
The substance that is dissolved
Solvent
Dissolving agent of a solution
Hydrophilic
Having an affinity for water
Hydrophobic
Having no affinity for water; tending to coalesce and form droplets in water
Organic Molecule
Molecule containing carbon (since carbon determines if something is organic)
Monomer
The repeating units that serve as the building blocks of a polymer
Polymer
A long molecule consisting of many similar or identical building blocks linked by covalent bonds
Functional Group
A specific configuration of atoms commonly attached to the carbon skeletons of organic molecules and involved in chemical reactions.
• There are 7 functional groups
Hydroxyl Group
(-OH) or (HO-)
• chemically reactive
• hydrophilic
→ polar due to electronegative oxygen
→ forms hydrogen bonds with water, helping dissolve compounds
→ compound name : alcohol (specific name usually ends in -ol)
Carboxyl Group
(-COOH)
• chemically reactive
• hydrophilic
→ acts as an acid (can donate H+) because the covalent bond between oxygen and hydrogen is so polar
→ compound name : carboxylic acid, or organic acid
Amino Group
(-NH2) • chemically reactive • hydrophilic → acts as a base; can pick up an H+ from the surrounding solution (water, in living organisms) → compound name : amine
Phosphate Group
(-OPO3 2-) • chemically reactive • hydrophilic → contributes negative charge (1- when inside a chain of phosphates; 2- when at the end). When attached, congers on a molecule the ability to react with water, releasing energy. → compound name : organic phosphate
Protein
A biologically functional molecule made up of one or more polypeptides (polymer of amino acids), each folded and coiled into a specific 3D structure
Amino Acid
An organic molecule with both an amino group (-NH2) and a carboxyl group (-COOH).
→ At the center is an asymmetric carbon atom (the alpha carbon), and its 4 different partners are an amino group, a carboxyl group, a hydrogen atom, and a variable group R (side chain)
Side Chain
Variable group attached to the asymmetric carbon in an amino acid. The physical and chemical properties of the side chain (R group) determines the unique characteristics of a particular amino acid, thus affecting its functional role in a polypeptide.
Peptide
A compound consisting of 2 or more amino acids linked in a chain. Bound by peptide bonds.
Carbohydrate
A sugar (monosaccharide) or one of its dimers (disaccharides) or polymers (polysaccharides)
Sugar
A monosaccharide
Monosaccharide
The simplest carbohydrate, active alone or serving s a monomer for disaccharides and polysaccharides. Also called simple sugars, monosaccharides have molecular formulas that are generally some multiple of CH2O.
→ most common monosaccharide is glucose (C6H12O6)
→ most names end in -ose
→ location of carbonyl group decided if its an aldose (glucose) or ketose (fructose)
→ trademark = carbonyl group (CO) and multiple hydroxyl groups (OH)
Polysaccharide
Polymers with a few hundred to a few thousand monosaccharides joined by glycosidic linkages
Nucleic Acid
Polymer made of monomers called nucleotides
Ribonucleic Acid (RNA)
Type of nucleic acid consisting of a polynucleotide made up of nucleotide monomers with a ribose sugar and the nitrogenous bases
• Usually single stranded
• Functions in protein synthesis, gene regulation, and as the genome of some viruses
Nucleotide
The building block of a nucleic acid, consisting of a 5-carbon sugar covalently bonded to a nitrogenous base and one or more phosphate groups
Lipid
Any of a group of large biological molecules, including fats, phospholipids, and steroids, that mix poorly, if at all, with water
Triglyceride (AKA Fat or Triglycerol)
A lipid consisting of 3 fatty acids linked to one glycerol molecule.
Steroid
Lipid characterized by a carbon skeleton consisting of 4 fused rings
Phospholipid
Lipid made up of glycerol joined to 2 fatty acids and a phosphate group. The hydrocarbon chains of the fatty acids act as nonpolar, hydrophobic tails, while the rest of the molecule acts as a polar, hydrophilic head.
→ form bilayers that function as biological membrane that shields their hydrophobic portions from water.
Amphipathic
Containing both a hydrophilic and a hydrophobic region
Hydrolysis
Chemical reaction that breaks bonds between 2 molecules by the addition of water; disassembles polymers into monomers