Biology Basics (Units 1-5) - Flashcards from Summer Reading Guide Notes

A comprehensive set of concept-focused flashcards covering basic biology concepts from the notes (units 1-5).

What is biology?

The study of life.

What is the smallest unit of an element?

Atom.

What is a molecule?

Union of two or more atoms of the same or different elements.

What is a cell?

The structural and functional unit of all living organisms.

What is tissue?

A group of cells with a common structure and function.

What is an organ?

Composed of tissues functioning together for a specific task.

What is an organ system?

Comprised of several organs working together.

What is an organism?

An individual; complex organisms contain organ systems.

What is a species?

A group of similar, interbreeding organisms.

What is a population?

Organisms of the same species in a particular area.

What is a community?

Interacting populations in a particular area.

What is an ecosystem?

A community plus the physical environment.

What is the biosphere?

Regions of Earth inhabited by living organisms.

What are the three tenets of cell theory?

All organisms are composed of cells; cells are the basic units of structure and function; cells come only from pre-existing cells.

What are the two types of cells?

Prokaryotic and Eukaryotic cells.

What is a prokaryotic cell characterized by?

Lacks a membrane-bound nucleus.

What is a eukaryotic cell characterized by?

Possesses a membrane-bound nucleus.

What is an ecosystem? (definition)

A community plus the physical environment.

What are the major processes of an ecosystem?

Cycling of matter (water, nitrogen, carbon, etc.) and energy flow.

Why are organisms considered open systems?

Because they exchange energy with the environment.

What is positive feedback?

Proliferates the processes in a system.

What is negative feedback?

Brings a system back to homeostasis.

What is the combined importance of positive and negative feedback?

Positive amplifies processes; negative maintains stability (homeostasis).

What is evolution?

The study of diversity and how life came to be (change over time).

What is intelligent design?

The idea that the world’s design is not random (not from the book).

What are the three domains of life?

Bacteria, Archaea, and Eukarya.

Why were domains developed?

To separate major types of life based on fundamental differences.

What unites the diversity of life?

All require energy to survive and all have cells.

What is science?

The study of the structure and behavior of the physical world through observation and testing.

What is a hypothesis?

A possible explanation of a phenomenon that must be supported by observations.

What is a theory?

Broad concepts that join together and are well supported by multiple tested hypotheses.

What is a law in science?

A theory that has never been disproven.

What is discovery-based science?

Inductive science that aims to explore, observe, and discover.

What is induction?

Using related observations to arrive at a general conclusion.

What is hypothetico-deductive science?

Hypothesis-based science that begins with a question and testable solution.

What are the basic steps of the scientific method?

Observation, question, hypothesis, prediction, experiment, result.

In a controlled experiment, what is the dependent variable?

A factor that relies on the change in the independent variable.

In a controlled experiment, what is the independent variable?

The factor that you change in the experiment.

What are constants/controls in an experiment?

Factors that stay the same throughout the experiment.

What is a control group?

The group that has nothing added to it; no outside factors affect it.

What is an experimental group?

The group that receives the change being tested (the independent variable).

What are the eight elements that make up the majority of our bodies?

Carbon, Hydrogen, Oxygen, Sulfur, Nitrogen, Phosphorus, Calcium, Potassium.

Describe the structure of an atom and the location/charge of subatomic particles.

Nucleus contains protons (+) and neutrons (neutral); electrons (-) orbit the nucleus.

What is an isotope?

An element variant with the same number of protons but different neutrons.

What are common applications of isotopes?

Medicine, industrial processes, commercial production, etc.

How is energy transferred through atoms?

Movement of electrons through the valence shells.

Which electrons are most important for chemical bonding?

Valence electrons.

What is the difference between a molecule and a compound?

A molecule is two or more atoms; a compound has two or more different types of atoms.

How does a covalent bond hold atoms together?

By sharing electrons between atoms.

What is the difference between polar and non-polar covalent bonds?

Non-polar covalent bonds have evenly distributed charge; polar covalent bonds have uneven charge distribution.

What is an ion and what are the two types?

An ion is an atom or molecule with a net electrical charge; cations are positive and anions are negative.

What is a hydrogen bond?

A weak attractive interaction between a hydrogen atom and an electronegative atom.

What are Van der Waals interactions?

Weak interactions due to transient charges between molecules.

What is the difference between cohesion and adhesion?

Cohesion: water molecules cling to each other; adhesion: water sticks to polar surfaces.

What is the difference between a solute and a solvent?

Solute: substance dissolved; solvent: substance doing the dissolving.

What is the difference between hydrophilic and hydrophobic molecules?

Hydrophilic: water-loving; hydrophobic: water-fearing; not easily dissolved in water.

What are the unique characteristics of water that are important to biology?

High heat capacity, ice floats, solvent properties, cohesion and adhesion, and water polarity.

How can water dissociate, and what are the products?

Water can dissociate into H+ (hydrogen) and OH− (hydroxide) ions.

What makes an acid an acid and a base a base? How many differences are there between them?

Acids have high H+; bases have high OH− and low H+. Key differences include pH, ion concentrations, and taste/feel in common contexts.

Why is carbon so well-suited as a building block of biology?

Carbon has four valence electrons, enabling versatile covalent bonding; it can form double/triple bonds and bond with many elements, especially hydrogen.

What are functional groups? Name six and a brief characteristic for each.

Groups of bonded atoms with characteristic reactivity: Hydroxyl (polar, H-bonds); Carbonyl (polar, in sugars); Carboxyl (polar and acidic); Amino (polar, basic, forms H-bonds); Sulfhydryl (forms disulfide bonds); Phosphate (polar, acidic, in phospholipids and nucleotides).

What is a polymer and what is a monomer?

Monomers are subunits that join to form polymers (carbohydrates, proteins, nucleic acids, etc.).

Describe a condensation/dehydration reaction.

Two monomers join to form a larger molecule with the release of water (-removal of -OH and H+).

Describe hydrolysis.

A water molecule is added, breaking a larger molecule into smaller units (H+ to one monomer, OH− to the other).

What are carbohydrates? Include monomers and functions.

Carbohydrates are energy-rich biomolecules; monomers are monosaccharides (glucose); polymers include starch, glycogen, cellulose; functions: energy storage and structural roles.

What is the difference between starch, glycogen, and cellulose?

Starch stores glucose in plants (amylose and amylopectin); glycogen stores glucose in animals (highly branched); cellulose is a structural polysaccharide in plants (indigestible by most animals).

What are lipids? Their monomers and function?

Lipids are fats/triglycerides, insoluble in water; monomers are fatty acids and glycerol; functions include energy storage, insulation, padding, and hormones.

What is the biological significance of phospholipids, steroids, and cholesterol?

Phospholipids: main component of cell membranes; Steroids: components of membranes and hormones; Cholesterol: membrane stability and precursor to other steroids.

What are proteins? Their monomers and two major functions?

Proteins are polymers of amino acids; monomers are amino acids; major functions include structural roles and enzymes (catalysis).

Describe the structure of amino acids and the role of the R-group.

Amino acids have an amino group, a carboxyl group, a hydrogen, and a variable R-group; the R-group determines the amino acid’s properties (polar, nonpolar, etc.).

Differentiate primary, secondary, tertiary, and quaternary protein structure.

Primary: linear sequence; Secondary: alpha-helix or beta-pleated sheet; Tertiary: 3D folding; Quaternary: multiple polypeptides interacting.

What is metabolism? Differentiate between anabolism and catabolism.

Metabolism = all chemical reactions in an organism; Anabolism builds up molecules using energy; Catabolism breaks down molecules to release energy.

What is the first law of thermodynamics? Second law?

1st law: energy cannot be created or destroyed, only converted; 2nd law: energy transformations increase entropy and use less usable energy.

What is the difference between exergonic and endergonic reactions?

Exergonic: release energy; Endergonic: require an input of energy to occur.

Describe the enzyme/substrate complex.

A complex formed when a substrate binds to an enzyme’s active site; the enzyme acts as a catalyst to speed the reaction.

What factors affect the function of enzymes?

Temperature, pH, substrate and enzyme concentration, and cofactors or inhibitors.

What is diffusion? Osmosis?

Diffusion: spontaneous movement down a concentration gradient; Osmosis: diffusion of water across a selectively permeable membrane.

What is facilitated diffusion and what enables it?

A passive transport down a concentration gradient aided by a transport protein.

Describe the following active transports: sodium-potassium pump, proton pump, exocytosis, pinocytosis, phagocytosis.

Sodium-potassium pump: pumps Na+ out and K+ in; Proton pump: moves protons out using ATP; Exocytosis: expels large molecules via vesicles; Pinocytosis: cell drinking; Phagocytosis: cell eating/ingests large particles.