Biology Exam 1 Review Flashcards

Vocabulary practice flashcards generated from the biology lecture notes across Chapters 1, 2, 3 (Water), and Lab BIO.

Autotroph

An organism that obtains energy by making its own food as a self-feeder, such as through photosynthesis.

Heterotroph

An organism that obtains energy by needing food from other sources rather than producing it itself.

Atom

The smallest functional unit of matter and element that retains all the chemical properties of that element.

Molecule

A structure defined by two or more atoms held together by covalent bonds.

Organelles

Specialized structures within a cell that make up cells and tissues, found only in eukaryotic cells.

Genome

The entire gene DNA present in an organism.

DNA

Heritable information and the substance of genes that directs all of the cell's activities.

Negative Feedback

The most common form of cellular chemical regulation where the response reduces or dampens the initial stimulus (e.g., sweating).

Positive Feedback

A chemical feedback process that increases or accelerates synthesis/output (e.g., breastfeeding and milk release).

Carlus Linnaeus

The founder of taxonomy (1707–1778) who established the system for classifying and naming organisms using Genus + species.

Taxonomy

The branch of biology concerned with classifying and naming organisms.

Three Domains of Life

Bacteria (unicellular prokaryotes), Archaea (unicellular prokaryotes), and Eukarya (unicellular or multicellular eukaryotes).

Catastrophism

The theory that major geological changes have played a primary role in Earth's history and evolution.

Evolution

Modified descent from common ancestors, characterized by a change in allele frequency in a population over time through natural selection.

Quantitative Observations

Observations that consist of numbers and units (e.g., $0^\text{o}\text{F}$).

Qualitative Observations

Descriptive observations made without the use of numerical units (e.g., 'the water is clear').

Central Dogma Pathway

The process where DNA is transcribed into RNA, which is then translated into proteins.

Atomic Number

The total number of protons found in the nucleus of an atom.

Atomic Mass

The total sum of protons plus neutrons in an atom, measured in daltons.

Isotopes

Atoms of the same element that have equal numbers of protons and electrons but different numbers of neutrons.

Half-Life

The time required for half of a radioactive sample to undergo decay.

Subatomic Particle Mass

Protons and neutrons each have a charge mass of $1\text{ amu}$, while electrons have a mass of $\frac{1}{2000}\text{ amu}$.

Octet Rule

The principle that atoms are least likely to react and are most stable when their outer valence shell is filled with 2 or 8 electrons.

Covalent Bonds

Strong chemical bonds formed when two atoms share valence electrons to fill their outer shells.

Electronegativity

An atom's attraction for shared electrons in a covalent bond.

Non-Polar Covalent Bond

A covalent bond formed between atoms with similar electronegativities, resulting in equal sharing of electrons.

Polar Covalent Bond

A covalent bond formed by unequal sharing of electrons, creating polarity within the molecule.

Ionic Bonds

Bonds formed when electrons are completely transferred from one atom to another, creating an attraction between ions of opposite charge.

Hydrogen Bonds

Weak attractions that occur specifically between separate molecules (e.g., between individual water molecules).

Chemical Equilibrium

The state reached when the rates of the forward reaction and the reverse reaction become equal.

Cohesion

The attraction between like water molecules that creates surface tension and helps move water up plants through xylem.

Adhesion

The attraction from water molecules to other different substances.

Hydrophobic

Non-polar liquids that have no charge and do not dissolve in water.

Hydrophilic

Polar molecules and ionic compounds that readily dissolve in water.

Molarity Formula

$$\text{molarity} = \frac{\text{moles solute}}{\text{liters solution}}$$

pH Scale

Calculated as $pH = -\log([H^+])$, where a pH below $7$ is acidic and a pH above $7$ is basic.

Buffer

A solution consisting of weak acids and conjugate bases that resists changes in pH by accepting hydrogen ions when acids are added and donating hydrogen ions when bases are added.

Proganthanism

A skull measurement describing how much the jaw protrudes forward.

Fragmain Magnam

The opening (hole) in the base of the skull where the spine connects to the brain.

Nachal Area

The area on the posterior skull where neck muscles attach.

Brow Ridge

A bony ridge on the skull that serves to reinforce weaker facial bones.

Zygomatic Arch

A bone arch on the skull that provides a gap for chewing muscles to pass through.

Sagittal Crest

A ridge running along the top of the skull that anchors strong jaw muscles, commonly prominent in plant diets.

Canine Diastema

A distinct opening or space in the tooth row designed to accommodate large canine teeth.