Biol 1610 Study Guide - Biology Fundamentals, Evolution, and Chemistry

Vocabulary practice flashcards generated from the Biology 1610 Test 1 study guide covering properties of life, biological organization, scientific process, evolution, and chemical foundations.

Atom

The smallest and most fundamental unit of matter, consisting of an atomic nucleus surrounded by electrons.

Molecule

A chemical structure consisting of at least two atoms held together by one or more chemical bonds.

Organelle

Small structures that exist within cells, such as mitochondria and chloroplasts, that carry out essential cellular functions.

Cell

The smallest fundamental unit of structure and function in living organisms.

Tissue

A group of similar cells carrying out similar or related functions.

Organ

A collection of tissues grouped together performing a common function in animals or plants.

Organ System

A higher level of biological organization consisting of functionally related organs, such as the circulatory system.

Population

Individuals of a single species living within a specific area.

Community

The sum of populations inhabiting a particular area.

Ecosystem

All the living things in a particular area together with the nonliving, abiotic parts of that environment such as soil nitrogen or rainwater.

Biosphere

The highest level of biological organization representing the collection of all ecosystems and zones of life on Earth.

Biomolecules

Biological molecules produced by living cells that are critical for organisms to carry out basic biological processes such as reproduction, growth, and sustenance.

Cytosol

The fluid portion of the cytoplasm not encased by cell organelles, consisting of a complex mixture of protein filaments, dissolved molecules, and water.

Ribosomes

Cellular structures made of protein complexes and RNA that read messenger RNA and perform protein synthesis.

Central Dogma of Molecular Biology

A theory stating that genetic information flows only in one direction, from DNA to RNA to protein, or RNA directly to protein.

Scientific Method

A process of observing the natural world, posing questions, proposing possible explanations, and using objective reasoning to draw conclusions.

Hypothesis

A plausible, testable, and falsifiable proposed explanation for observations based on limited data.

Controlled Experiment

An experiment containing a control group and one or more experimental groups that differ only by a single variable being studied.

Independent Variable

The factor in research that is manipulated to observe its effect.

Dependent Variable

The outcome measured in research to evaluate the effect of the manipulated independent variable.

Scientific Theory

A well-substantiated, fact-supported explanation of an aspect of the natural world based on a body of repeatedly confirmed observations and experiments.

Natural Selection

The process leading to evolutionary change where individuals with favorable heritable traits survive environmental change and reproduce more prolifically.

Mutation

A change in DNA sequence that acts as the ultimate source of new alleles and genetic variation in a population.

Adaptation

A heritable trait that helps an organism survive and reproduce in its present environment.

Evolutionary Fitness

A measure of an individual organism's success in leaving relatively more offspring compared to others in the population.

Stabilizing Selection

A type of natural selection that favors average phenotypes and selects against extreme variations.

Directional Selection

A type of natural selection occurring during environmental changes that favors phenotypes at one end of the spectrum of existing variation.

Diversifying Selection

A type of natural selection where two or more distinct extreme phenotypes have advantages over intermediate phenotypes.

Homologous and Analogous Structures

Homologous structures share physical features inherited from a common ancestor, whereas analogous structures serve similar functions but evolved independently due to similar environmental pressures.

Bohr Model Electron Shell Capacities

The maximum capacity of electrons in each shell according to the Bohr Model: Shell 1 holds up to 2 electrons, Shell 2 holds up to 8 electrons, and Shell 3 holds up to 8 electrons.

Covalent Bond

A chemical bond formed when two atoms share one, two, or three pairs of electrons.

Ionic Bond

A chemical bond formed by electrostatic attraction between oppositely charged ions produced when atoms gain or lose electrons.

Hydrogen Bond

A weak chemical interaction between a slightly positive hydrogen atom ($\delta+$) in a polar covalent bond and a slightly negative atom ($\delta-$) on a neighboring molecule.

Nonpolar Covalent Bond

A covalent bond formed between atoms with an electronegativity difference between 0 and 0.4, resulting in equal sharing of electrons.

Polar Covalent Bond

A covalent bond formed between atoms with an electronegativity difference between 0.4 and 1.7, leading to unequal electron sharing and partial charges.

pH

A scale ranging from 0 to 14 measuring the relative concentration of free hydrogen ions ($\text{H}^+$) in a solution, calculated as $\text{pH} = -\log[\text{H}^+]$.

Buffer

A solution containing a weak acid and its conjugate base that stabilizes pH by absorbing or releasing hydrogen ions ($\text{H}^+$).

Dehydration Reaction

A chemical reaction that links monomers together into larger polymers by removing a water molecule.

Hydrolysis Reaction

A chemical reaction that breaks down large polymers into individual monomers by adding a water molecule.

Functional Groups

Specific combinations of atoms (such as hydroxyl, methyl, carbonyl, carboxyl, amino, phosphate, and sulfhydryl) that confer distinct physical and chemical properties to organic biomolecules.