BIO 161 Final Exam Review - Vocabulary Flashcards/

These flashcards cover the key vocabulary and concepts from the BIO 161 Study Guide, spanning from basic scientific principles to advanced molecular biology and genetics.

Science

A systematic process for learning about the world through observation and experimentation.

Biology

The specific scientific study of life and living organisms.

Independent variable

The component of a controlled experiment that is manipulated.

Dependent variable

The component of a controlled experiment that is measured.

Hypothesis

A tentative, testable explanation for a specific observation.

Scientific theory

A broad, well-substantiated explanation supported by a large body of evidence and multiple experiments.

Hierarchical Organization of Living Things

Atom -> Molecule -> Organelle -> Cell -> Tissue -> Organ -> Organ System -> Organism -> Population -> Community -> Ecosystem -> Biosphere.

Homeostasis

The characteristic of life involving the maintenance of internal balance.

Octet rule

The rule stating that atoms are most stable with $8$ electrons in their valence shell.

Atomic number

The number of protons in an atom, which defines the element.

Atomic weight

The average mass of an element's isotopes, calculated as the sum of protons and neutrons.

Covalent bond

The strongest chemical bond, formed by the sharing of electrons.

Ionic bond

A strong chemical bond formed by the transfer of electrons, creating charged ions.

Hydrogen bond

The weakest bond, consisting of an attraction between partial charges of polar molecules.

Organic compounds

Chemical compounds that contain carbon-hydrogen bonds.

Dehydration synthesis

A chemical reaction that removes water to bond monomers into a polymer.

Hydrolysis

A chemical reaction that adds water to break a polymer back into its constituent monomers.

Denaturation

The loss of a protein's 3D shape and function due to heat or $pH$ changes.

Cell Theory

1. All living things are made of cells. 2. The cell is the basic unit of life. 3. All cells come from pre-existing cells.

Endosymbiotic theory

The theory that mitochondria and chloroplasts were once free-living bacteria engulfed by larger cells, supported by evidence of their own DNA and double membranes.

Fluid-Mosaic Theory

The concept that the plasma membrane is a flexible 'sea' where proteins float in a mosaic pattern.

Isotonic

A state where there is an equal concentration of solutes, resulting in a stable cell environment.

Hypotonic

A solution with lower solute concentration outside the cell, causing water to enter; results in lysis in animal cells and turgidity in plant cells.

Hypertonic

A solution with higher solute concentration outside the cell, causing water to leave; results in crenation in animal cells and plasmolysis in plant cells.

First Law of Thermodynamics

The law stating that energy cannot be created or destroyed, only transformed.

Second Law of Thermodynamics

The law stating that energy transformations increase entropy, appearing as disorder or heat loss.

ATP/ADP cycle

The process where high-energy $ATP$ releases a phosphate to become low-energy $ADP$, which is then recharged using energy from food.

Exergonic reaction

A reaction that releases energy, where reactants have more energy than the products.

Endergonic reaction

A reaction that requires or absorbs energy, where products have more energy than the reactants.

Activation energy ($E_a$)

The initial energy required to start a reaction, which is lowered by enzymes.

Competitive inhibition

A process where a blocker binds directly to the active site of an enzyme.

Non-competitive inhibition

A process where a blocker binds to a site other than the active site, changing the enzyme's shape.

Oxidation

The loss of electrons.

Reduction

The gain of electrons.

Aerobic cellular respiration

The production of energy using oxygen: $\text{Glucose} + O_2 \rightarrow CO_2 + H_2O + 36-38\text{ ATP}$.

Glycolysis

The anaerobic stage of respiration occurring in the cytoplasm that breaks glucose into pyruvate, yielding $2\text{ ATP}$ and $2\text{ NADH}$.

Electron Transport Chain (ETC)

The aerobic stage of respiration located in the mitochondrial cristae that uses oxygen and electrons to produce water and approximately $32-34\text{ ATP}$.

Stomata

Pores in a leaf used for gas exchange.

Photosynthesis equation

$6CO_2 + 6H_2O + \text{Light} \rightarrow C_6H_{12}O_6 + 6O_2$.

Photolysis

The splitting of water molecules during the light-dependent stage of photosynthesis to replace electrons and generate oxygen.

Binary fission

A simple form of asexual reproduction where a cell splits into two, occurring in prokaryotes like bacteria.

Mitosis

The division of somatic cells into identical clones for growth and repair, consisting of prophase, metaphase, anaphase, and telophase.

Meiosis

A two-stage cellular division process that reduces chromosome number and results in $4$ unique haploid gametes.

Crossing over

The exchange of DNA between homologous chromosomes during Prophase I to increase genetic diversity.

Independent Assortment

The random alignment of chromosome pairs during Metaphase I, which increases genetic diversity.

Diploid ($2n$)

A cell containing two complete sets of chromosomes.

Haploid ($n$)

A cell containing one set of chromosomes, typical of gametes.

Genotype

The internal genetic code of an organism (e.g., $Aa$).

Phenotype

The expressed physical trait of an organism.

Incomplete dominance

An inheritance pattern resulting in a blended phenotype, such as a pink flower from red and white parents.

Co-dominance

An inheritance pattern where both alleles are expressed simultaneously, such as blood type $AB$.

Non-disjunction

The failure of chromosomes to separate properly during meiosis, leading to aneuploidy diseases like Down Syndrome.

Transcription

The process of converting $DNA$ into $mRNA$ within the nucleus.

Translation

The process occurring at the ribosome where $mRNA$ is read in $3$-base codons to build a protein using $tRNA$.

Codon

A sequence of $3$ bases in $mRNA$ that codes for a specific amino acid.

Restriction enzymes

Biological tools used to cut $DNA$ at specific sequences.

PCR (Polymerase Chain Reaction)

A laboratory technique used for the mass copying of $DNA$.