Chapter 1–8 Overview: Protein Synthesis, Membrane Transport, Osmosis, and Cell Life Cycle (Vocabulary)

Vocabulary flashcards covering key terms and concepts from protein synthesis, membrane transport, osmosis, and the cell life cycle as discussed in the lecture notes.

DNA

Deoxyribonucleic acid; stores the genetic instructions used to build proteins; described in class as the cell’s instruction manual.

RNA

Ribonucleic acid; a nucleic acid used to transmit the DNA message for protein synthesis; contains uracil instead of thymine.

mRNA

Messenger RNA; the RNA copy of a DNA segment that carries the protein-building code from the nucleus to the ribosome.

tRNA

Transfer RNA; brings amino acids to the ribosome and contains an anticodon that pairs with the mRNA codon.

Codon

A three-nucleotide sequence on mRNA that codes for a specific amino acid.

Anticodon

Three-nucleotide sequence on tRNA that pairs with a complementary codon on the mRNA.

Transcription

The process of converting DNA into RNA, producing an mRNA molecule.

Translation

The process of decoding the mRNA sequence to synthesize a protein by linking amino acids at the ribosome.

Amino acid

The monomer of proteins; 20 different kinds that are linked by peptide bonds to form proteins.

Peptide bond

A chemical bond that links amino acids together during protein synthesis.

Protein synthesis

The overall process of producing proteins from DNA instructions, via transcription and translation.

Primary structure

The linear sequence of amino acids in a protein.

Quaternary structure

The arrangement of multiple polypeptide subunits into a functional protein complex.

Uracil

A nitrogenous base found only in RNA; pairs with adenine during transcription/translation.

Thymine

A nitrogenous base found in DNA that pairs with adenine.

Adenine

A nitrogenous base that pairs with thymine in DNA and with uracil in RNA.

Cytosine

A nitrogenous base that pairs with guanine in both DNA and RNA.

Guanine

A nitrogenous base that pairs with cytosine in both DNA and RNA.

Base pairing (DNA)

A pairs with T and C pairs with G in DNA, forming the double helix.

Base pairing (RNA)

A pairs with U and C pairs with G in RNA.

Isotonic

A solution with equal solute concentration as the cell, resulting in no net water movement.

Hypertonic

A solution with higher solute concentration than the cell; causes water to move out of the cell.

Hypotonic

A solution with lower solute concentration than the cell; causes water to move into the cell.

Osmosis

Movement of water across a semipermeable membrane toward the area of higher solute concentration.

Semipermeable membrane

A membrane that allows some substances to pass through while restricting others.

Passive transport

Movement of substances across a membrane down their concentration gradient without using cellular energy.

Active transport

Movement of substances across a membrane against their gradient, requiring energy (ATP).

Simple diffusion

Diffusion of small, nonpolar molecules directly through the lipid bilayer without a transport protein.

Facilitated diffusion

Diffusion that requires a membrane protein to help solutes cross the membrane.

Gradient

A difference of a quantity (e.g., concentration, temperature, pressure) across space that drives movement of particles.

Concentration gradient

A difference in solute concentration between two areas, driving diffusion down the gradient.

Osmotic pressure

The pressure required to stop water movement across a semipermeable membrane, generated by osmosis.

Interphase

Stage of the cell life cycle in which the cell grows and DNA is replicated before division (G1, S, G2).

G1

Growth 1 phase; cell grows and carries out its normal functions.

S phase

Synthesis phase; DNA is replicated, doubling the genetic material.

G2

Growth 2 phase; cell prepares for mitosis with doubled organelles and cytoplasm.

Mitosis

The division of a cell’s nucleus and its content, resulting in two genetically identical daughter cells.

Prophase

First phase of mitosis, where chromosomes condense and the mitotic spindle forms.

Metaphase

Mitotic phase where chromosomes align at the cell’s equator.

Anaphase

Mitotic phase where sister chromatids separate and move to opposite poles.

Telophase

Mitotic phase where chromosomes arrive at poles and de-condense; cytoplasm divides (cytokinesis).

Cell life cycle

The sequence of events from cell formation through growth, DNA replication, and division into daughter cells.