Attributes of Living Systems - Study Guide for Exam 4

A collection of vocabulary flashcards covering concepts from DNA structure and replication, gene expression, mutations, and biotechnology.

Double Helix

The structural shape of DNA, consisting of two strands twisted around each other.

Chargaff's Rules

In DNA, the amount of adenine equals thymine, and the amount of cytosine equals guanine.

Complementary Strands

DNA strands that match with each other's base pairs (A-T and C-G) and have opposite orientations.

Anti-parallel

Refers to the opposite directional arrangements of the two strands of DNA.

Semiconservative Replication

A method of DNA replication where each new DNA helix consists of one old strand and one new strand.

Origins of Replication

Specific locations on a DNA molecule where replication begins.

Helicase

An enzyme that unwinds and separates the two strands of DNA during replication.

DNA Polymerase

An enzyme that synthesizes new DNA strands by adding nucleotides to a growing chain.

Primase

An enzyme that synthesizes RNA primers to initiate DNA replication.

Ligase

An enzyme that joins DNA fragments by forming covalent bonds between the sugar-phosphate backbones.

Primers

Short sequences of RNA or DNA that provide a starting point for DNA synthesis.

Okazaki Fragments

Short DNA fragments synthesized on the lagging strand during DNA replication.

Telomeres

The protective ends of chromosomes that prevent degradation and maintain chromosome stability.

Central Dogma

The framework describing the flow of genetic information from DNA to RNA to protein.

Template Strand

The strand of DNA that serves as a guide for RNA synthesis during transcription.

Gene Transcription

The process of copying a segment of DNA into messenger RNA (mRNA).

Promoter Region

A sequence of DNA that initiates transcription by binding RNA polymerase.

Terminator Region

A sequence that signals the end of transcription.

Ribosome Assembly

The process whereby ribosomal RNA and proteins come together to form functional ribosomes.

Genetic Code

The set of rules used to translate the information encoded within mRNA into proteins.

Codons

Sequences of three nucleotides in mRNA that correspond to specific amino acids.

Point Mutation

A change in a single nucleotide in the DNA sequence.

Silent Mutation

A mutation that does not change the amino acid sequence of a protein.

Lytic Cycle

The viral replication cycle where a virus infects a host cell, replicates, and then lyses the cell.

Lysogenic Cycle

A viral replication cycle where the viral genome integrates into the host DNA and replicates alongside it.

Reverse Transcriptase

An enzyme used by some viruses to transcribe their RNA genome into DNA.

Restriction Enzymes

Proteins that cut DNA at specific sequences, used in genetic engineering.

cDNA (complementary DNA)

Synthetic DNA created from an RNA template via reverse transcription.

Gel Electrophoresis

A method used to separate DNA fragments based on size and charge.

Nucleic Acid Probes

Molecules that can detect specific sequences of nucleotides in DNA.

Polymerase Chain Reaction (PCR)

A technique used to amplify specific DNA sequences.

Cloning Vectors

DNA molecules used to transport foreign genetic material into another cell.

Genetically Modified Organisms (GMOs)

Organisms whose genomes have been altered through genetic engineering.

Gene Therapy

A technique that modifies genes to treat or prevent diseases.