BIOL1010 Unit 2 - Molecular Biology

Transcription

copies the DNA code in the genes, base for base, into Messenger RNA (mRNA)

Translation

takes place in the ribosomes (containing r RNA) - involves converting a unique nucleotide codon using Transfer RNA (tRNA) into the unique amino acids

Messenger RNA (mRNA)

Transfer RNA (tRNA)

Ribosomal RNA (rRNA)

Exon

The portions of DNA that code for genes and are expressed in an organism

Intron

Noncoding sequence; not used in protein translation

Deoxyribonucleic Acid (DNA)

Ribonucleic Acid (RNA)

RNA Polymerase

Finds Propter region and moves down the DNA strand making an RNA strand from its template

Purines

Pyrimidines

5’ to 3’

In what direction is DNA transcribed?

Promoter Region

Terminator Region

Deletion Mutation

A type of genetic mutation where one or more nucleotides are removed from a DNA sequence. This alteration can lead to a shift in the reading frame during protein synthesis, potentially resulting in a nonfunctional protein or significant changes in the organism's traits. It can occur spontaneously or due to environmental factors.

Duplication Mutation

A genetic alteration where a segment of DNA is copied, resulting in extra genetic material. This can lead to an increase in gene dosage, potentially causing phenotypic effects or contributing to diseases. It often occurs during DNA replication or through unequal crossing over in meiosis.

Inversion Mutation

A type of genetic mutation where a segment of DNA is reversed end to end. This alteration can affect gene expression and function, potentially leading to various phenotypic changes. Inversion mutations can arise from errors during DNA replication or repair and may influence evolutionary processes by altering gene arrangements.

Translocation Mutation

Flashcard

A genetic alteration where a segment of DNA is transferred from one location to another within the genome. This can occur between non-homologous chromosomes and may lead to changes in gene expression or function, potentially resulting in diseases such as cancer. It can affect the structure and regulation of genes involved in cell growth and differentiation.

Nonsense Mutation

A type of mutation that introduces a premature stop codon in the DNA sequence. This results in the production of a truncated protein, which can lead to loss of function or a nonfunctional protein. This mutation can significantly impact the organism's phenotype and is often associated with various genetic disorders.

5’ GTP cap

Prevents end degradation

3’ Poly-A tail

Attaches to end of RNA sequence and serves as nuclear export signal

Spliceosome

Removes introns from sequence and splices together exons only

Mitosis

Complex process of chromosome duplication and allocation. In order: Prophase, Metaphase, Anaphase, Telophase, Cytokinesis

Meiosis

Cell division to produce haploid gametes (sperm & egg cells) with 23 chromosomes rather than 46.

Karyotype

Homologous Chromosome

Mismatch Repair (MMR)

Base Excision Repair

Nucleotide Excision Repair

Double Strand Break

Cytokinesis

Divides the cytoplasm, organelles & cell membrane equally into two daughter cells. In plants: involves a cell plate that separates the mother cell into two equal halves. In animals: involves a cleavage furrow formed by a contracting ring of microfilaments. Result is two individual cells identical to original cell Interphase.

Gametic (Germ-line) Cell

A sex chromosome/cell

Autosomal (Somatic) Cell

A non-sexual chromosome/cell

Allele

a specific version of a gene that may produce distinguishable traits or characteristics.

Fertilization

Union of germ cells (sperm & egg)

Zygote

Fertilized egg with diploid chromosome number - one set from each parent

Prophase (Mitosis)

Chromosomes become visible (condense), centrioles separate and move to opposite poles of the cell.

Metaphase (Mitosis)

Chromosomes line up across the center of the cell and become connected to spindle fiber at their centromere.

Anaphase (Mitosis)

Sister chromatids separate into individual chromosomes and are pulled apart

Telophase (Mitosis)

Chromosomes gather at opposite ends of the cell and lose their distinct rod-like shapes. Two new near nuclear membranes then form around each of the two regions.

Prophase I (Meiosis)

Condensation of chromatin into visible chromosomes, pairing of homologous chromosomes (synapsis), and crossing over (increasing genetic diversity). It also includes the formation of tetrads and the breakdown of the nuclear envelope. This is the first step of meiosis I.

Metaphase I (Meiosis)

Alignment of homologous chromosome pairs along the cell's equatorial plane. Spindle fibers attach to the centromeres of each chromosome, ensuring that each pair is positioned for separation. This phase is crucial for genetic diversity as it allows for crossing over and independent assortment of chromosomes.

Key Features:

• Homologous chromosomes align

• Spindle fibers attach

• Precedes anaphase I

Cancer

Constant Mitosis, constant replication

Gene Regulation Pathway

Operon: Unit of DNA that contains genes that can be differentially regulated
Promoter: Unit of DNA that initiates transcription of a gene
Operator: Area that interacts with regulator proteins, part holding onto repressor molecule
Repressor: Molecule that attaches to DNA to block polymerase from binding
Activator: Protein that can attach to DNA to increase gene transcription
RNA Polymerase: Binds to DNA to transcribe RNA

Lac Operon

A genetic regulatory system found in bacteria that controls the metabolism of lactose. It consists of three structural genes that encode proteins needed for lactose uptake and breakdown, along with a promoter and an operator region. When lactose is present, it binds to the repressor, allowing transcription of the genes, enabling the bacteria to utilize lactose as an energy source.

Cell Differentiation

Gene Regulation

Determines which genes are expressed (transcribed by mRNA) within a given cell. All cells are the same genetically but turn different genes on & off to produce different proteins as needed (Helps in Cell Differentiation)

Non-homologous End Joining

Homology Directed Repair

CRISPR

Stem Cells

Induceable Pluripotent Stem Cells (IPSC)

Pluripotent

Embryonic Stem Cells

Regenerative Medicine

Synthetic Biology

Epidemic

Pandemic

Zoonoses