Module 5 and 6: Heredity and Infectious Disease Practice Flashcards

Comprehensive vocabulary flashcards covering Modules 5 (Heredity) and 6 (Genetic Change / Infectious Disease) based on the lecture transcript.

Reproduction

The fundamental evolutionary process ensuring continuity of life, determined by an organism’s ability to produce fertile offspring.

Biological Fitness

The measurement of an organism’s reproductive success.

Asexual Reproduction

The primary form of reproduction for single-celled organisms, where offspring are produced by single parents without the fusion of gametes.

Natural Propagation

When plants grow and develop naturally WITHOUT human interference.

Artificial Propagation

Vegetative reproduction in plants carried out by humans in fields and laboratories.

Runner

Modified stems growing horizontally above ground, with buds forming at the nodes of runners, such as strawberries.

Rhizome

Modified stems that typically grow horizontally along or beneath the ground, acting as storage sites for proteins and starches, such as ginger.

Bulb

Round, swollen parts of a stem found underground containing a new central shoot, such as onions and tulips.

Tuber

Vegetative organs developed from stems or roots that become swollen from storing nutrients, such as potatoes and yams.

Grafting

A technique where a cutting from one plant is attached to the rooted stem of another plant, eventually integrating tissues to develop as a single plant.

Tissue Culture

Culturing plant cells from a parent plant in a sterilized medium until a callus forms and develops into plantlets.

Binary Fission

A form of asexual reproduction occurring in prokaryotic microorganisms and some invertebrates where an organism splits into two separate organisms.

Budding

Asexual reproduction resulting from the outgrowth of a part of a cell or body region leading to separation into two individuals, such as in hydras.

Fragmentation

A form of asexual reproduction where the body breaks into parts with subsequent regeneration into separate individuals, as seen in sea stars.

Parthenogenesis

A form of interchanging reproduction where an egg develops without fertilisation, resulting in haploid or diploid offspring depending on the species.

Sexual Reproduction

Reproduction involving the fusion of a haploid female gamete (egg cell) and a haploid male gamete (sperm cell) to produce a diploid zygote.

External Fertilisation

Fertilisation occurring outside the body, typically in watery environments, where gametes are shed directly into the open environment.

Internal Fertilisation

Fertilisation occurring inside the body of the female, characteristic of most land and some marine organisms.

Gymnosperm

A type of plant that undergoes sexual reproduction but does not produce seeds, such as moss and ferns.

Angiosperm

A type of plant that undergoes sexual reproduction in flowering plants and conifers that do produce seeds.

Carpel

The female parts of a flower, consisting of the stigma, the style, and the ovary.

Stamen

The male parts of a flower, consisting of the anther and the filament.

Chromosomes

Thread-like structures made up of DNA.

Karyotype

The number and visual appearance of the chromosomes in cell nuclei.

Chromatin

A complex of DNA and protein found in eukaryotic cells.

Centromere

The structure that links a pair of sister chromatids together.

Chromatid

One of two identical halves of a chromosome.

Mitosis

Cell division essential for growth, repair of damaged tissues, and replacement of worn-out cells in multicellular organisms.

Interphase

The step in the cell cycle where the cell grows and DNA materials are replicated in preparation for mitosis, consisting of $G1$, $S$, and $G2$ phases.

Cytokinesis

The final step of mitosis involving the division of the cytoplasm while the nucleus completes division.

Stem Cells

Specialised human cells that are able to develop into many different cell types.

Meristem Cells

Plant tissues composed of undifferentiated self-renewing stem cells from which most plant structures arise.

Meiosis

A type of reduction division occurring in sexual reproductive organs where a diploid cell divides into 4 haploid daughter cells to form gametes.

Diploid

Containing 2 copies of each chromosome.

Haploid

Containing 1 copy of each chromosome.

DNA (Deoxyribonucleic acid)

A double-stranded helical molecule made of nucleotides consisting of a 5 carbon deoxyribose sugar, a phosphate group, and one of 4 nitrogen bases.

DNA Replication

A semi-conservative process ensuring genetic material is copied exactly to produce two identical double-stranded DNA molecules from one original double helix.

Helicase

The enzyme that unzips DNA by disrupting hydrogen bonding between base pairs to separate strands into a y-shape known as the replication fork.

DNA Polymerase

Enzymes responsible for creating new strands of DNA (elongation) and ensuring correct nitrogenous bases are paired.

Ligase

The enzyme that 'glues' newly formed DNA strands together during replication.

Okazaki Fragments

Small chunks of DNA copied backwards (away from the opening) on the lagging strand during DNA replication.

Polypeptide

Polymers of amino acids joined together by peptide bonds.

Proteins

Large complex macromolecules made up of one or more polypeptide chains.

Messenger RNA (mRNA)

A single-stranded nucleic acid that carries information from DNA in the nucleus to ribosomes in the cytoplasm.

Transfer RNA (tRNA)

A molecule with an anticodon on one end that attracts complementary bases on mRNA and a specific amino acid on the other end.

Transcription

The process where RNA polymerase binds to a promoter sequence and creates a growing mRNA strand complementary to the DNA template.

Translation

The process where ribosomes read mRNA codons and tRNA transports corresponding amino acids to form a polypeptide chain.

Zygote

A fertilised egg.

Implantation

The attachment of a fertilised egg to the wall of the uterus, occurring $5-7$ days after fertilisation.

hCG (Human Chorionic Gonadotropin)

A hormone made almost exclusively in the placenta during pregnancy, primarily in the first trimester.

Oxytocin

A hormone that stimulates uterine contractions in labour and stimulates contractions of breast tissue to aid in lactation.

Prolactin

A hormone released by the pituitary during pregnancy and lactation that prepares breasts for milk production.

Genes

Units of inheritance that determine particular characteristics and code for specific polypeptides.

Alleles

Alternative forms of a gene that determine a given characteristic, occur in pairs, and vary in effect.

Genotype

A pair of genes containing information for a characteristic.

Phenotype

A physical expression or observable characteristic.

Law of Segregation

Mendel's First Law stating that parental genes are randomly separated to sex cells so that sex cells contain only one gene pair.

Law of Independent Assortment

Mendel's Second Law stating that genes for different traits are sorted separately from one another.

Codominance

A pattern of inheritance where both alleles are expressed as separate, unblended phenotypes, such as in roan cattle.

Pedigree

A graphical representation of inheritance patterns of a particular trait in related individuals over generations.

Gene Pool

A combination of all the genes (including alleles) present in a reproducing population or species.

Allele Frequency

The proportion of the population that has a particular allele.

SNPs (Single Nucleotide Polymorphisms)

A single base pair variation in the genome used as genetic markers.

PCR (Polymerase Chain Reaction)

A technique to make copies of a piece of DNA (amplification) involving denaturation ($96\,^\circ\text{C}$), annealing ($55-65\,^\circ\text{C}$), and extension ($72\,^\circ\text{C}$).

Gel Electrophoresis

A technique used to separate DNA fragments based on their size and charge by running a current through a gel.

STRs (Short Tandem Repeats)

Sections of non-coding DNA that are repeated many times over and are unique to each individual.

Mutagens

Environmental agents that alter DNA and cause mutations.

Bioaccumulation

When a harmful substance gets absorbed by an organism at a higher rate than it is excreted.

Biomagnification

The tendency of pollutants to concentrate as they move from one trophic level to the next.

Silent Mutations

Point mutations in the DNA sequence that do not cause a change in the amino acid, resulting in no effect on proteins.

Nonsense Mutations

Mutations that change an amino acid to a stop codon, resulting in a non-functional protein.

Aneuploid

The presence of an abnormal number of particular chromosomes, such as trisomy.

Polyploidy

A condition resulting from cells and organisms containing more than two full sets of chromosomes.

Gene Flow

The movement of genetic material from one group to another, mediated by reproduction and migration.

Genetic Drift

The change in frequency of an existing gene variant in a population due to random chance, which can cause variants to disappear.

Bottleneck Effect

A mechanism of genetic drift that occurs when the size of a population is severely reduced.

Founder Effect

A mechanism of genetic drift that occurs when a new colony is started by a few members of the original population.

SCNT (Somatic Cell Nuclear Transfer)

A cloning process where the nucleus of a somatic cell is injected into an enucleated egg and treated with electricity.

Transgenic Species

A species created by taking a gene from one species and inserting it into the germline genome (DNA) of another species.

Pathogen

Any organism or infective agent that lives in or on another living organism and causes a disease.

Fomites

Objects that can host pathogens for short periods of time and contribute to indirect transmission.

Endemic

A disease consistently present with predictable spread and rates within a particular region.

Prions

Proteinaceous infectious particles that trigger normal proteins in the brain to fold abnormally and contain no genetic material.

Phagocytosis

The process by which specialised white blood cells (phagocytes) surround, enclose, and destroy foreign particles with enzymes.

Homeostasis

The maintenance of a relatively constant internal environment in an organism for optimal metabolic efficiency.