Biology Classification and Genetics Review

These flashcards cover key concepts in biological classification, genetics, and related processes, reflecting the content from the lecture notes.

Domain

The highest taxonomic rank in the biological classification system.

Kingdoms

The second highest taxonomic rank, which includes six major categories.

Phylum

A taxonomic rank below kingdom that groups together related classes.

Class

A taxonomic rank below phylum that groups related orders.

Order

A taxonomic rank below class that groups related families.

Family

A taxonomic rank below order that groups related genera.

Genus

A taxonomic rank below family that groups species that are closely related.

Species

The basic unit of biological classification, a group of organisms that can interbreed.

Eubacteria

One of the six kingdoms, consisting of true bacteria.

Archaea

One of the three domains, consisting of ancient prokaryotic microorganisms.

Eukarya

One of the three domains, consisting of organisms with eukaryotic cells.

Biological species concept

Species are defined as groups of populations that can interbreed and produce fertile offspring.

Morphological species concept

Species are defined based on physical form and structure.

Phylogenetic species concept

Species are defined based on their evolutionary history and common ancestry.

Binomial nomenclature

A two-part naming system for species consisting of genus and specific epithet.

Prokaryotic cells

Cells lacking membrane-bound organelles and a nucleus.

Eukaryotic cells

Cells that contain a nucleus and membrane-bound organelles.

Endosymbiotic theory

Theory suggesting that eukaryotic cells evolved from prokaryotic cells through symbiosis.

Gram-positive bacteria

Bacteria that have thick peptidoglycan cell walls and stain purple.

Gram-negative bacteria

Bacteria that have thin peptidoglycan walls and an outer membrane, staining pink.

Fungi

Eukaryotic organisms that are mostly multicellular with chitin cell walls.

Hyphae

Filamentous structures that make up the mycelium of fungi.

Spores

Asexual or sexual reproductive units in fungi.

Protists

Mostly unicellular eukaryotes that are grouped as algae, protozoa, and slime molds.

Multicellular organisms

Organisms made of multiple cells, such as animals and plants.

Photosynthesis

Process by which plants and some protists convert light energy into chemical energy.

Gymnosperms

Seed-producing plants that do not form flowers.

Angiosperms

Flowering plants that produce seeds within a fruit.

Viruses

Non-cellular entities that cannot reproduce or carry out metabolism independently.

Lytic cycle

Viral reproduction cycle where the virus immediately produces new particles and lyses the host cell.

Lysogenic cycle

Viral reproduction cycle where viral DNA integrates into the host DNA and can remain dormant.

DNA structure

A double helix made of two strands of nucleotides joined by base pairs.

Chromosome

A coiled DNA-protein structure containing many genes.

Homologous chromosomes

Matching pairs of chromosomes containing the same sequence of genes.

Autosomes

Non-sex chromosomes.

Sex chromosomes

Chromosomes that determine biological sex (X and Y in humans).

Gene

A segment of DNA that codes for a specific trait.

Alleles

Different versions of a gene.

Law of segregation

Two alleles for a gene separate into different gametes during meiosis.

Law of independent assortment

Alleles for different genes sort independently during gamete formation.

Homozygous

An organism with two identical alleles for a trait.

Heterozygous

An organism with two different alleles for a trait.

Punnett square

A diagram used to predict the genotypes of offspring from a genetic cross.

Meiosis

A type of cell division that reduces the chromosome number and produces haploid gametes.

Karyotype

An ordered profile of an individual's chromosomes.

Pedigree

A chart that tracks inheritance of traits through generations.

Incomplete dominance

A genetic scenario where heterozygotes show a blended phenotype.

Codominance

A genetic scenario where both alleles are fully expressed in heterozygotes.

Polygenic trait

A trait controlled by multiple genes.

Sex-linked traits

Traits associated with genes located on sex chromosomes.

Autosomal dominant disorder

A genetic disorder that requires only one copy of the defective gene.

Autosomal recessive disorder

A genetic disorder that requires two copies of the defective gene to manifest.

Trisomy 21

A genetic disorder caused by the presence of an extra chromosome 21, leading to Down syndrome.