BIO EXAM

Charles Darwin and Alfred Wallace

Influential scientists in the field of evolution.

Scientific ideas in the 1800s

Focused on similarities and differences between organisms.

Classification system for organisms

Developed to understand the diversity of life.

Geology and extinct organisms

Helped understand the Earth's history and the existence of extinct organisms.

Lamarck's theory

Proposed that organisms change over time in response to their environment.

Darwin's voyage on the HMS Beagle

Collected specimens and observed the diversity of life.

Darwin's question

How species originated and why there were variations within each continent.

Importance of the Galapagos Islands

Contained unique species not found elsewhere.

Darwin's big idea

Species change over time through natural selection, leading to the evolution of new species.

Alfred Wallace's theory

Independently came up with a similar theory of evolution through natural selection.

Fossils as evidence of evolutionary change

Show relationships between organisms.

Transitional fossils

Demonstrate intermediates between ancestral forms and their descendants.

Biogeography

Studies the geographical distributions of organisms and the role of barriers in speciation.

Convergent evolution

Occurs when distantly related organisms evolve similar traits independently.

Human-driven selection

Artificial breeding can lead to the evolution of desired characteristics.

Molecules and atoms

Basis of evolution, determine characteristics and functions of biological molecules.

DNA and genes

Play a crucial role in inheritance and the production of proteins.

Evolution in populations

Changes in gene frequencies within a population over time.

Population and species

Defined by interbreeding and genetic diversity.

Genetic diversity

Arises from different alleles and is critical for coping with environmental changes.

Mutations

Changes in DNA that contribute to genetic diversity.

Genetic recombination

Occurs during sex cell division and contributes to genetic diversity.

Evolutionary drivers

Natural selection, sexual selection, genetic drift, and migration (gene flow).

Taxonomy and Systematics

Science of naming and classifying living and extinct species.

Taxonomy

Branch of systematics that classifies organisms before determining evolutionary relationships.

Domains of life

Bacteria, Archaea, and Eukaryotes.

Prokaryotes vs

Differences in size, cellular structure, and internal membranes.

Domain Eukarya

Contains protists, which are single-celled eukaryotes with extreme diversity.

Current classification system

Domain, Supergroup, Kingdom, Phylum, Class, Order, Family, Genus, Species.

Binomial nomenclature

Two-part naming system using genus and species names.

Phylogenetic trees

Diagrams of evolutionary relationships between species.

Terminal taxa

Living or extinct organisms at the tips of a phylogenetic tree.

Nodes

Points where branches come together, representing common ancestors.

Clades

Groups with a common ancestor and all of its descendants.

Sister groups

Pairs of terminal taxa or clades that branch from a common node.

Branch lengths

Indicate relative time and evolutionary changes between nodes.

Homologous features

Similarities in morphology, behavior, or molecular sequences used to determine relationships.

Cladistics

Classification of species based on specific traits to determine evolutionary relationships.

Cladogram

Phylogenetic tree comparing specific traits or characteristics among organisms.

Characters

Features being compared, such as morphology, physiology, behavior, ecology, or molecular sequences.

Primitive vs

Primitive characters occurred before the last common ancestor, while derived characters occurred in the last common ancestor.

Cladogram branch points

Where two species differ in a character, indicating where lineages separated.

Molecular clocks

Use DNA or protein sequences to determine when species diverged from each other.

Evolution of anole lizards

Example of a genetic tree showing evolutionary relationships.

Organic molecule

A molecule that contains carbon (C) and hydrogen (H), such as C6H12O6.

Inorganic molecule

A molecule that does not contain both carbon (C) and hydrogen (H), such as CO2 or SO2.

Autotrophs

Organisms that produce organic molecules from inorganic sources, such as converting CO2 into C6H12O6 through photosynthesis.

Heterotrophs

Organisms that obtain organic molecules from other organisms.

Prokaryotes

Single-celled organisms that lack a nucleus and other membrane-bound organelles.

Protists

Eukaryotic organisms that have subcellular organelles and include organisms like algae and protozoa.

Endosymbiosis

A mutually beneficial arrangement where one organism lives inside another, such as bacteria becoming mitochondria.

Fusion

The joining of two organisms, such as archaea and bacteria, resulting in the formation of mitochondria.

Mitochondria

Critical organelles where ATP is generated, the cellular energy molecule, and where oxygen is used.

Chloroplasts

Organelles where photosynthesis occurs, using CO2 and releasing O2, and making biological molecules.

Ecology

The relationship between organisms and their environment, including where organisms live and how they obtain nutrients.

Algae

Photosynthetic protists.

Protozoa

Non-photosynthetic protists that obtain organic molecules or other organisms for nutrition.

Fungus-like protists

Protists with threadlike bodies that absorb nutrients from the environment.

Plankton

Small organisms that swim or float in water, including protists, bacteria, viruses, and small animals.

Amoeboid movement

Movement characterized by extending cytoplasm into lobes and the rest of the cell following.

Diploid

Having two sets of chromosomes, most human cells are diploid.

Haploid

Having one set of chromosomes, sex cells are haploid.

Meiosis

The process of cell division that results in the formation of haploid gametes and adds genetic diversity.

Gametes

Haploid cells that fuse with other haploid cells to form a diploid zygote.

Spores

Haploid or diploid cells that divide using mitosis and are formed by protists, fungi, and plants.

Alternation of generations

A life cycle used by multicellular protists and plants, where there is a multicellular haploid gametophyte and a multicellular diploid sporophyte.

Cryptomycota

A phylum of fungi that diverged early and may be related to fungi.

Chitin

A carbohydrate found in fungal cell walls.

Osmotrophy

A type of absorptive nutrition where fungi secrete enzymes to break down complex organic molecules outside the organism and absorb smaller organic molecules as food.

Yeasts

Unicellular fungi.

Hyphae

Branched filaments of multicellular fungi that are connected end to end and form a mycelium.

Mycelium

A mass of hyphae.

Fruiting body

A reproductive structure of fungi made of hyphae, such as a mushroom.

Fragmentation

A method of asexual reproduction in fungi where pieces of mycelium break off and move to a new location.

Budding

A method of asexual reproduction in fungi where a daughter nucleus moves into a daughter cell before separating.

Asexual spore

A single cell with the ability to develop into a new organism without fusing with another cell.

Conidia

Specialized structures in fungi that produce asexual spores and are dispersed by wind and rain.

Haploid dominant

Most fungal species spend the majority of their time in the haploid state (1n) during asexual reproduction.

Asexual reproduction

A type of reproduction in fungi where haploid cells divide to produce genetically identical haploid cells.

Sexual reproduction

A type of reproduction in fungi where haploid cells of different mating types fuse to form a diploid zygote, which undergoes meiosis to form haploid sexual spores.

Fruiting body

The reproductive structure of a fungus that releases sexual spores and grows from a substrate after mating.

Mucoromycota

A phylum of fungi that live on land, do not have flagella at any stage of their life cycle, and often display symbiotic relationships with bacteria, protists, plants, and animals.

Mycorrhizal fungi

Fungi that form mutually beneficial associations with plant roots, providing nutrients to the plants and receiving organic molecules from the soil in return.

Plant decomposers

Fungi that break down organic molecules from dead plants into component parts, which are then used to make new molecules.

Ascomycota

A phylum of fungi that mostly live on land, including both multicellular species and yeasts, and can act as decomposers, pathogens of plants or animals, or form mutualistic relationships with other organisms.

Lichens

A mutualistic relationship between a photosynthetic protist and a fungus, with Ascomycota being the fungal part in 98% of lichens.

Endophytic fungi

Fungi that live inside plants, protecting them from predation and inhibiting bacterial growth.

Basidiomycota

A phylum of fungi closely related to Ascomycota, characterized by the presence of fruiting bodies and their ecological roles as decomposers, plant symbionts, or pathogens.

Decomposers

Fungi that play a major role in carbon cycling by breaking down carbon compounds in wood, making carbon bioavailable to other organisms.

Mycelium

The vegetative part of a fungus, consisting of a network of hyphae, which surrounds and penetrates the roots of host trees in the case of Basidiomycota.

Wood-wide web

Underground resource-sharing networks between trees and fungi, facilitating the exchange of nutrients and information.

Basidiocarps

The multicellular fruiting bodies of Basidiomycota fungi, which produce haploid spores called basidiospores through meiosis.

Basidiospores

Haploid spores produced by Basidiomycota fungi through meiosis on the basidia, club-shaped cells found on the underside of the fruiting bodies.

Asci

Sac-like structures in Ascomycota fungi where spores are produced.