Lab 1-3 Review: Phylogeny, Plant/Animal/Fungi, Prokaryotes vs Eukaryotes

A comprehensive set of Q&A flashcards covering phylogeny, cladistics, shared traits among eukaryotes, plant/animal/fungi differences, prokaryotes vs eukaryotes, major eukaryotic supergroups, protist locomotion, and societal relevance to prepare for exams.

What is phylogeny?

The evolutionary history of organisms.

What is cladistics?

Grouping organisms by shared derived characteristics.

What is a cladogram?

A tree diagram that shows hypothesized evolutionary relationships among taxa.

In building a cladogram, what is an outgroup?

An organism that diverged earliest and serves as a baseline for comparison.

What are ancestral vs. derived traits in cladistics?

Ancestral traits are old features; derived traits are newer features used to distinguish taxa.

What does parsimony mean in cladistics?

The simplest explanation (tree with the fewest evolutionary changes) is preferred.

What does monophyletic mean?

A group that includes an ancestor and all of its descendants.

What does paraphyletic mean?

An ancestor and only some of its descendants.

What does polyphyletic mean?

A group formed from unrelated lineages, often based on convergent traits.

What are homologous traits?

Traits shared because of a common ancestry.

What are analogous traits?

Similar traits arising from convergent evolution, not shared ancestry.

Why is DNA data often preferred over morphology in phylogenetics?

Because morphology can be misleading due to convergent evolution; DNA tracks mutations and distinguishes close relatives.

Name some molecular data types used in phylogenetics.

Mitochondrial DNA, ribosomal genes, STRs, SNPs.

Name a shared eukaryotic trait.

Nucleus with linear DNA.

Name another shared eukaryotic trait.

Membrane-bound organelles (mitochondria, ER, Golgi).

Name another shared eukaryotic trait.

Cytoskeleton for cellular structure.

Plants: what is the composition of cell walls?

Cell walls are made of cellulose.

Plants: how do they obtain energy?

Autotrophic via chloroplasts for photosynthesis.

Plants have what life cycle pattern?

Alternation of generations (haploid and diploid stages).

Animals: do they have cell walls?

No; animals lack cell walls.

Animals: how do they obtain nutrients?

Heterotrophic (ingest food).

Animals: which body form dominates?

Multicellular diploid stage is dominant.

Fungi: what is the composition of their cell walls?

Chitin.

Fungi: how do they obtain nutrients?

Heterotrophic; absorb nutrients via enzymes.

Fungi: what are hyphae and mycelium?

Hyphae are filamentous bodies; mycelium is a network of hyphae.

Fungi: typical body organization?

Mainly mycelium with reproductive structures like mushrooms and sporangia.

Plants, Animals, Fungi: how are tissues and organs organized differently?

Plants: tissues (vascular, dermal, ground) and organs (root, stem, leaf); Animals: tissue types (epithelial, muscle, connective, nervous), organs, systems; Fungi: mainly mycelium with reproductive structures.

Colonies vs Tissues: what is the difference?

Colony = cells living together with little specialization; tissue = coordinated, specialized cells functioning as a unit.

Daily-life examples of plants' benefits and harms?

Beneficial: crops, medicine, oxygen; Harmful: poison ivy, invasive weeds.

Daily-life examples of animals' benefits and harms?

Beneficial: pets, livestock, pollinators; Harmful: mosquitoes, parasites.

Daily-life examples of fungi's benefits and harms?

Beneficial: yeast, antibiotics; Harmful: athlete's foot, mold.

Prokaryotes: do they have a nucleus?

No; DNA is located in a nucleoid region.

Prokaryotes: do they have membrane-bound organelles?

No; they lack membrane-bound organelles.

Prokaryotes: cell wall composition?

Peptidoglycan in the cell wall.

Prokaryotes: how do they reproduce?

Binary fission.

Gram-positive bacteria: staining and cell wall?

Thick peptidoglycan; stains purple.

Gram-negative bacteria: staining and cell wall?

Thin peptidoglycan with outer membrane; stains pink.

Eukaryotes: do they have a true nucleus?

Yes; true nucleus with linear chromosomes.

Eukaryotes: typical organelles?

Mitochondria, ER, Golgi; chloroplasts in plants.

Eukaryotes: size and modes of reproduction?

Generally larger; reproduction can be sexual or asexual.

Eukaryotic supergroups: Excavata examples?

Euglena (photosynthetic, flagellated); Trypanosoma (sleeping sickness).

Eukaryotic supergroups: Alveolates and their examples?

Paramecium (cilia); Dinoflagellates (red tides).

Eukaryotic supergroups: Stramenopiles and examples?

Diatoms (silica shells); Brown algae (multicellular, kelp).

Eukaryotic supergroups: Rhizaria examples?

Foraminifera (calcium shells); Radiolarians (silica skeletons).

Eukaryotic supergroups: Archaeplastida examples?

Red algae, green algae (Ulva, Spirogyra), plants.

Eukaryotic supergroups: Unikonta examples?

Amoebas, fungi, animals.

Protist locomotion: Cilia and an example?

Cilia beat in coordinated waves; Paramecium is a ciliate.

Protist locomotion: Flagella and an example?

Flagella whip-like tails; Euglena uses flagella.

Protist locomotion: Pseudopodia and an example?

Extensions of cytoplasm used by Amoeba and forams.

Why are protists and bacteria important in society?

Bacteria: probiotics, nitrogen fixation, antibiotics (positive); pathogens and antibiotic resistance (negative). Protists: algae produce oxygen and form the base of the food chain; dinoflagellates can cause harmful algal blooms.

What ecological roles do diatoms and brown algae play?

Diatoms produce oxygen; brown algae serve as a food source.

What disease is caused by Trypanosoma (Excavata)?

African sleeping sickness.

Exam tip: when reading a cladogram, what should you consider?

Check whether the grouping reflects monophyly and consider parsimony; focus on shared derived traits.