BIOL112 Real Flashcards Exam 3

Front: What are the two main differences between eukaryotic and prokaryotic cells?

Back: Eukaryotes have a nucleus and membrane-bound organelles; prokaryotes do not.

Front: How did the nucleus and ER originate in eukaryotic cells?

Back: By invagination of the plasma membrane in a prokaryotic ancestor.

Front: Endosymbiosis

Back: Process by which mitochondria and chloroplasts originated in eukaryotic cells.

Front: Why are chloroplast-containing organisms not monophyletic?

Back: Because secondary endosymbiosis spread chloroplasts across unrelated eukaryotic lineages.

Front: Evidence for endosymbiosis in eukaryotes

Back: Mitochondria/chloroplasts have their own DNA, double membranes, and replicate independently.

Front: Excavata

Back: Protists with modified mitochondria, feeding grooves, and unique flagella.

Front: Diplomonads

Back: Protists with two nuclei and anaerobic metabolism; often parasitic (e.g., Giardia).

Front: How does Giardia survive in the human intestine?

Back: Its two nuclei help manage gene expression for survival and it forms cysts to resist harsh conditions.

Front: Parabasalids

Back: Protists with basal bodies; some live symbiotically in termite guts; Trichomonas is pathogenic in humans.

Front: Euglenids

Back: Protists with eyespots for detecting light, contractile vacuoles for osmoregulation, and mixotrophic nutrition.

Front: Kinetoplastids

Back: Flagellated parasites like Trypanosoma that evade drugs via surface protein changes.

Front: Name the three groups of the SAR supergroup

.Back: Stramenopiles, Alveolates, Rhizaria.

Front: Alveolates

Back: Protists with alveoli under the membrane; includes ciliates, apicomplexans, and dinoflagellates.

Front: What is the ecological role of dinoflagellates?

Back: Photosynthesis, symbiosis with corals (zooxanthellae), and sometimes harmful algal blooms.

Front: Apicomplexans

Back: Parasitic protists with an apical complex used to invade host cells (e.g., Plasmodium).

Front: How does Plasmodium use different hosts in its life cycle?

Back: It alternates between mosquito (sexual stages) and human (asexual stages).

Front: Ciliates

Back: Covered with cilia; macronucleus for daily function, micronucleus for sexual reproduction.

Front: How do contractile vacuoles and stigma function in euglenids?

Back: Vacuoles expel excess water; stigma detects light for photosynthesis.

Front: Stramenopiles

Back: Hairy and smooth flagella; includes diatoms, brown algae, oomycetes.

Front: What is unique about diatom shells?

Back: Made of silica, often with intricate patterns, providing protection and buoyancy.

Front: Brown algae vs vascular plants

Back: Brown algae have root-, leaf-, and stem-like structures but lack true vascular tissue.

Front: Oomycetes

Back: Water molds; some are parasitic on plants, fish, or amphibians.

Front: Rhizaria

Back: Includes Radiolarians, Foraminifera, and Cercozoa; often have elaborate shells and use pseudopodia.

Front: How do Foraminifera obtain food?

Back: They extend pseudopodia to capture prey and trap food particles.

Front: Archaeplastida

Back: Red algae (Rhodophyta) and green algae; photosynthetic, ancestors of land plants.

Front: How do Amoebozoa move and feed?

Back: Using pseudopodia.

Front: Opisthokonta

Back: Includes fungi and animals; choanoflagellates resemble sponge collar cells.

Front: Evolutionary relationship between green algae and land plants

Back: Land plants evolved from green algae (Charophyta) due to similarities in chlorophyll, cell walls, and reproductive structures.

Front: What major problems did plants face moving to land?

Back: Desiccation, structural support, reproduction without water, nutrient acquisition.

Front: Trend in haploid vs. diploid stages in land plants

Back: Gametophyte (haploid) is dominant in bryophytes, smaller in ferns, minimal in gymnosperms/angiosperms; sporophyte (diploid) becomes dominant over time.

Front: Name the 7 major groups of land plants

Back: Bryophytes (liverworts, mosses, hornworts), Lycophytes, Pterophytes (ferns, whisk ferns, horsetails), Gymnosperms, Angiosperms.

Front: What adaptations allow most land plants to survive on land?

Back: Cuticle, stomata, vascular tissue, roots, seeds, alternation of generations.

Front: Bryophytes

Back: Nontracheophytes; lack true vascular tissue; includes mosses, liverworts, hornworts.

Front: What is the role of mycorrhizae in plants?

Back: Symbiotic fungi that enhance water and nutrient absorption.

Front: Liverwort reproduction

Back: Can reproduce sexually via gametophytes and asexually via gemmae cups.

Front: Moss life cycle

Back: Dominant gametophyte produces gametes; fertilization forms sporophyte which releases spores.

Front: Hornworts

Back: Sporophyte grows from gametophyte; cells contain a single large chloroplast.

Front: Cooksonia

Back: Earliest known vascular plant; simple branching sporophyte, no leaves or roots.

Front: Name the 3 clades of vascular plants

Back: Lycophytes, Pterophytes, Seed plants.

Front: Tracheophytes vs Bryophytes

Back: Tracheophytes have vascular tissue (xylem/phloem); bryophytes do not.

Front: Origin of leaves: Lycophylls vs Euphylls

Back: Lycophylls = single vein leaves from stem enations; Euphylls = multiple veins from branch fusion.

Front: Benefits of seeds

Back: Protect embryo, provide nutrition, aid dispersal.

Front: Benefits of fruits in flowering plants

Back: Protect seeds, aid in dispersal via animals, wind, or water.

Front: Fern life cycle

Back: Dominant sporophyte, small independent gametophyte; spores grow into gametophyte.

Front: Whisk fern characteristics

Back: Simplified vascular system; homosporous; gametophyte often subterranean.

Front: Horsetails

Back: Jointed stems, silica in tissues; homosporous; sporophyte dominant.

Front: Club mosses (Lycophytes) reproduction

Back: Produce spores in strobili; heterosporous in some species.

Front: What is a seed?

Back: A seed contains an embryo, stored food, and a protective coat; allows survival and dispersal.

Front: Male and female gametophytes in seed plants

Back: Male = pollen grain; Female = ovule inside ovary.

Front: Name the 5 clades of extant seed plants

Back: Coniferophyta, Cycadophyta, Gnetophyta, Ginkgophyta, Anthophyta (angiosperms).

Front: How do seed plants differ from seedless plants in spore production?

Back: Seed plants are heterosporous; seedless plants can be homosporous.