Unit 1 Diversity of Living Things

Flashcards based on lecture notes covering key biology terms, concepts, and sample questions related to classification, kingdoms, and microorganisms.

What is binomial nomenclature?

A two-part Latin naming system [genus + species] developed by Carl Linnaeus for universally identifying species.

What is biodiversity?

The variety of living organisms, including genetic, species, and ecosystem diversity.

What are unicellular organisms?

Organisms made of a single cell (e.g. bacteria, some protists).

What are multicellular organisms?

Organisms made of more than one cell (e.g. plants, animals).

Who is Carl Linnaeus?

Scientist who developed binomial nomenclature.

What is a cotyledon?

A seed leaf in plant embryos; used to distinguish monocots (1 cotyledon) and dicots (2 cotyledons).

What is a monocot?

Flowering plants with one cotyledon, parallel veins, and scattered vascular bundles.

What is a dicot?

Plants with two cotyledons, net-like veins, and vascular bundles in a ring.

What is the lytic cycle?

Viral replication process where the virus destroys the host cell after making many copies.

What is the lysogenic cycle?

Viral DNA integrates into the host genome and stays dormant before entering the lytic cycle.

What is taxonomy?

The science of classifying organisms.

What is phylogeny?

The evolutionary history of a species or group of organisms.

What is symmetry?

Body structure can be radial or bilateral (as seen in animals).

What is an autotroph?

Organisms that make their own food (e.g. plants, some bacteria).

What is an angiosperm?

Flowering plants with seeds enclosed in fruit.

What is a gymnosperm?

Plants with "naked" seeds not enclosed in fruit (e.g. pine trees).

What are prokaryotes?

Cells without a nucleus or membrane-bound organelles (e.g. Bacteria, Archaea).

What are eukaryotes?

Cells with a true nucleus and organelles (e.g. Plants, Animals, Fungi, Protists).

What is a virus?

A non-living infectious agent made of DNA/RNA and a protein coat, requires a host to replicate.

What is a bacteriophage?

A type of virus that infects bacteria.

How is a species defined?

Defined by biological (can interbreed), morphological (physical features), and phylogenetic (evolutionary history) concepts.

What is a heterotroph?

Organisms that must consume others for food (e.g. animals, fungi).

How are bacteria and viruses harmful and helpful?

Harmful: Bacteria cause diseases like pneumonia and food poisoning. Viruses cause illnesses like the flu and COVID-19. Helpful: Bacteria decompose waste, fix nitrogen, and help produce oxygen (e.g. cyanobacteria). Viruses are used in gene therapy and vaccines.

What are the taxonomic divisions?

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

What are the 3 species definitions and when are they used?

Morphological: Based on physical traits, used when reproduction data is unavailable (e.g. fossils). Biological: Based on ability to interbreed, used for living sexually reproducing species. Phylogenetic: Based on genetic/evolutionary history, used in modern genetics.

Give 3 facts, the cell type, and examples for each of the following kingdoms: Animalia, Plantae, Protista, Archaea, Bacteria, Fungi

Animalia: Eukaryotic, Multicellular, heterotrophic, mobile. Plantae: Eukaryotic, Autotrophic, cell walls with cellulose, multicellular. Protista: Eukaryotic, Mostly unicellular, live in water, varied nutrition. Archaea: Prokaryotic, Extremophiles, no peptidoglycan, anaerobic. Bacteria: Prokaryotic, Unicellular, peptidoglycan walls, mesophiles. Fungi: Eukaryotic, Heterotrophs, cell walls with chitin, decomposers.

What is the structure of a prokaryote?

No nucleus, single chromosome, plasmids, ribosomes, cell membrane and wall.

What are methods of bacterial reproduction?

Binary fission (asexual). Conjugation (plasmid DNA exchange). Endospore formation (for survival, not reproduction).

What is an endospore?

A tough, dormant structure formed by some bacteria (not archaea) to survive harsh conditions. It protects DNA until conditions improve.

What are the 3 protist groups?

Animal-like (protozoans): move via cilia, flagella, or pseudopods (e.g. amoeba, paramecium). Plant-like (phytoplankton): photosynthesize, contain chloroplasts (e.g. diatoms, dinoflagellates). Fungus-like: absorb nutrients, form spores (e.g. slime molds).

How are fungi different from plants? How do they get nutrients?

Fungi have chitin in their cell walls, not cellulose; they are heterotrophs, not autotrophs. Fungi digest externally then absorb nutrients. Types include parasitic, mutualistic, predatory, and saprobial fungi.