BIO 1B - Organismal Biology

prokaryote

unicellular organism that lacks a nucleus or any other membrane-bound organelle, usually has DNA contained in a circular plasmid

eukaryote

cells w linear chromosomal DNA packed into nucleus, has membrane-bound organelles

anaerobe

organisms that work without and must occur in the absence of oxygen

aerobe

organisms that requires oxygen for growth

photoautotroph

organisms that use light energy and CO2 to make their own food

photoheterotroph

organisms that use light energy and rely on carbon from other sources like organic material (not carbon dioxide)

chemoautotroph

organisms that use energy from oxidation of inorganic chemicals and solely rely on CO2 for carbon

chemoheterotroph

organisms that use energy from oxidation of inorganic chemicals and rely on carbon synthesized by other organisms

plastid

one of a group of related organelles in plant cells that are involved in the storage of starches, fats, proteins, and pigments. photosynthetic varieties are chloroplasts

plasmid

extrachromosomal, covalently closed, circular DNA molecule that may only contain one or a few genes; common in prokaryotes

binary fission

process of prokaryotic cell division

stromatolite

a sedimentary structure formed when minerals are precipitated out of water by prokaryotes in a microbial mat

cyanobacteria

bacteria that evolved from early phototrophs and oxygenated the atmosphere; also known as blue-green algae

endosymbiosis

engulfment of one cell within another such that the engulfed cell survives, and both cells benefit; the process responsible for the evolution of mitochondria and chloroplasts in eukaryotes

microbiome

refers to all microorganisms found in a given well-defined habitat, establish through horizontal and vertical transmission

horizontal transmission

one of the ways in which microbiomes establish, when microorganisms enter the host from the environment

vertical transmission

one of the ways in which microbiomes establish, when microorganisms are passed down directly from parent to offspring

heterocyst

specialized nitrogen-fixing cells formed during nitrogen starvation by some filamentous cyanobacteria, it allows for spatial separation of anaerobic N fixation and aerobic photosynthesis and sharing of the products

metabolite cross-feeding

an interaction betwen bacterial strains in which molecules made by the metabolism of one strain are futher metabolized by another strain, example of microbial mutualism

biofilm

a surface coating colony of one or more species of prokaryotes that engage in metabolic cooperation

quorum sensing

method of cellular communication used by bacteria that informs them of the abundance of similar (or different) bacteria in the environment based on the concentration of autoinducer molecules

autoinducer

signaling molecules secreted by bacteria to communicate with other bacteria of the same kind.

examples of biofilms

stromatolites, mouth plaque, biofilm can physically inhibit the delivery of antibiotics

phagocytosis

the process by which a cell takes in large particles, such as other cells or relatively large particles by engulfing the particle with the cell membrane and brings it into the cell in a vesicle

absorptive nutrition

a type of digestion used by fungi where they secrete enzymes to digest food outside of their bodies and absorb the nutrients

hyphae

the filaments of multicellular fungi

mycelium

a network of hyphae

indeterminate growth

used to describe how the growth of mycelial networks do not have a defined end structure and will continue growing

arbuscular mycorrhizal fungi

specialized hyphae that penetrate root cells and create structures called arbuscules that allow for mutualistic symbiosis with most terrestrial plants

ectomycorrhizal fungi

specialized hyphae that form nets around the whole root of a plant and the cell surfaces within the root but do not enter the cells, allowing for mutualistic symbiosis to occur

spores

single haploid cells that are capable of growing into an adult organism

sporogenesis

the process of spore formation

gametogenesis

the process of gamete formation

meiosis

a process of cell division that results in 4 haploid cells

fertilization

union of haploid gametes to produce a diploid zygote

sporophyte

diploid organism that produces spores by meiosis

gametophyte

haploid organism that produces gametes by mitosis

fruiting body

the part of a fungus that protrudes from the ground, often as an adaption to spread spores further

basidiomycete

club and shelf fungi, they produce the familar mushrooms with gills underneath

basidium

the club-like cell that lines the gills of the basidiocarp where fertilization of the fungi finsihes

basidiocarp

the fruiting body of basidiomycetes, aka the mushroom

plasmogamy

when the cytoplasm of two haploid cells fuse, leading to a dikaryotic stage where two haploid nuclei coexist in a single cell

heterokaryon

a mycelium with two distinct haploid nuclei types in each cell

karyogamy

when two haploid nuclei in a cell fuse to form a diploid zygote nucleus

mycosis

fungal infection

monophyletic group

a clade, a group of organisms that share a single ancestor

ecological / functional group

a set of taxa that share alike characteristics, often in the same community

primary endosymbiosis

the first internalization of a prokaryote (ex. cyanobacteria) by an ancestral eukaryotic cell; plastids of this origin are surrounded by two membranes

secondary endosymbiosis

when red or green alga (being eukaryotes that already underwent primary endosymbiosis) is absorbed by another eukaryote; plastids of this origin are surrounded by three or more membranes,

haplodiplontic life cycle

the life cycle found in all plants where an organism alternates generations between haploid and diploid multicellular stages

dinoflagellates

a type of unicellular algae that has two flagella that make it spin, produce toxins when in blooms that is linked to red tides and conducts symbiosis of corals with zooxanthellae

diatoms

a type of unicellular algae that has unique glass-like cell walls made of silica and responsible for 25% of global NPP, accumulates into deposits of diatomaceous earth

brown algae

can be unicellular or multicellular, consist of marine algae including kelps

red algae

can be unicellular or multicellular, can come in diverse colors/forms but tends to be red because it absorbs blue light which is capable of penetrating to lower ocean depth

green algae

can be unicellular or multicellular, are close to the plant kingdom and are found in freshwater and seawater

phycocolloid

a polysaccharide compound produced by algal cell walls to prevent dessication

lichen

the close association of a fungus with a photosynthetic alga or bacterium that benefits both partners

photobiont

the phototrophic alga or cyanobacteria part of a lichen

mycobiont

the heterotropic fungus part of a lichen

soredia

clusters of algal cells and mycelia that allow lichens to propagate by breaking off

“seed-free” plants

terrestrial plants made up of lycophytes and monilophytes (seedless and vascular) and bryophytes (nonvascular)

bryophyte

nonvascular seed-free plants that were the first terrestrial plants, made up of liverworts, mosses, and hornwort

dessication

when plants are drying up

phyllids

thin leaf-like growths that absorb water through direct contact w/ the ground or trapped moisture (not leaves)

rhizoids

long tubular single cell or filaments that do some water/nutrient uptake but mainly function to anchor plants (not roots); also associate with arbuscular mycorrhizal fungi

gametangia

multicellular protective tissues where gametes form

archegonia

gametangia that produce eggs

antheridia

gametangia that produce sperm

embryo

the zygote (fertilized egg) that is retained in the archegonium and develops while dependent on the parent plant for nutrition

cuticle

waxy covering on the outside of the leaf and stem that prevents the loss of water

sporangia

the container in which spores are formed

sporopollenin

a polymer that prevents dessication of charophyte zygotes and to make plant spores resistant and capable of dispersal by air

peat

partially decayed organic material found in huge, boggy wetlands known as peatlands, contains lots of carbon and mainly made of Sphagnum (peat moss)

lycophyte

the earliest group of seedless vascular plants that includes club moss, spike moss, and quillwort; its leaves are microphylls

monilophyte

seedless vascular plants that include ferns, horsetails, and whisk ferns, it has leaves that are megaphylls

microphyll

leaves that are small in size and has a simple vascular system with a single unbranched vein

megaphyll

leaves that are larger with a pattern of branching veins

sporophyll

leaves that form sporangia

sorus

a clustered group of sporangia (plural: sori)

carboniferous period

a period of time when plants greatly expanded the CO2 sink into marine rocks (root acids wore down continental rock, allowing for CO2 to react with Ca and Mg and form minerals that were deposited into marine rocks) and into peatlands (trees that died in the boggy soils of the carboniferous decayed slowly and becaome peal, and then become coal over millions of years)

azolla

a very small aquatic fern that forms a symbiotic association with nitrogen-fixing cyanobacteria and can increase its biomass very very fast

the azolla event

during a time when the Artic ocean was enclosed, the water became turbid and a thin freshwater layer developed on top where azolla populated and for almost a million years dead azolla mats accumulated as stagnant sediment that drew CO2 out of the atmosphere and sunk it to the ocean floor

heterospory

the quality of making 2 types of spores each from a different sporangium (megaspores and microspores)

gymnosperm

“naked seed” produce seeds and pollen in cones, ex: gnetophytes, cycads, gingko, conifers

seed

structure containing the embryo, storage tissue, and protective coat

pollen cone

male gymnosperm reproductive structure that makes pollen (microsporangiate, 2n)

ovulate cone

female gymnosperm reproductive structures that have 2 ovules per scale (megasporangiate, 2n)

scale

a cone’s modified leaves with sporangia (sporophylls, 2n)

megaspore

female spore that is made from megasporocytes in the megasporangium within the ovule, becomes the megagametophyte (n)

megasporangium

the tissue within the ovule where meiosis gives rise to megaspores (2n)

microspore

male spore that is made in the microsporangia and become pollen grains (n)

microsporangium

the tissue within the stamen or the scales of a pollen cone that gives rise to microspores by meiosis

pollen grain

structure containing the male gametophyte of the plant (n); made up of 2 cells, the pollen tube cell and the generative cell that becomes sperm; encased in sporopollenin

pollen tube

extension from the pollen grain that delivers sperm to the egg cell

ovule

megasporangium surrounded by the protective structure that will become the seed coat

integument

layer of sporophyte tissue that surrounds the megasporangium, and later, the embryo (2n)

seed coat

the protective coat that protects the embryo, comes from the hardened integument

pollination

the transfer of pollen to the part of a seed plant containing the ovules

angiosperm

seeded, vascular terrestrial plants that is the most dominant plant group due to its evolution of flowers and fruit

determinate growth

growth that ceases when a plant part reaches a predetermined size, happens in leaves and flowers