Inverts Midterm

Biology

The Study of Life

zoology

The branch of biology that deals with animals and animal life

Invertebrates

97% of the animals on the planet, without a vertebral column

Prokaryote

Single celled organism without a nucleus, mitochondria, or other membrane bound organelles

Metazoa

Ingestive, heterotrophic, sexual, multicellular eukaryotes that form tissues

Ediacaran Period

worldwide invertebrate fauna; 635-541 MYA

Cambrain Explosion

541-520 MYA, rapid increase in biodiversity and abundance

Stromatolites

Layers of microbial mats, bio-accretionary structures

Primary Endosymbiosis

2.5-2 BYA, alphaproteobacterial symbiosis generates mitochondria, first eukaryotic multicellular organisms

Great Oxygenation

2.5-2 BYA, 1st mass extinction, oxygenation grants atmospheric protection

Paleozoic

270 MYA, 90% of species go extinct, increased: temperature, atmospheric CO2, decreased: pH, O2

Adaptive radiation

small bodied ‘generalist’ survivors repopulating devastated environments

monophyletic

groups/clades that include all descendants of a stem species

paraphyletic

group that has the same evolutionary orgion, but does not include all the descending groups

Polyphyletic

Composite groupings of organisms without the true biological rationale/shared biological ancestor

Apomorphy

An evolutionary innovation present in a biological lineage, but not with its ancestral group

synapomorphy

Shared apomorphy with 2 or more groups of organisms

Bacteria

No membrane enclosed organelles or nuclei; no cytoskeleton

Archaea

Anaerobic and aerobic, methane-producing organisms, no membrane enclosed organelles or nuclei, no cytoskeleton

Protista

No membrane enclosed organelles or nuclei; no cytoskeleton

Fungi

Chitinous wall around vegetative fungal cellsPl

Plantae

Unicellular, multicellular; photosynthetic

Animalia

Multicellular, heterotrophic, tissue layering eukaryotes

Specific Heat

the amount of energy required to heat a substance.

Carbonate Buffering

carbonate ions balance excess CO₂ content by re-speciating into bicarbonate and carbonic acid

Niche

a set of all the conditions of a single species in a certain environment

Fundamental Niche

complete range of environmental conditions where a species could survive, grow, and reproduce

Realized Niche

actual range of environments used by a species, part of the fundamental niche

Niche Partitioning

similar species evolve to use different resources or inhabit different parts within the same environment

Continental Shelf

0-1000 km from shore, <200 m deep, high biological productivity

Continental Edge

Rapid change in bathymetry, transition zone between shelf and slope

Abyssal Plain

region with slope of 4-6%, 200-300 m deep

Abyssal Plain

reigon with no light, >3000 m deep, productivity by chemosynthesis

Supratidal

Area above mean high tide, flooded by storms

Intertidal

dynamic area between low and high tide

Subtidal

area below low tide line, never uncovered

Neritic

Pelagic region over continental shelf

Photic

Water column with enough sunlight for photosynthesis

Aphotic

water column with not enough sunlight for photosynthesis

Disphotic

transition region between photic and aphotic zones

Bernoulli’s Principle

as the speed of a moving fluid (liquid or gas) increases, its internal pressure decreases

Reynolds Number

A dimensionless term that describes the fluid flow patterns in different physical situations; the ratio of inertial to viscous forces acting on an object within a fluid

Epifaunal

Organisms that live on top on sediment/substrate

Infaunal

Organisms that live within sediment

Interstitial

living between sand grains

Meiofauna

organisms living between sand grains

Errant

active, motile organism

Sessile

organism firmly attached to the substrate

Sedentary

Unattached/weakly attached organism

Holoplankton

Organism that remain in plankton for whole life

Meroplankton

organism that are temporarily members of plankton community

Choanocyte

Collar cell in sponge reminiscent of choanoflagellate

Cilia

shorter more abundant cell structure for movement, feeding, digestion

Flagella

longer, fewer cell structure for movement, digestion, gas exchange, reproduction

Oxygen Diffusivity

only 1 mm into tissues until fully utilizedS

Solutions to Diffusion

fold cell surface, flatten, become threadlike, or become multicellular

Embryogenesis

Cells resulting from inital division of zygote

Vitellogenesis

yolk production

zygote

Fertilized egg

blastomeres

cells resulting from initial division of zygote

holoblastic

cleavage planes pass completely through cell

meromeres

larger cells at vegetal polemic

micromeres

smaller cells at animal pole

meroblastic

cleavage planes do not pass completely through cell

Radial Cleavage

longitudinal and transverse divisions arrange blastomeres in rows

Spiral Cleavage

successive diagonal division of cells

Blastula

embryonic stage of formation preceding embryonic germ

Blastocoel

space within the blastula/primary body cavity

coeloblastula

hollow ball of cells, usually 1 cell layer thick

Steroblastula

solid ball of blastomeres

discoblastula

cap of cells at the animal pole

Coelom

true body cavity

protostome

mouth formed first during gastrulation

Deuterostome

Anus formed first during gastrulation

Ectoderm

outer layer; forms the nervous system, outer skin

Mesoderm

Middle layer; coelomic lining, circulatory system, internal support sturctures

Endoderm

inner layer; gut and other associated structures

Osmoregulator

maintains ions/ water balance independent of the environment

Osmoconformer

ion/water balance varies with the environment

Protogynous hermaphrodite

female transition to male

Protandrous hermaphrodite

male transition to female

Proprioceptor

senses orientation to environment

Georeceptor

detects the pull of gravity

Gonochoristic

having only testes or ovaries

Gastrula

embryonic stage where germ/tissue layers develop

monophyletic

groups/clades that include all descendants of a stem species

metameres

repeated sections in an annelid

Proglottids

repeated sections of tapeworms

Spicules

structural support and defense for sponges

Neoblast cells

regeneration cells in Platyhelminthes

Crystalline Style

Unique digestive structure found in bivalves and gastropods

Parapodia

appendage on the sides of many annelids

Proboscis

used to capture prey by nemertean

Retractor Muscle

retracts the proboscis

Mesenchyme

loosely organized mesodermal tissue

Peristaltic waves / undulatory swimming

movement of larger worms

stylets

nail shaped structures made of calcium phosphate

Cerebral Ganglion

longitudinal nerve cords, encircles gut or proboscis (nemertean)

Pilidium

free swimming planktotrophic larvae

Prostomium

first anterior body segment