COA305: Exam II

Eukaryotes

Eukaryotes

organism with membrane bound organelles, nucelus, and a cytoskeleton

Protists

a primarily unicellular organism that is not an animal, plant, or fungus

does not undergo tissue formation through embryological layering

heterotrophic and autotrophic

Plankton

organisms living in the water column, too small to swim counter to typical ocean currents

Phytoplankton

photosynthetic plankton

usually protists

diatoms, dinoflagellates

Zooplankton

heterotrophic plankton

typically larval animals and copepods

Meroplankton

Zooplankton that only spend a portion of their life cycle as plankton, typically larvae

Holoplankton

zooplankton spend entire life cycle as plankton

Diatoms

Photosynthetic protist that occurs singly or in chain formation

→ 2-200 microm

→ encased in silica shell w/ two valves

→ radially symmetrical

Size reduction

in diatoms, binary fission occurs when one diatom is split and half, and one valve foes to each offspring. This leads to gradual _____

→ smallest frustule will reproduce sexually

Dinoflagellate

species of photosynthetic protists that secrete organic test (exoskeleton) and have two flagellae

→ 2-200 microm

→ photosynthetic or heterotrophic

→ abudannt in tropics, mid-summer

→ some with life history stages as benthic cysts

Dinoflagellate

red tides are caused by this protist

Coccolithophores

unicellular, photosynthetic protist

→ covered in calcium carbonate plates(coccoliths)

-> spherical

→ 2-29 microm

Silicoflagelaltes

unicellular biflagelalte protist

→ internal skeleton of silcia scales

→ found in open ocean, often in Antartic

Foraminifera

type of heterotrophic protist that secretes the skeleton of calcium carbonate

→ ornamentation

→ uses contractile pseudopodia that traps food particles

→ size ~ 1mm to a few mm

Radiolaria

heterotrophic protists with a skeleton of silica

→ occurs singly or in colonies

→ ~ 50 to a few mm

→ membrane sperates interior cell from exterior cytoplasm which streams out

Ciliates

hetetropthic protists that feed on bacteria, smaller plankton

→ commonly mixotrophic

→ elongate, covered in rows of cilia

→ 50 micro m - 1mm

microalgae

single-celled photosynthetic protists

diatoms, dinoflagellates

examples of microalgae

macroalgaes

large photosynthetic algaes

Seaweeds

colonial macroalgaes apart of kingdom protista

usually connected to substratum

take up ntureitns from surrodning waters; no vascular system

thallus

individual seaweed

Holdfast

anchors the thallus to substrate

→ usually a simple disc with many hair like sturcutes

→ some with root like structures

Stipe

tubular, flexible stem of the thallus

lifts fronds off the water

Frond

broad, flat structure on seaweed specialized for light capture; both sides identical

Pneumatocysts

gas filled floats that keep fronds on seaweeds suspended in the water column

spores

type of reproductive cell used in seaweed reproduction that is cpaable of developing into a new indvidual without fusing with another cell

water

seaweeds lack complex root systems and vascular system, resulting in direct nutrient uptake from

fronds

photosynthesis in seaweed mainly occurs in the

photosynthesis

seaweeds gain energy from

Chlorophyta

green algae

→ photosynthetic pigments: chlorophylls a and b (simialr to plants)

→ storage: starch

ex: codium, ulva

starch

type of storage in chlorophyta

Phaeophyta

brown algae

→ pigments: chlorphyll a and c

→ storage: lamarin

→ ex: Gracilaria

Gracilaria

red corraline algae

Rhodophyta

red algae

→ pigments: chlorphyll a and c, fucozanthin

→ storage: lamiarian, mannitol

ex: Kelp, Sargassum

floridian starch

storage in rhodophyta

Lamarin, mannitol

storage in Phaeophyta

Sargassum

Example of Rhodophyta

Spherical symmetry

any plane can pass through the center divides the organism into like- halves

ex: radiolarian

Radial Symmetry

type of symmetry where an organism can be divided along its main axis

Bilateral Symmetry

type of symmetry where there is only way to divide an organism

→ results in left and right sides

Diploblastic

embryonic tussue layer with just the endoderm and ectoderm

Triploblastic

embryonic tissue layer with endoderm, mesoderm, and ectoderm

allows for the development of body cavities (coelom)

Coelom

fluid filled cavity between body wall and digestive tube

sleaze

group of sponges

Choanocytes

collar, flagelalted cells located in the atrium of a sponge

→ circulate water through canals in the sponge

Ostia

Inlet holes in the sponge that accept water

Atrium

Central Cavity of the sponge

Osculum

the exit hole of the sponge

Pinacocyte

platter cell. Forms the skinlike cellular pavement over the surface of the sponge 

Spicule

• structural element made up of carbonate or silicon dioxide 

  • Can have amoebocyte cells on the outside of spicules 

  • secreted by sclerocyte

Amoeboecyte

Progenitor cells; totipotent and phagocytic in a sponge

porocyte

type of pinacocyte that forms the ostia, miniature sphincater valves present

Pinacoderm, mesohyl, Choanoderm

layers of the body wall in sponges

Pinacoderm

layer of the sponge body well with pinacocytes

→ exo: covers outersurface of sponge

→ endo: lines incurrent and excurrent canals

Mesophyl

conenctive tissue of the sponge body wall w/ psiracles and ameboycytes

Choanoderm

artial lining and lining of choanocyte chmabers w/ choanocytes

Asconoid

sponge body plan

• Water plans glow in through many ostia and out through the osculum 

• Simple 

• For sponges <1mm in diameter

• cylindrical bodies

Syconoid

• More complex sponge 

• Folded body wall to create more surface area 

• Reduces atrial volume 

• Increases the SA of choanocyte chambers 

• 1-10 cm

Leuconoid

• A complex network of water vessels in a solid spongy body 

• No big atrium 

• Spherical choanocyte chambers at the intersection of incurrent and excurrent canals 

• Multiple oscula 

• >10cm 

• Spicules covered with spongin

Spicules

endoskeleton component that can be siliceous(spongin) or calcaerous (Calcarea)

secreted by sclrenocytes→ begin as a membrane and grow into the spicule shape

Spongin

organic material of demosponge, compressible

found in spicules secreting SiO2

Sponge Food Intake

• H2O is pumped into an incurrent canal-> enters into a chonocyte chamber where particles <5 micrometers are phagocytized-> flow into the excurrent canal and through the osculum st 7mm/s

  • Incurrent canals: phagocytize food particles 5-50 micrometers

  • Exopinacoderm: >50 micrometers

• Undesirable inorganic material  is grabbed by archeocytes, put in a phagocyte, and released through the osculum 

phagocytosis

digestion occurs in sponges via

Calcaera

calcerous sponges with calcium and carbonate spicules

Hexactinnellida

glass sponges

Demospongiae

silicious spicules or organic skeleton sponges

Heteroscelopmorpha

sponges with an absent skeleton; composed of very small siliceous spicules if present

diffusion

sponges primarily intake gas through _____
→ ventilation of all body regions occurs within 1mm of all cells

→ small enough to carry out this process

fragmentation, budding

types of clonal reproduction in sponges

budding

type of clonal reproduction in sponges

where one small piece of the parent cell forms and buds off to form its own independent stage

Fragmentation

type of clonal reproduction in sponges where a broken piece can regrow; common in leucoid sponges

choanocytes

sperm arises from this type of cell in sponges

Broadcast spawning

occurs in oviparous sponge species where sperm and sometiems the egg is released into the enviromentenvironment

Sexual reproduction in sponges

hermaphrodites

sperm arises from choanocytes and lacks an acrosome

sperm nucleus is trapped by choanocytes and a transfer of choanocytes gives up its sperm to the egg via phagocytosis

→ viviparous and oviparous species

5-50 microm

incurrent canals in sponges phagocytize food particles this size

>50 microm

exopinacoderm phagocytizes food particles this size

Comb Rows

string along the aboral portion of ctneophores that contain rows of ctenes

ctenes

rows of cillia fused together, found on ctenophore combs

Ctenophora

largest animal to use cillia for locmotion

Aboral organ

organ containing a statocyst, located on the aboral end of the ctenophores body

Statocyst

strucute used for gravity, balance and direction sense of acceleration

→ Statolith, ciliary dome, balance

Statolith

a pouch of sac lined with mechanosensory hair cells

Nerve Net

nervous system in ctenophores , no concnetration of nerves, spread long the entire body

Mnemiopsis leidyi

sea walnut

common species of ctenophore in the GoM and Atlantic

Invasive to the Black Sea, Caspian, North, and Baltic due to large consumption of zooplankton and fish larvae

Direct

the development of the ctenophore from egg to juvenile, no larval stage

gastrodermis

body wall layer in ctenophores on the inner body surface

Water gel

thin layer between the Epidermis and Gastrodermis on the ctenophore; very few cells. Facilitiates diffusion through skin

Epidermis

outer layer of cells on the ctenophore that faciliates diffusion of gases

Tenitlla

small, adhesvie granules on tentacles of ctenophores that hook onto prey

oral-aboral axis

main body axis of the ctenophore that indiciates radial symmetry

mouth-forward

direction that ctenophores swim

mouth

tentacles location on ctenophores

rudimentary anal pores

digestice system in ctenophores

Ctenophore Locomotion

use cilary movement; rhymtic beat of ctenes move organism in the mouthward direction

Coelenteron

a gut like cavity in phlyum cnidaria that is surronded by the body wall; ringed by tentacles

Polyp

Body form of Cnidarians (Hyroids, corals, and anemones)

witth a pedal disc, column and oral disc and manubrium at top

manubrium

in cnidarina, this is an protubernace of the oral disc with the mouth attached to it

Medusae

body form of cndarias with no attachment to substrates

tentacles around the margin of a bell and around mouth

oral arms produtude from mouth

mouth located at tip of manubirum

swimming: bell propulsion

Mesoglea

gelatinous extracellular matrix in cnidarians

diffusion

respiration in cnidarians is through ______ as all metabolically active tissue is in close contact with the water