Biology II Test 3 & 4

mycologist

biologists who study fungi

chitin

polysaccharide; what fungi cell walls are made of

mychorrhizae

fungi and roots growing together; mutualism

endophytes

organisms that live between and within plant cells

Ectomycorrhizal Fungi (EMF)

dense network of hyphae that cover a plant’s roots and extend into the soil; penetrate decaying material and release peptidases the cleave proteins and release amino acids

Arbuscular Mycorrhizal Fungi (AMF)

grow inside root cell walls; form a pipeline extending from inside plant roots into the soil well beyond the root

lichen

symbiotic association between a photosynthetic microorganism (green algae or cyanobacteria) and a fungus (often an ascomycete); millions of photosynthetic cells are held in a mass of fungal hyphae

foliose

leaflike lichen

crustose

encrusting lichen

fruticose

shrublike lichen

Cordyceps

genus of ascomycete fungi that parasitize insects

Saprophytes

fungi that make a living by digesting dead plant material

yeasts

single-celled form of funguss

mycelia

multicellular filamentous form of fungi

septa

divide cells in fungal hyphae; often have pores that allow for cell-to-cell movement

coenocytic fungi

lack septa; have a continuous cytoplasmic mass with hundreds or thousands of nuclei

plasmogamy

union of cytoplasm from two parent mycelia

heterokaryon

two nuclei coexist in mycelium

dikaryotic

haploid nuclei pair off two to a cell

karyogamy

nuclear fusion; produce diploid phase that are short-lived and undergoes meiosis to produce haploid

conidia

asexual spores

zygosporangia

spore-producing structures when hyphae are yoked

Basidia

specialized club-like cells that form at the ends of hyphae; produce four spores

asci

reproductive sac-like cells at ends of hyphae; produces eight spores

Microsporidia

single-celled; parasitic; distinguished by polar tube

polar tube

shoots out from microsporidian, penetrates membrane of host cell, and acts as conduit for the contents of microsporidian cell to enter host cell

Chytrids

largely aquatic; enzymes digest cellulose; have flagellated spores and gametes

zygomycetes

soil-dwellers; produce thick-walled zygosporangia

glomeromycetes

All members except one comprise AMF

Basidiomycetes

reproduce using basidia; mushrooms are cultivated or collected for food; many decompose wood (lignin peroxidase); fairy rings

ascomycetes

asci for reproduction; yeasts; lichensa

ascocarp

fruiting body of ascomycetes

basidiocarp

fruiting body of basidiomycete

extracellular digestion

digestion takes place outside or organism; simple compounds from enzymatic action absorbed by hyphae

lignin

extremely strong, complex polymer found in secondary cell walls of plant vascular tissues where it provides structural support

cellulose

polymer of glucose found in the primary and secondary cell walls of plants

cellulases

enzymes that break down cellulose

tissues

groups of similar cells that act as a functional unit; collections of specialized cells isolated from other tissues by membranous layers

cleavage

rapid cell division

blastula

multicellular; hollow

gastrulation

blastula become gastrula

gastrula

different layers of embryonic tissues

Hox genes

genes that regulate development

choanoflagellates

group of protists that is closest living relative to animals

benthic

live at the bottom of aquatic environmentss

sessile

adults live permanently attached to a substrate rather than moving freely

Cambrian explosion

535-525 mya; earliest appearance of many major groups of living animals

bilaterians

bilaterally symmetrical; complete digestive tract; one-way digestive system

body plan

set of morphological and developmental traits

ectoderm

germ layer covering embryo’s surface; gives rise to body covering and nervous system

endoderm

innermost germ layer; lines digestive tube, gut and other digestive organs

mesoderm

middle germ layer; circulatory system, muscle, and internal structures

diploblastic

endoderm and exoderm

triploblastic

endoderm, exoderm and mesoderm

coelom

true body cavity; derived of mesoderm; completely lines by mesoderm

protostome

first mouth; blastopore becomes mouth; spiral and determinate cleavage

deuterostrom

second mouth; blastopore becomes anus and second hole becomes mouth; radial and indeterminate cleavage

blastopore

forms during gastrulation; connects archenteron to the exterior of the gastrula

cephalization

concentration of sensory organs in the head region

suspension/filter feeders

capture food by filtering out particles suspended in water or air

deposit feeders

digest living or dead organic matter in the sediments

fluid feeders

suck or mop up liquids like nectar, plant sap, blood, or fruit juice

mass feeders

ingest chunks of food

parthenogenesis

females produce diploid eggs that can mature into adults without being fertilized

viviparous

retain embryos in female’s body during development; give birth to live young

oviparous

lay eggs outside to develop independently of mother; embryos nourished by yolk within the egg

ovoviviparous

female retains eggs inside her body during early development; growing embryos are nourished by yolk inside egg a not by nutrients directly from mother; females give birth to well-developed young

porifera

sponges; sedentary and live in marine or fresh water; feed with choanocytes; filter feeders

spicules

stiff spikes of silica or calcium carbonates that proved structural support to ECM

mesohyl

gelatinous noncellular layer between two cell layers containing spicule

hermaphrodites

each individual produces both egg and sperm

cnetophora

comb jellies; planktonic and predatory; coloblasts

coloblasts

specialized sticky cells for trapping prey; cnetophores

cnidaria

use cnidocytes for capturing prey; medusa or polyps; tentacles; diploblastic; gastrovascular cavity and single opening for mouth and anus

cnidocytes

cells that eject a barbed structure that may contain toxins into prey

nematocysts

specialized organelles within cnidocytes that eject a stinging thread

polyp

adheres to substrate by aboral end of body; tentacles facing up

medusa

bell-shaped body with mouth on underside; move freely

hydrazoans

medusazoans; alternate between polyp and medusa

schyphozoa

medusazoans; jellyfish

cubozoans

medusazoans; box jellies; often have highly toxic cnidocytes

anthazoans

anemones and corals; polyps

lophophore

specialized structure that rings the mouth of these animals and functions in suspension feeding

trocophores

type of larva with ring of cilia round middles that functions in sweeping and sometimes feeding

platyhelminthes

flatworms; gastrovascular cavity with one opening; finely branched; rely on diffusion

turbellaris

class of Platyhelminthes; free-living; mouth is near middle of body on ventral surface at end of pharynx

trematodes

class of platyhelminthes; parasites; sexual and asexual stages; produce surface proteins that mimic their host’s immune system and manipulate immune system

cestoda

class of platyhelminthes; tapeworms; no digestive system; absorb nutrients by diffusion across body wall; scolex and proglottids

scolex

cestoda; suckers and hooks for attaching to hosts

proglottids

units that contain sex organs and form a ribbon behind the scolex

monogenea

class of platyhelminthes; ectoparasites especially on fish

rotifers

tiny animals in freshwater, ocean or damp soil; ring of cilia around mouth; alimentary canal; parthenogenesis

alimentary canal

digestive tube with a separate mouth and anus

annelida

coelom; fully developed digestive tract; segmented body; bristle like chaetae on lobe like parapodia

polychaeta

class of annelids; numerous chaeta

oligochaetes

earthworms; deposit feeders as soil moves through alimentary canal

hirudenia

leeches; ectoparasites

hirudin

chemical that prevents blood coagulation

Mollusca

foot, visceral mass, mantle, mantle cavity, radula

foot

large muscle located at base of the animal; used in movement