Biology II - Exam 2

describe hyphae

secrete enzymes to break down organic matter, absorb the released nutrients

features of fungi

multicellular, absorptive heterotrophs, haploid dominant, earliest colonizers of land

three ecological roles of fungi

decomposers, parasitic, mutualistic

break down and absorb nutrients from nonliving organic material

decomposers

absorb nutrients from living host

parasitic

absorb nutrients from hosts and reciprocate with actions that benefit the host

mutualistic

tiny filaments that make up the fungal body

hyphae

makes up cell walls of fungi

chitin

two types of hyphae

septate, coenocytic

network of fungal hyphae that infiltrate a food source

mycelium

specialized hyphae that penetrate plant cell walls, but not the cell membrane

arbuscules

reproductive structures of many fungi

mushrooms

how fungi reproduction is carried out (sexual or asexual)

spores

stages of sexual reproduction of fungi

plasmogamy, heterokaryotic stage, karyogamy, meiosis, germination

fusion of protoplasm from two parent mycelia

plasmogamy

fusion of nuclei, usually delayed

karyogamy

stages of asexual reproduction of fungi

spore-producing structures, germination

sexual signalling molecules used to communicate mating type

pheromones

how single-celled yeasts reproduce

budding

functions of chytrids

decomposers, parasites, mutualists

phylum responsible for the decline of amphibians

phylum chytridiomycota

often called sac fungi

ascomycetes

fruiting bodies produced by acomycetes during the sexual stage

ascocarps

mushrooms, puff balls, shelf fungi

basidiomycetes

functions of basidiomycetes

rusts, smuts, mutualists, decomposition of wood

cells divided by walls, organelles can still move from cell to cell

septate fungi

hundreds or thousands of nuclei in a continuous cytoplasmic mass

coenocytic fungi

functions of ascomycetes

pathogens, decomposers, symbionts

symbiotic associations between photosynthetic organisms and fungi

lichens

mutually beneficial relationships between fungi and plant roots

mycorrhizae

nutrition mode of animals

mulicellular heterotrophs

used for structural support in animal cells

collagen

cells only within animals

muscle, nerve

characteristics of animal reproduction

usually sexual, diploid dominant

order of animal development

egg and sperm, fertilization, cleavage, blastula, gastrula

sexually immature form of an animal that is morphologically distinct from the adult

larva

developmental transition from a larva into an adult

metamorphosis

sets of DNA sequences that are found within developmental genes that regulate the expression of other genes

homeoboxes

control the placement of body parts

Hox genes

symmetrical no matter which way you cut it, tends to be sessile or planktonic animals

radial symmetry

symmetrical when cut down the middle, more active animals with a central nervous system

bilateral symmetry

the germ layer covering the embryo’s surface

ectoderm

the innermost germ layer and lines the archenteron

endoderm

the developing digestive tube

archenteron

animals that only have ectoderm and endoderm

diploblastic

animals that have a medial layer called the mesoderm

triploblastic

a true body cavity derived from the mesoderm

coelom

animals that possess a true coelom

coelomates

cleavage of a protosome

spiral and determinate

fate of blastopore in a protosome

develops mouth

cleavage of a deuterosome

radial and indeterminate

fate of blastospore in a deuterosome

develops anus

animals that lack a backbone

invertebrates

nine invertebrate phyla

porifera, cnidaria, echinodermata, chordata, platyhelminthes, mollusca, annelida, nematoda, anthropoda

phylum porifera

sponges, sequential hermaphrodites, sessile

body parts of porifera

choanocytes, mesohyl, amoebocytes

flagellated collar cells, engulf bacteria and food particles by phagocytosis

choanocytes

gelatinous region separating two layers of cells

mesohyl

cells within the mesohyl that digest food, transport nutrients, and make skeletal fibers

amoebocytes

zygotes of porifera

develop into flagellated, swimming larva that eventually settle and become sessile adults

phylum cnidaria

sea anemones, jellies, coral, hydra

phylum porifera body plan

asymmetrical, no true tissues

phylum cnidaria body plan

radial symmetry, diploblastic, no body cavity BUT gastrovascular cavity

two forms of cnidaria

polyps, medusas

sessile, adhere to substrate by the end opposite the mouth

polyps

motile, free-swimming, bell-shaped body with the mouth on the underside

medusas

central digestive compartment in a two-layered sac

gastrovascular cavity

phylum cnidaria body parts

cnidocytes, nematocysts

unique cells in tentacles used in defense and prey capture

cnidocytes

specialized organelles within cnidocytes that eject a stinging thread

nematocysts

categories of bilateria

protostomes, deuterostomes

categories of protostomes

lophotrochozoa, ecdysozoa

phyla of lophotrochozoa

platyhelminthes, mollusca, annelida

platyhelminthes

flatworms

platyhelminthes body plan

bilateral symmetry, triploblastic, acoelomate, protostome

three types of platyhelminthes

planarians, flukes (trematodes), tapeworms

planarians

non-parasitic, slightly complex and centralized nervous system, hermaphrodites

flukes (trematodes)

parasites, complex alternating life cycles, multiple hosts

tapeworms

parasitic, absorb nutrients from the intestines of the host

mollusca

land snail, octopus, clam, chiton

mollusca body plan

bilateral symmetry, triploblastic, coelomates, protostomes

mollusca body parts

muscular foot, visceral mass, mantle, mantle cavity, radula

usually used for movement in mollusca

muscular foot

contains most of the internal organs of mollusca

visceral mass

a fold of tissue draping over the visceral mass that secretes the shell

mantle

houses gills, anus, and excretory pores

mantle cavity

used to scrape up food in mollusca

radula

types of mollusca

gastropods, bivalves, cephalopods

gastropods

snails, slugs, single spiraled shell, move using cilia or rippling feet

bivalves examples

clams, oysters, mussels, scallops

bivalves

two shells with a hinge called adductor muscles, some have eyes, gills for suspension feeding and gas exchange, most are sedentary

cephalopods examples

squid, octopus, chambered nautilus

cephalopods

predators with beak-like jaws, muscular excurrent siphon, closed circulatory system, complex brain

modified foot as part of tentacles in cephalopods

muscular excurrent siphon

annelida body plan

bilateral symmetry, triploblastic, coelomate, protostome

categories of annelida

leeches, earthworms

leeches

most are parasites, some secrete anesthetic to prevent detection

earthworms

eat through soil, hermaphrodites, can reproduce by fragmentation and regeneration

animals with a cuticle

ecdysozoans

shedding/molting of the outer cuticle

ecdysis