Bio Lec Exam (terminology)

extracellular digestion

Digestion that takes place outside body cells; enzymes released to the environment break down nearby organic matter into particles the fungus can absorb (absorptive heterotrophy)

Hypha (pl. hyphae)

Any of the threadlike filaments that form the mycelium of a fungus, or of many Oomycota

Mycelium

A network of branching hyphae that constitutes the body of a multicellular fungus, or of many Oomycota.

septum (pl. septa); septate

A thin partition or cross wall that separates body segments

Chitin

A polysaccharide that contains nitrogen and is present in the cell walls of fungi and the exoskeletons of arthropods.

coenocytic

Condition in which a single cell has many nuclei.

Haustorium (pl. haustoria)

The hyphal tip of a parasitic fungus that penetrates a host plant and absorbs nutrients from it

syngamy

Union of haploid cells or nuclei from different individuals; consists of two stages separate in time (plasmogamy and karyogamy)

plasmogamy

the union of the cytoplasms of two parent mycelia

karyogamy

Fusion of two haploid nuclei to form a diploid nucleus

dikaryon (dikaryotic)

The life stage in certain fungi in which a cell contains two genetically distinct haploid nuclei

meiospore

Spore produced by meiosis; haploid.

mitospore

A spore produced asexually by mitosis; diploid

Sporangiospore

A form of asexual spore in fungi; enclosed in a sac

Conidiospores

A form of asexual spore in fungi; not enclosed by a spore-bearing sac

Zygosporangia (Zygospore)

A multinucleate, thick-walled sexual spore formed from the fusion of the cytoplasm of the mycelia of two neighboring fungi; many zygotes are formed here

gametangium

In certain plants and fungi, a cell or organ in which gametes are produced.

Mycorrhizae

Symbiotic relationship between the mycelium of a fungus and the roots of certain plants

Endomycorrhizae

A mycorrhiza in which the fungal hyphae penetrate into cells of the root.

Arbuscules

The branched hyphae of endomycorrhizae.

Ectomycorrhizae

Mycorrhizae that grow between and around the roots of trees and shrubs but do not enter root cells

fruiting body

In some fungi, a stalked, spore producing structure such as a mushroom

vegetative body

unicellular or multicellular thallus

ascus (pl. asci)

A saclike cell in ascomycetes (sac fungi) in which meiosis gives rise to haploid sexual spores (meiospores)

ascocarp

In ascomycete (sac) fungi, a reproductive body that bears or contains asci.

hymenium

fertile hyphal cell layer of the ascocarp; contains dikaryotic saclike cells called asci

Apothecium

cup-shaped ascocarp with the hymenium lining the cup and fully exposed on the outer surface

Perithecium

a "closed" flask-like ascocarp having a narrow opening, usually at the top

Cleistothecium

A completely closed ascocarp

Sporangia(um)

A multicellular organ in fungi and plants in which meiosis occurs and haploid cells develop.

Conidium (pl. conidia)

An asexual spore produced by many species of ascomycetes

basidium (pl. basidia)

A small, club-shaped structure in which sexual spores of basidiomycetes arise.

basidiocarp

A fruiting body of a basidiomycete; mushrooms are examples.

mold

Asexual, spore-producing stage of many multicellular fungi

yeast

A single-celled fungus that reproduces by budding or fission

lichen

A single vegetative body that is the result of an association between a fungus and a photosynthetic partner, often an alga.

Decomposer

A small organism, such as a bacterium or fungus, that feeds on the remains of dead organisms, breaking down complex biological molecules or structures into simpler raw materials.

radial symmetry

A body plan of organisms in which structures are arranged regularly around a central axis, like spokes radiating out from the center of a wheel.

bilateral symmetry

The body plan of animals in which the body can be divided into mirror image right and left halves by a plane passing through the midline of the body.

blastula

The hollow ball of cells that is the result of cleavage divisions in an early embryo.

gastula

The developmental stage resulting when the cells of the blastula migrate and divide once cleavage is complete

Diploblastic

An animal body plan in which adult structures arise from only two cell layers, the ectoderm and the endoderm.

Triploblastic

An animal body plan in which adult structures arise from three primary germ layers, endoderm, mesoderm, and ectoderm.

Ectoderm

The outermost of the three primary germ layers of an embryo, which develops into epidermis and nervous tissue

mesoderm

The middle layer of the three primary germ layers of an animal embryo, from which the muscular, skeletal, vascular, and connective tissues develop.

Endoderm

The innermost of the three primary germ layers of an embryo, which develops into the gastrointestinal tract and, in some animals, the respiratory organs

Acoelomate

A body plan of bilaterally symmetrical animals that lack a body cavity between the gut and the body wall.

Pseudocoelomate

A body plan of bilaterally symmetrical animals with a body cavity that lacks a complete lining derived from mesoderm.

Coelomate

A body plan of bilaterally symmetrical animals that have a coelom

coelom

A fluid-filled body cavity in bilaterally symmetrical animals that is completely lined with derivatives of mesoderm.

hydrostatic skeleton

A structure consisting of muscles and fluid that, by themselves, provide support for the animal or part of the animal; no rigid support, such as a bone, is involved.

Choanocytes

One of the inner layers of flagellated cells lining the body cavity of a sponge.

Spicules

Found in sponges, these consist of inorganic materials and support the animal; can be chalk, silica, or organic material

mesohyl

in a sponge, a gelatinous extracellular region between the two layers of cells

Amoebocytes

Cells that move using pseudopods and perform different functions in different animals

Mesoglea

in cnidarians, the jellylike material located between the ectoderm and the endoderm

Cnidocytes

A prey-capturing and defensive cell in the epidermis of cnidarians; stinging and look like small harpoons

Nematocysts

specialized organelles within cnidocytes that eject a stinging thread containing toxins to be injected into the predator or prey

polyp

The tentacled, usually sessile stage in the life cycle of a cnidarian

Medusa

The tentacled, usually bell-shaped, free-swimming sexual stage in the life cycle of a cnidarian

monoecious

having both the male and female reproductive organs in the same individual; hermaphrodite.

dioecious

Having male and female reproductive organs in separate plants or animals

Scolex

the anterior end of a tapeworm, bearing suckers and hooks for attachment.

Proglottids

one of the segmental structures that make up most of a tapeworm's body; each produce thousands of fertilized eggs

Cephalization

the concentration of nerve tissue and sensory organs at the anterior end of an organism

spiral cleavage

The cleavage pattern in many protostomes in which newly produced cells lie in the space between the two cells immediately below them.

radial cleavage

A cleavage pattern in deuterostomes in which newly formed cells lie directly above and below other cells of the embryo.

determinate cleavage

A type of cleavage in protosomes in which each cell's developmental path is determined as the cell is produced

indeterminate cleavage

A type of cleavage, observed in many deuterostomes, in which the developmental fates of the first few cells produced by mitosis are not determined as soon as cells are produced.

blastospore

the first opening made during gastrulation - the point of invagination

schizocoelom

In protostomes, the body cavity that develops as inner and outer layers of mesoderm separate.

enterocoelom

In deuterostomes, the body cavity pinched off by outpocketings of the archenteron.

Mantle

One or two folds of the body wall that lines the shell and secretes the substance that forms the shell in mollusks

radulla

in a mollusk, a structure of tiny teeth used for scraping food particles off a surface and drawing them into the mouth.

foot

The muscular structure in the bodies of many mollusks that is responsible for crawling or burrowing locomotion.

visceral mass

In mollusks, the region of the body containing the internal organs

mantle cavity

A water-filled chamber that houses the gills, anus, and excretory pores of a mollusc.

septum (pl. septa)

A thin partition or cross wall that separates body segments.

closed circulatory system

A circulatory system in which the fluid, blood, is confined in blood vessels and is distinct from the interstitial fluid.

open circulatory system

An arrangement of the circulatory system in some invertebrates in which, when the heart contracts, arteries leaving the heart release a bloodlike fluid, hemolymph, directly into body spaces called sinuses that surround organs

metanephridia

The excretory tubules of most annelids and mollusks.

parapodia

Fleshy lateral extensions of the body wall of aquatic annelids, used for locomotion and gas exchange.

Clitellum

Broad, thickened segments of annelids that holds the sperm and eggs

Trachea

In insects, an extensively branched, airconducting tube formed by invagination of the outer epidermis of the animal, and reinforced by rings of chitin. In vertebrates, the windpipe, which branches into the bronchi.

Malpighian tubules

The main organ of excretion and osmoregulation in insects, helping them to maintain water and electrolyte balance.

antennae

Sensory structures that are able to detect air movement, vibrations, and smells

book lungs

Pocketlike respiratory organs found in some arachnids consisting of several parallel membrane folds arranged like the pages of a book.

cephalothorax

region of a crustacean formed by the fusion of the head with the thorax

chelicerae

The first pair of fanglike appendages near the mouth of an arachnid, used for biting prey and often modified for grasping and piercing

pedipalps

each of the second pair of appendages attached to the cephalothorax of most arachnids. They are variously specialized as pincers in scorpions, sensory organs in spiders, and locomotory organs in horseshoe crabs.

Simple eyes

eyes that can sense only movement and light/dark and cannot form images

compound eyes

The eye of most insects and some crustaceans, composed of many faceted, light-sensitive units called ommatidia fitted closely together, each having its own refractive system and each forming a portion of an image.

exoskeleton

A hard external covering of an animal's body that blocks the passage of water and provides support and protection.

postembryonic development

the period of development after embryogenesis

Ametabolous

young look like adult, only sexually immature, continue to molt after maturity

Hemimetabolous

young resemble adult but lack wings (external wing pads), cease molting at maturity

Nymphs

The immature form of insects that look like small adults without fully developed wings

Holometabolous

young quite different from adult; complete metamorphosis; egg, larva, pupa, adult

larva

an immature form of an animal that looks very different from the adult

pupa

an insect in the inactive stage of development (when it is not feeding) intermediate between larva and adult