Bio 152 Exam 2 Terminology

Allantois

involved in early fluid exchange between the embryo and the yolk sac

Extremophile

organism that grows under extreme or harsh conditions

Ubiquitous

present or existing everywhere

Enrichment culture

encourages growth of desired microbe

Metagenomics

the study of genetic material recovered directly from environmental samples

Molecular phylogeny

The study of evolutionary relationships using comparative genomics

Binary fission

A form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size

Protist

Kingdom composed of eukaryotes that are not classified as plants, animals, or fungi

Absorptive feeding

occurs when nutrients are taken up across the plasma membrane directly from the environment

Ectoderm

the outer germ layer that develops into skin and nervous tissue

Cephalization

concentration of sense organs and nerve cells at the front of an animal's body

Endoparasite

A parasite that lives within a host.

Mass feeder

ingest chunks of food

Exoskeleton

hard protective structure developed outside the body

Pharyngeal gill slits

all chordates share this, appear in the pharynx at some stage in their development, evolved to aid in respiration and filter feeding

Notochord

A flexible rod that supports a chordate's back

Dorsal hollow nerve cord

nerve cord found in all chordates that forms the spinal cord and brain

Marsupials

pouched mammals

Placenta

A structure that allows an embryo to be nourished with the mother's blood supply

Transduction

conversion of one form of energy into another

Conjugation

In bacteria, the direct transfer of DNA between two cells that are temporarily joined.

Transformation

A change in genotype and phenotype due to the assimilation of external DNA by a cell.

Gram-positive

stains purple

Gram-negative

stains pink

Autotroph

An organism that makes its own food

Heterotroph

organism that obtains energy from the foods it consumes; also called a consumer

Phototroph

an organism that gets its energy from sunlight

Chemolithotroph

an organism that obtains its energy from the oxidation of inorganic compounds

Chemoorganotroph

an organism that obtains its energy from the oxidation of organic compounds

Endosymbiosis

one of the organism lives inside the other

Endosymbiotic Theory

a theory that states that certain kinds of prokaryotes began living inside of larger cells and evolved into the organelles of modern-day eukaryotes

Symbiosis

A close relationship between two species that benefits at least one of the species.

Unicellular

Made of a single cell

Multicellular

made of many cells

Single nucleate

has one nucleus

multinucleate

many nuclei

Amoeboid

A type of protozoa that moves with pseudopodia

Flagella

whiplike tails found in one-celled organisms to aid in movement

Cilia

The hairlike projections on the outside of cells that move in a wavelike manner

Phagocytosis

process in which extensions of cytoplasm surround and engulf large particles and take them into the cell

Ciliary feeding

movement of cilia causes a current of water to be drawn towards and through the animal

Asexual reproduction

Process by which a single parent reproduces by itself

Sexual reproduction

A reproductive process that involves two parents that combine their genetic material to produce a new organism

Alternation of generations

the alternation between the haploid gametophyte and the diploid sporophyte in a plant's life cycle

Spores

typically one-celled reproductive unit capable of giving rise to a new individual without sexual fusion

Gametes

reproductive cells

Gametophyte

Haploid, or gamete-producing, phase of an organism

Sporophyte

Diploid, or spore-producing, phase of an organism

Diploid

2 sets of chromosomes

Haploid

having a single set of unpaired chromosomes

Opisthokonta

fungi, choanoflagellates, animals

Multicellularity

Allows for differentiation of cells into tissues

Diploblasts

animals who have two types of tissue (ectoderm and endoderm)

Triploblast

animal that has three tissue layers (ectoderm, mesoderm, endoderm)

Endoderm

the inner germ layer that develops into the lining of the digestive and respiratory systems

Mesoderm

middle germ layer; develops into muscles, and much of the circulatory, reproductive, and excretory systems

Bilateral Symmetry

divisible into symmetrical halves

radial symmetry

body parts repeat around the center of the body

Nerve net

a netlike control system that sends signals to and from all parts of the body

Central Nervous System

brain and spinal cord

Coelem

fluid filled body cavity

Pseudocoelom

body cavity that is only partially lined with mesoderm

Acoelom

no body cavity

Segmentation

the division of the body of an organism into a series of similar parts

Predators

animals that hunt other animals for food

Herbivores

plant eaters

Parasite

An organism that feeds on a living host

Ectoparasite

lives on the surface of the host

Suspension feeder

An aquatic animal that sifts small food particles from the water.

Deposit feeder

an animal that feeds on organic matter that settles on the bottom

Fluid feeder

an animal that lives by sucking nutrient-rich fluids from another living organism (mosquito

Internal fertilization

Process in which eggs are fertilized inside the female's body

External fertilization

process in which eggs are fertilized outside the female's body

Choanocyte

Collar cells that line the body cavity and have flagella that circulate water in sponges

Cnidocyte

a stinging cell of a cnidarian

Colloblast

secrete a sticky substance that binds to their prey

Medusa

A free-swimming cnidarian with a bell-shaped body and tentacles

Polyp

growth extending from the surface of mucous membrane

Lophotrochzoa

Flatworms, Molluscus, Cephalopods

Lophophore

a crown of ciliated tentacles that function in feeding

Trochophore

free-swimming larval stage

Spiral cleavage

Cells divide in a spiral arrangement

Platyhelminthes

flatworms

Annelida

segmented worms

Oligachaeta

earthworms, some marine and fresh water forms. few bristles

Polychaeta

bristle worms

Hirudinea

leeches

Mollusca

(snails, clams, squids, octopuses) have a soft body that in many species is protected by a hard shell

Muscular foot

used for movement

Visceral mass

area beneath the mantle of a mollusk that contains the internal organs

Mantle

covers the visceral mass and usually protrudes in the form of flaps

Hemocoel

blood cavity

Gastropoda

snails and slugs

Bivalvia

The class of the phylum Mollusca that includes clams, oysters, and mussels.

Radula

An organ covered with teeth that mollusks use to scrape food into their mouths

Polyplacophora

class of chitons

Cephalopoda

squid, octopus

Molting

the process of shedding an outgrown exoskeleton

Cuticle

any of a variety of tough but flexible, non-mineral outer coverings of an organism

Nematoda

Phylum of roundworms