taxonomy and diversity

acclimatisation

A process of gradual adaptation to a change in environment

Hetrotrophic

orginisms that obtain energy from the foods they consume

Neurons

Individual cells in the nervous system that receive, integrate, and transmit information.

muscle cells

Shorten to cause movement of the body. They move the skeleton, heart, and internal organs

morphological

characterizes a species by body shape and other structural features

phyla

In classification, the taxonomic category above class and below kingdom

Phylum

in classification, a group of closely related classes

taxonomic

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

branch

represents a population through time

Node

a point within the tree where a branch splits into two or more branches

outgroup

a taxon that diverged prior to the taxa that are the focus of the study; helps to root the tree

root

the most ancestral branch in the tree

Homology

Similarity in characteristics resulting from a shared ancestry.

monophyletic group

clade

lineage

A taxonomic grouping that includes an ancestral species and all of its descendants.

Synapomorphy

shared derived trait

Homoplasy

A similar (analogous) structure or molecular sequence that has evolved independently in two species.

polyphyletic group

an unnatural group that does not include the most recent common ancestor

paraphyletic group

A monophyletic group in which some descendants of the common ancestor have been removed.

Opisthokonta

the eukaryotic supergroup that contains the fungi, animals, and choanoflagellates

Choanoflagellates

a group of free-living unicellular and colonial flagellate eukaryotes considered to be the closest living relatives of the animals.

Morphology

study of form

body symmetry

radial and bilateral

Cephalization

formation of a head

Epithelium

layer of skin cells forming the outer and inner surfaces of the body

Tissue

A group of similar cells that perform the same function

germ layers

Three main layers that form the various tissues and organs of an animal body.

Diploblasts

animals whose embryos have two types of tissue (ectoderm and endoderm)

Triploblasts

animals whose embryos have three types of tissue (ectoderm, endoderm, mesoderm)

Ectoderm

outermost germ layer; produces sense organs, nerves, and outer layer of skin

Endoderm

innermost germ layer; develops into the linings of the digestive tract and much of the respiratory system

Mesoderm

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

digestive cavity

The cavity of the digestive organs, which opens to the exterior at the anus.

asymmetrical

no symmetry

radial symmetry

body plan in which body parts repeat around the center of the body

bilateral symmetry

Body plan in which only a single, imaginary line can divide the body into two equal halves.

nerve net

loosely organized network of nerve cells that together allow cnidarians to detect stimuli

central nervous system

consists of the brain and spinal cord

Ganglia

clusters of cell bodies in the PNS

Cerebal ganglion

brain

coelom

fluid-filled body cavity lined with mesoderm

tube within tube

Coelmate

The is a fluid-filled body cavity completely surrounded by mesoderm. (Fish, human)

Acoelomates

no body cavity

Pseudocoelomate

An animal whose body cavity is lined by tissue derived from mesoderm and endoderm.

hydrostatic skeleton

A fluid skeleton in many soft-bodied invertebrates, including annelids, that allows an organism to change shape but not volume.

Protosome

an organism who's blastopore forms the mouth (worms, arthopods, and mollusks)

Deuterostomes

Animals in which the blastopore becomes the anus during early embryonic development

Gastrulation

In animal development, a series of cell and tissue movements in which the blastula-stage embryo folds inward, producing a three-layered embryo, the gastrula.

Segmentation

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

Vertebrates (monophyletic)

backbone

Invertebrates

animals without a backbone

Cambrian explosion

A burst of evolutionary origins when most of the major body plans of animals appeared in a relatively brief time in geologic history; recorded in the fossil record about 545 to 525 million years ago.

sensory organs

Consists of the eyes, ears, nose, skin, and tongue.

life cycle

The generation-to-generation sequence of stages in the reproductive history of an organism.

Detritivore

organism that feeds on plant and animal remains and other dead matter

Herbivore

organism that obtains energy by eating only plants

Carnivore

organism that obtains energy by eating animals

Omnivore

organism that obtains energy by eating both plants and animals

endoparasite

parasite living on the inside of its host

Ectoparasites

parasites that live on the external surface of a host

suspension feeders

An aquatic animal, such as a clam or a baleen whale, that sifts small food particles from the water

Sessile

Describes an organism that remains attached to a surface for its entire life and does not move

deposit feeders

ingest organic material that has been deposited within a substrate or on its surface

fluid feeders

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

mass feeders

take chunks of food into their mouths

Homologous

term used to refer to chromosomes that each have a corresponding chromosome from the opposite-sex parent

fission or budding

mechanism of asexual yeast reproduction

parthenogenesis

Asexual reproduction in which females produce offspring from unfertilized eggs.

haploid gametes

sperm and egg

external fertilization

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

internal fertilization

fertilization of an egg by sperm that occurs inside the body of a female

viviparous

bearing live young

Oviparous

Eggs hatch outside the mother's body

Ovoviviparous

the embryo develops within the uterus and is nourished by the egg yolk

direct development

a kind of growth where organisms keep the same body features as they grow larger

indirect development

development of a juvenile animal into an adult while passing through intervening larval stages

Anatomy

The study of body structure

Physiology

The study of body function

Adaptation

A trait that helps an organism survive and reproduce

spermatrophe

sperm packet surrounded by a gelatinous mass

phenotypic

observable microscopic and macroscopic characteristics