Vocabulary Review Ch 32 – Intro to Animals

A multicellular, heterotrophic organism that lacks cell walls and that is usually characterized by movement and sexual reproduction; a member of Kingdom Animalia Animal

An animal that has a backbone; includes mammals, birds, reptiles, amphibians, and fish Vertebrate

An animal that does not have a backbone Invertebrate

The evolutionary adaptation of a cell, organ, organism, or population for a particular function or environment Specialization

The process of taking in food Ingestion

The cell that results from the fusion of gametes; a fertilized egg Zygote

The structural and functional specialization of cells during an organism’s development Differentiation

An animal that at some stage in its life cycle has a dorsal nerve, a notochord, and pharyngeal pouches; examples include mammals, birds, reptiles, amphibians, fish, and some marine lower forms Chordate

In the embryos of all chordates and in many adult chordates, a firm, flexible rod of tissue that is located in the dorsal part of the body Notochord

A neural tube dorsal to the notochord Dorsal nerve cord

One of the lateral sac that branch from the pharynx of chordate embryos and that may open to the outside as gill slits in adult fishes and invertebrate chordates Pharyngeal pouch

A body arrangement in which parts that lie on opposite sides of a central line are identical Symmetry

A body plan in which the parts of an animal’s body are organized in a circle around a central axis Radial symmetry

Lying on or near the back Dorsal

The lower or abdominal part of an organism Ventral

The front part of a body or structure Anterior

In animals with bilateral symmetry, refers to the end of the body that is opposite the head; rear Posterior

A condition in which two equal halves of a body mirror each other Bilateral symmetry

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

One of the layers of tissue that develop in the embryos of all animals except sponges Germ layer

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

A hard, external, supporting structure that develops from the ectoderm Exoskeleton

In aquatic animals, a respiratory structure that consists of many blood vessels surrounded by a membrane that allows for gas exchange Gill

A type of circulatory system in which the circulatory fluid is not contained entirely within vessels; a heart pumps fluid through vessels that empty into spaces called sinuses Open circulatory system

A circulatory system in which the heart circulates blood through a network of vessels that form a closed loop; the blood does not leave the blood vessels, and materials diffuse across the walls of the vessels Closed circulatory system

An organism that has both male and female reproductive organs Hermaphrodite

An independent and immature form of an organism that is morphologically different from the adult form Larva

An internal skeleton made of bone and cartilage Endoskeleton

One of the 33 bones in the spinal column (backbone) Vertebra

The outer, protective covering of a body, a body part, an ovule, or a sporangium Integument

The central organ of the respiratory system in which oxygen from the air is exchanged with carbon dioxide from the blood Lung

One of the organs that filter water and wastes from the blood, excrete products as urine, and regulate the concentration of certain substances in the blood Kidney

A compound that improves the quality of the soil to produce plants Fertilization

In biological development, a series of cell divisions that occur immediately after an egg is fertilized Cleavage

The stage of an embryo before gastrulation Blastula

The transformation of the blastula into the gastrula or the formation of the embryonic germ layers Gastrulation

The embryo in the stage of development after the blastula; contains the embryonic germ layers Gastrula

The primitive gastric cavity of an embryo Archenteron

An opening that develops in the blastula Blastopore

The outermost of the three germ layers of an embryo that develops into the epidermis and epidermal tissues, the nervous system, external sense organs, and the mucous membranes lining the mouth and anus Ectoderm

An animal that can generate body heat through metabolism and can maintain a constant body temperature despite temperature changes in the animal’s environment Endoderm

In an embryo, the middle layer of cells that gives rise to muscles, blood, and various systems Mesoderm

An animal that lacks a coelom, or body cavity Acoelomate

The type of body cavity, derived from the blastocoel and referred to as a “false body cavity,” that forms between the mesoderm and the endoderm in rotifers and roundworms Pseudocoelom

A body cavity that is completely lined by mesoderm and that contains the internal organs of an animal Coelom

An organism whose embryonic blastopore develops into the mouth, whose coelom arises by schizocoely, and whose embryo has determinate cleavage Protostome

An organism whose embryonic blastopore develops into an anus, whereas its mouth develops from a second opening at the opposite end of the archenteron; usually characterized by an embryo that undergoes indeterminate, radial cleavage Deuterostome

The method of coelom formation in protostomes in which the embryonic mesoderm splits into two layers Schizocoely

In deuterostomes, the method of coelom formation in which the embryonic mesoderm develops from pouches within the archenteron Enterocoely