Animal Diversity (Exam 2)

Question 1

Acoelomate

Answer 1

Invertebrate lacking a coelom

Question 2

Archenteron

Answer 2

Rudimentary alimentary cavity of an embryo at the gastrula stage

Question 3

Bilateral Symmetry

Answer 3

Property of being divisible into symmetrical halves on either side of a unique plane

Question 4

Blastomere

Answer 4

Cell formed by cleavage of a fertilized ovum

Question 5

Blastospore

Answer 5

Asexual fungal spore produced by budding, within the phylum Glomeromycota and others (AKA blastoconidium)

Question 6

Blastula

Answer 6

Animal embryo at the early stage of development when it’s a hollow ball of cells

Question 7

Body Plan

Answer 7

Suite of characters shared by a group of phylogenetically related animals at some point during their development

Question 8

Cambrian Explosion

Answer 8

Biological Big Bang, time when almost all major animal phyla appeared on the fossil record

Question 9

Cleavage

Answer 9

After fertilization, development of a multicellular organism, series of mitotic divisions where enormous volume of egg cytoplasm is divided into numerous smaller nucleated cells

Question 10

Coelom

Answer 10

Fluid filled cavity of an animal that contains the internal organs (Heart, lungs, kidneys, etc.)

Question 11

Coelomate

Answer 11

Organisms that have a body cavity called coelom with a complete lining of peritoneum derived from mesoderm

Question 12

Cryogenian Period

Answer 12

Period of dynamic environmental change, about 720-635 mya

Question 13

Determinant Cleavage

Answer 13

Cell division in a fertilized or unfertilized egg resulting in daughter cells that aren’t able to produce a complete embryo by themselves

Question 14

Dueterostome

Answer 14

Develop an anus first within embryonic development

Question 15

Diploblastic

Answer 15

Having a body derived from only 2 embryonic cell layers (Ecto/endoderm, no mesoderm) such as sponges and coelenterates

Question 16

Ecdysozoa

Answer 16

Morphologically heterogenous group of animals that have a cuticle and grow by molting such as arthropods and nematodes

Question 17

Ectoderm

Answer 17

The outermost of the 3 germ layers or masses of cells which appears early in the development of an animal embryo

Question 18

Ediacaran Period

Answer 18

Interval of geological time ranging from 635-541 mya, intense change and was largely dominated by microscopic organisms

Question 19

Endoderm

Answer 19

The innermost of the 3 germ layers, or masses of cells (Between ecto/mesoderm) and appears early in the development of an animal embryo

Question 20

Enterocoely

Answer 20

Stage of embryological development of deuterostome in which the coelom forms

Question 21

Eucoelomate

Answer 21

Organism with a true coelom that surrounds the gut and is lined on both sides by mesoderm

Question 22

Eumetazoa

Answer 22

Major division of the animal kingdom comprising all multicellular forms except the sponges compare parazoa

Question 23

Gastrulation

Answer 23

Early developmental process in which an embryo transforms into a 1-dimensional layer of epithelial cells and reorganizes into a multilayered and multidimensional structure called the gastrula

Question 24

Hox Genes

Answer 24

Members of the homeotic transcription factor that plays a role in controlling the body plan (Along the cranio-caudal axis) and specify segment identity of tissue within an embryo

Question 25

Intermediate Cleavage

Answer 25

The early embryonic cells that retain the capacity to develop into a complete embryo such as echinoderms and vertebrates

Question 26

Lophophore

Answer 26

Characteristic feeding organ possessed by 3 major groups of animals, brachiopoda, bryzoa, phoronida, looks like a ring of tentacles

Question 27

Lophotrochozoa

Answer 27

A monophyletic group of animals that includes annelida, molluscs, bryozoans, brachiopods, platyhelminthes, and others that descended from a common ancestor

Question 28

Mass Extinction

Answer 28

When species vanish much faster than they're replaced, roughly 75% of the world species being lost in less than 2.8 mya

Question 29

Mesoderm

Answer 29

Germ layer that arises during gastrulation and is present between the ectoderm that produces the gut and lungs

Question 30

Organogenesis

Answer 30

The process of formation of organs from the 3 germ layers including cell-cell interaction, cell fate determination, cell proliferation and survival, cell and tissue shape/size, and arrangement of cells into tissues/functional organs

Question 31

Protostome

Answer 31

Develops a mouth first in embryonic development

Question 32

Pseudocoelomate

Answer 32

Organisms that have false body cavities, fluid filled bod that separates the organism from the body wall that ISN'T lined by mesoderm

Question 33

Radial Cleavage

Answer 33

Feature in early embryonic development of deuterostomes, results in daughter cells that are located exactly on top of one another

Question 34

Radial Symmetry

Answer 34

Symmetry around a central axis such as a starfish or tulip

Question 35

Schizocoely

Answer 35

Process by which some animal embryos develop, when secondary body cavities are formed by splitting a solid mass of mesodermal embryonic tissue

Question 36

Spiral Cleavage

Answer 36

Characteristic feature of protosomes, especially in a clade called spiralia, this results in daughter cels that aren't directly on top of one another, but are arranged spirally around the pole-to-pole axis

Question 37

Triploblastic

Answer 37

Having a body derived from 3 embryonic cell layers (Ecto/meso/endoderm) and are in all mulitcellular animals except sponges and coelenterates

Question 38

Trochophore Larva

Answer 38

Small, translucent, free-swimming larva, characteristic of marine annelids and most groups of mollusks, spherical/pear shaped and have a ring of cilia that enables them to swim