Animal Origin

Question 1

Cambrian explosion

Answer 1

rapid diversification of animal body types & lineages

Question 2

animal

Answer 2

member of major lineage of eukaryotes (Animalia)

• typically complex, large, multicellular body
• eat other orgs
• mobile

Question 3

body plan

Answer 3

basic architecture of animal’s body

- including: number & arrangement of limbs, body segments & major tissue layers

Question 4

sessile

Answer 4

permanently attached to a substrate

- not capable of moving to another location

Question 5

choanocytes

Answer 5

specialized, flagellated feeding cell found in choanoflagellates (closest related living animal relative) & sponges
- most ancient animal phylum

Question 6

colonies

Answer 6

assemblage of individuals (semi-independent cells or breeding population of multicellular orgs)

Question 7

tissue

Answer 7

group of cells that fcn as a unit

(ie) muscle tissue - animal or xylem tissue - plant

Question 8

lophotrochozoans

Answer 8

major lineage of protostomes

• grow by extending size of exoskeletons, not molting
• many phyla = specialized feeding structure (lophophore) or ciliated larvae (trochophore)

(ie) rotifers, flatworms, segmented worms & mollusks

Question 9

ecdysozoan

Answer 9

major lineage of protostomes
- grow by molting & expanding bodies

(ie) arthopods, nematodes, etc

Question 10

segmentation

Answer 10

body or part of it is divided into series of similar structures
- exemplified by body segments of insects, worms, & somites of vertebrates

Question 11

vertebrate

Answer 11

1 of 3 major chordate lineages (Vertebrata)
- animals w/ dorsal column of cartilaginous or bony structures & skull enclosing brain

(ie) fish, amphibians, mammals & reptiles

Question 12

invertebrate

Answer 12

paraphyletic group composed of animals w/out a backbone

- includes 95% of all animal species

Question 13

benthic

Answer 13

living @ bottom of aquatic environment

Question 14

polyp

Answer 14

sessile stage in life cycle of some cnidarians (jellyfish)

Question 15

medusa

Answer 15

free-floating stage in life cycle of cnidarians

Question 16

cnidocyte

Answer 16

specialized stinging cell found in cnidarians

- used in capturing prey

Question 17

Cambrian Explosion diversitfication

Answer 17

(1) increased oxygen levels
(2) predation evolution: sessile to predators w/ shells & skeleton; increased movement
(3) new riches -> new niches (ecological diversification)
(4) new genes, new bodies

Question 18

germ layers

Answer 18

embryonic tissue layers

- types: diploblast & triploblast

Question 19

diploblast

Answer 19

animals whose embryos have 2 types of tissue

• “two buds”
• ectoderm + endoderm

Question 20

triploblast

Answer 20

animals whose embryos have 3 types of tissue

• “three buds”
• ectoderm + mesoderm + endoderm

Question 21

ectoderm

Answer 21

skin & nervous system

Question 22

mesoderm

Answer 22

circulatory system, muscle & internal structures (bone/organs)

Question 23

endoderm

Answer 23

digestive tract lining

Question 24

radial symmetry

Answer 24

“spoke symmetry”

• at least 2 planes of symmetry
• older than bilateral
• evolved from phylum Echinodermata
• attracts more prey

Question 25

bilateral symmetry

Answer 25

"2 sides symmetry" - 1 plane of symmetry (lengthwise, down middle) - occurs in triploblastic lineages

Question 26

cephalization

Answer 26

evolution of a head or anterior region

Question 27

nerve net

Answer 27

nerve cells organized into diffuse arrangement | - all over body, cover everything

Question 28

central nervous system

Answer 28

some neurons clustered into 1 or more tracts/cords that project throughout body - like a tree w/ roots

Question 29

body cavaties

Answer 29

enclosed fluid-filled chamber act as hydrostatic skeleton (1) coelem (2) pseudocoelem (3) acoelmate

Question 30

coelem

Answer 30

fluid-filling cavity btwn inner & outer tubes | - coelemates: bilaterians w/ coelem

Question 31

pseudocoelem

Answer 31

bilaterians that retained coelem but lost mesodermal lining in parts of coelem - "false-cavity form" (ie) round worms

Question 32

acoelomates

Answer 32

bilaterians that lost coelem - "no cavity form" (ie) flatworms

Question 33

protostome

Answer 33

mouth before anus development - "first mouth" - blocks of mesoderm hollow out to form coelem

Question 34

deuterostome

Answer 34

anus before mouth development - "second mouth" - pockets of mesoderm pinch off to form coelem

Question 35

gastrulation

Answer 35

formation of gut & embryonic germ layers

Question 36

food sources

Answer 36

(1) detritivore (2) herbivore (3) carnivore (4) omnivore

Question 37

detritivore

Answer 37

feed on dead organic matter

Question 38

herbivore

Answer 38

feed on plants & algae

Question 39

carnivore

Answer 39

feed on animals

Question 40

omnivore

Answer 40

feed on animals & plants

Question 41

types of consumers

Answer 41

(1) predators (2) parasites (3) endoparasites (4) ectoparasites

Question 42

feeding tactics

Answer 42

(1) suspension feeding (2) deposit feeding (3) fluid feeding (4) mass feeding

Question 43

suspension feeder

Answer 43

trap suspended particles - usually eat detritus, plankton, small orgs in currents - (ie) sponges, clams, mussels, baleen whales, barnacles - aka filter feeders

Question 44

deposit feeder

Answer 44

digest organic matter in sediments - food: sand or mud-dwelling bacteria, archaea, protists & fungi - similar in appearance (ie) earthworms

Question 45

fluid feeder

Answer 45

food source: nectar - found in wide lineages array - often have mouth parts that allow them to pierce seeds, stems, skin, etc. (ie) butterflies, moths, vampire bats

Question 46

mass feeder

Answer 46

ingest chunks of food - mouth structure correlates w/ food pieces (ie) lions - razor teeth tare bite & snails - radula scrap

Question 47

types of reproduction

Answer 47

(1) asexual - mitosis | 2) sexual - meiosis + fusion of gamates (increase genetic diversity

Question 48

where fertilization occurs

Answer 48

(1) internal | (2) external

Question 49

internal fertilization

Answer 49

male insert sperm-transfer organ into female body

Question 50

external fertilization

Answer 50

male produce sperm in packets, female picks up & inserts into own bodies - (seahorse) female insert eggs for male body - common in aquatic species

Question 51

types of embryo development

Answer 51

(1) vivaporous (2) oviparous (3) ovoviviparous

Question 52

vivaporous

Answer 52

nourish embryos internally; give birth to live young - most mammals, sea stars, velvet worms, fish, amphibians - "live bearing"

Question 53

oviparous

Answer 53

deposit fertilized eggs; embryos nourished by yolk - most insects, birds & animals "egg bearing"

Question 54

ovovivaparous

Answer 54

retain eggs internally, give birth to live young, embryos nourished by yolk inside egg - guppies, garter snakes, reptiles & some snail "egg-live bearing"

Question 55

metamorphosis

Answer 55

drastic change from one developmental stage to another - common in marine animals, insects & many amphibians - direct & indirect "change form"

Question 56

direct metamorphosis

Answer 56

young adult version looks like adult version (ie) animals

Question 57

indirect metamorphosis

Answer 57

larvae, juvenile & adult form - all live in diff. environment - each stage eat diff. food

Question 58

larvae

Answer 58

indirect metamorphosis stage 1 - embryogenesis =diff. from adults - live in diff. habitats - eat diff. food

Question 59

juveniles

Answer 59

indirect metamorphosis stage 2 - look like adults - live in same habitat - eat same food

Question 60

adults

Answer 60

indirect metamorphosis stage 3 - maturation - stage of reproduction