Chapter 32

Question 1

What are animals

Answer 1

multicellular, heterotrophic, mobile organisms, with tissues that develop from embryonic layers

Question 2

Animal attributes

Answer 2

1. Multicellularity
2. Mobile
3. Consumers (heterotrophic)
4. Usually produce sexually and develop

Question 3

What is the difference between plant/fungus cells and animal cells?

Answer 3

Animal cells lack a cell wall for support.

Question 4

What supports animal cells and connects them to one another?

Answer 4

structural proteins

Question 5

What is the most abundant structural protein in animals that is not in plants/fungi

Answer 5

collagen

Question 6

Both animal cells and plant and fungal cells are organized into tissues, but what is unique to animals?

Answer 6

muscle and nervous tissues

Question 7

Autotrophs

Answer 7

generate own energy through photosynethsis or chemosythesis - “self-feeding”

Question 8

Heterotrophs

Answer 8

consume other living things or nonliving organic material (animals and fungi) - “other feeding”

Question 9

How do we distinguish animals and fungi if both are heterotrophic?

Answer 9

Animals ingest their food and digest it internally via enzymatic activity; fungi secrete digestive enzymes to breakdown food and then absorb it

Question 10

WHat usually dominates the life cycle of animals?

Answer 10

the diploid stage

Question 11

Zygote

Answer 11

diploid cell produced by the union of haploid gametes during fertilization; a fertilized egg

Question 12

Cleavage

Answer 12

succession of rapid cell divisions (mitosis) without growth during early embryonic development that converts the zygote into a ball of cells (blastula)

Question 13

Blastula

Answer 13

a hollow ball of cells that marks the end of the cleavage stage during ebryonic development

Question 14

Gastrulation

Answer 14

series of cell and tissue movements in which the blastula-stage embryo folds inward, producing a three-layered embryo (gastrula)

Question 15

Gastrula

Answer 15

embryonic stage in animal development encompassing the formation of three layers: ectoderm, mesoderm, and endoderm

Question 16

Larvae

Answer 16

free-living, sexually immature form in some animal life cycles that may different from the adult animal in morpholog nutrition, and habitat

Question 17

Metamorphosis

Answer 17

developmental transformation that turns an animal larva into either an adult or an adult-like stage that is not yet sexually mature

Question 18

Juvenile

Answer 18

post-larval stage that is not yet reproductively mature

Question 19

Adult

Answer 19

reproductively mature stage

Question 20

Stages of reproduction and development

Answer 20

1. Sperm fertilizes egg to form diploid zygote
2. Zygote undergoes cleavage to form blastula
3. Blastula undergoes gastrulation forming gastrula

Question 21

Homeobox genes (Hox genes)

Answer 21

Regulatory genes found in most animals and only animals (not sponges). Regulate development of body form (anterior-posterior axis)

Question 22

A mutation of the HoxD13 gene

Answer 22

Synpolydactyly

Question 23

When did the common ancestor of all living animals likely live?

Answer 23

about 770 mya

Question 24

A group of protists that are likely the closest living relatives to animals

Answer 24

choanoflagellates

Question 25

HOw many living animal species are there to date?

Answer 25

1.3 million - for more are estimated to exist

Question 26

What evidence shows that the common ancestor of all animals may have resembled modern choanoflagellates?

Answer 26

1. the origin of multicellularity requires the evoltion of new ways for cells to attach and communicate to each other 2. Choanoflagellates and animals have sequence similarities in genes involved in adherence and attachment

Question 27

What specific gene coding for a group of proteins do both choanoflagellates and animals have?

Answer 27

cadherins

Question 28

What do a nimals have that choanoflagellates don't?

Answer 28

the CCD domain (novel cadherin protein domain)

Question 29

Neoproterozoic Era

Answer 29

(1bya - 542 mya) - ediacaran biota - evidence of predation

Question 30

Ediacaran biota

Answer 30

soft bodied multicellular eukaryotes

Question 31

soft bodied multicellular eukaryotes

Answer 31

Ediacaran biota

Question 32

First generally accepted macroscopic fossils of animals

Answer 32

Ediacaran biota

Question 33

Palezoic Era

Answer 33

(542-251 mya) - cambrian explosion - animal diversity continues to increase

Question 34

Cambrian explosion

Answer 34

marks the earliest fossil appearance of many major groups of living animals

Question 35

Most fossils from the Cambrian explosion are...

Answer 35

bilaterians 1. bilaterally smmetric 2. complete digestive tract 3. one-way digestive system

Question 36

What caused the Cambrian Explosion?

Answer 36

1. new predatory-prey relationships 2. rise in atmospheric oxygen (enabled animals with higher metabolic rates and larger body sizes to thrive) 3. evoltuion of Hox gene

Question 37

New predatory-prey relationships that caused the Cambrian Explosion

Answer 37

1. Predators evolved novel traits for catching prey 2. Prey evolved new defenses (protective shells) - (decline in soft bodied Ediacaran biota)

Question 38

How does animal diversit continue to increase through Paleozoic

Answer 38

1. Arthropods are first animals to transition to land | 2. vertebrates colonize land

Question 39

Mesozoic Era

Answer 39

(251-65.5 mya) 1. coral reefs emerged 2. ancestors of plesiosaurs were reptiles that returned to the water 3. dinosaurs 4. first mammals 5. angiosperm radiation

Question 40

Cenozoic Era

Answer 40

(65. 5 mya - present) - rise of mammals - first primates appear in Africa

Question 41

The beginning of cenozoic era followed...

Answer 41

mass extinctions of terrestrial and marine animals

Question 42

What is considered when categorizing animals?

Answer 42

1. Symmetry (or lack thereof) 2. Tissues 3. Body Cavity 4. Embronic Development

Question 43

Symmetry

Answer 43

1. asymmetrical 2. radial symmetry 3. bilateral symmetry

Question 44

Radial animals

Answer 44

often sessile or planktonic (drifting or weakly swimming)

Question 45

What is bilateral symmetry accompanied by?

Answer 45

cephalization

Question 46

cephalization

Answer 46

concentration of sense organs and nervous control at the anterior end of the body (head and brain/ganglia)