LECTURE 10

Question 1

advantage of not having cell wall

Answer 1

• mobility

Question 2

how many phyla do we have

Answer 2

36
diversified after cambrian explossion

Question 3

potential causes

what caused diversification during cambriange explosion (3)

Answer 3

1. evolution of novel adaptations by predators and prey (such as locomotion)
2. oxygen (sudden high rise, larger animals)
3. developmental genes, more variability (more capacity for adaptations)

Question 4

2 groups of animals

Answer 4

vertebrates and invertebrates

Question 5

what percentage of animals are invertebrates

Answer 5

more than 95%

Question 6

which phylum do humans come from

Answer 6

chrodate

Question 7

traits that differentiates animals

Answer 7

3. bilateral symmetry triploblastic
4. deuterosomes
5. protosomes

Animals ingest their food, lack cell walls and their sperms and eggs are produced directly through meiosis, not mitosis. Plants make spores, for example, that then divide and make gametes.

Question 8

Animals are ___ that ___ their food

Answer 8

Animals are heterotrophs that ingest their food

Question 9

Animals are ___ eukaryotes.

Answer 9

multicellular

Question 10

eukaryotic cells are supported and connected to one another by ___ and other structural proteins located ___ the cell membrane

Answer 10

collagen
outside

Question 11

2 key animal features?

Answer 11

nervous tissue and muscle tissue

Question 12

In most animals, ___ follows the formation of the ___ and leads to the formation of ___ tissue layers

Answer 12

In most animals, gastrulation follows the formation of the blastula and leads to the formation of embryonic tissue layers

Question 13

All animals except ___ have ___ genes

Answer 13

All animals except sponges have Hox genes

Question 14

what are hox genes

Answer 14

regulate the development of body form

Question 15

oldest known fossils of multicellular eukaryotes

Answer 15

small red algae

Question 16

Ediacaran period

Answer 16

rise of larger eukaryotes, mostly soft-bodied, set the stage for the cambrian explosion

Question 17

Prior to the Cambrian explosion, all large animals were:

Answer 17

soft-bodied

Question 18

there was little ___ before the cambrian explosion

Answer 18

predation

Question 19

what happenned to preys and predators AFTER the cambrian explosion?

Answer 19

• claws and other features for capturing prey; simultaneously,
• new defensive adaptations, such as
• sharp spines and
• heavy body armour, appeared in their prey

Question 20

sponges ___ from animals

Answer 20

diverged

Question 21

first animals to colonize land

Answer 21

arthropods

Question 22

what did the earliest tetrapods come from

Answer 22

earliest tetrapods found in the fossil record appear to have evolved from a group of lobe-finned fishes

Question 23

tetrapods include:

Answer 23

humans

Question 24

animals ___ their food and then use ___ to digest it within their bodies.

Answer 24

animals ingest their food and then use enzymes to digest it within their bodies.

Question 25

whats acts as a cell wall in eukaryotes?

Answer 25

**proteins external to the cell membrane** provide structural support to animal cells and connect them to one another

Question 26

___ is not found in plants or fungi

Answer 26

collagen

Question 27

muscle tissue is responsible for:

Answer 27

moving the body

Question 28

nervous tissue

Answer 28

conducts nerve impulses

Question 29

The ability to move and conduct nerve impulses underlies many of the adaptations that:

Answer 29

differentiate animals from fungi and plants

Question 30

in animals, the ___ dominates the diploid

Answer 30

diploid

Question 31

The haploid stage is composed of gametes (eggs and sperm) that are produced directly by :

Answer 31

meiotic division by the diploid stage

Question 32

The cells of the haploid stage do not undergo further cell division:

Answer 32

unlike plant and fungi

Question 33

The zygote then undergoes cleavage:

Answer 33

succession of mitotic cell divisions without cell growth between the divisions

Question 34

cleavage of eight-cell stage leads to:

Answer 34

the formation of a multicellular stage called a blastula which looks like a hollow ball

Question 35

what comes after the blastula stage?

Answer 35

gastrulation

Question 36

what is gastrulation

Answer 36

embryo folds inwards and then eneventually the layers of embryonic tissues that will develop into adult body parts are produced

Question 37

what is a larval stage

Answer 37

sexually immature form of an animal that is morphologically distinct from the adult, also eats different foods

Question 38

what is metamorphosis stage

Answer 38

developmental transformation that turns the animal into a juvenile that resembles an adult but is not yet sexually mature.

Question 39

what are homeobox/hox genes

Answer 39

controlling the expression of dozens or even hundreds of other genes that influence animal morphology.

Question 40

sponges do not have :

Answer 40

hox genes

Question 41

oldest known animals fossils:

Answer 41

ediacaran (pre cambrian)

Question 42

what is the cambrian explosion

Answer 42

Period of rapid evolution of new animal phyla, including the appearance of large, hard bodied animals.

Question 43

major increase in **mammal** diversity

Answer 43

cenozoic comes AFTER animal diveristy

Question 44

major increase in **animal** diversity

Answer 44

cambrian explosion (paleozoic)

Question 45

potential causes? more niches available : (2)

Answer 45

1. The evolution of novel adaptions by predators and prey 2. More plentiful oxygen allowing for larger body sizes

Question 46

potential causes? more capacity for adaptation:

Answer 46

Evolution of developmental genes that allow for more variability

Question 47

jellyfish and corals (cnidarians) are: (2)

Answer 47

diploblastic 2. eumetazoa phyla

Question 48

what does the coelom allows for? (2)

Answer 48

1. hydrostatic skeleton (maintains structure) 2. larger bodies with the same amount of cells

Question 49

3 ways to dinstinguish protosome and deuterosome development?

Answer 49

1. cleavage 2. coelom formation 3. fate of blastopore

Question 50

it is the ___ ___ of the human zygote that makes identical twins possible. which development type?

Answer 50

it is the indeterminate cleavage of the human zygote that makes identical twins possible. deuterostome

Question 51

# coelom formation As the archenteron forms in protostome development:

Answer 51

solid masses of meso- derm split and form the coelom

Question 52

# coelom formation As the archenteron forms in deuterostome development:

Answer 52

the mesoderm buds from the wall of the archenteron, and its cavity becomes the coelom.

Question 53

blastopore

Answer 53

The pouch formed by gastrulation, called the archenteron, opens to the outside via the blastopore.

Question 54

how is blastopore fate different in proto. and deutero.

Answer 54

Fate of blastopore Protostome: mouth develops first from the blastopore Deuterostome: anus develops first from the blastopore

Question 55

name 3 deuterostomes

Answer 55

hemichordates echinoderms chordates

Question 56

symmetry of echinoderms:

Answer 56

Echinoderms: - Bilateral larvae - - Radial adults

Question 57

2 groups of protostomes?

Answer 57

Lophotrochozoa Ecdysozoa

Question 58

which came first between Bilateria and Eumetozoa

Answer 58

Eumetozoa, tissues and radial symmetry (cnidaria)

Question 59

why are Ecdysozoans named for “**Ecdysis**”:

Answer 59

its the process of shedding and old exoskeleton

Question 60

name 2 Ecdysozoans

Answer 60

nematodes and arthropods

Question 61

___ make up 80% of animals

Answer 61

nematodes (roundworms)

Question 62

name 4 Lophotrochozoans

Answer 62

molluscs rotifers flatworms annelids

Question 63

what are the only 2 groups of truly terrestrials animals?

Answer 63

Vertebrate tetrapods: 360 mya Arthropods: 450 mya (from evidence in fossils from interaction with ferns)

Question 64

cephalization

Answer 64

an evolutionary trend towards a clustering of sensory neurons and interneurons at the ante- Brriaoinr (front) end of the body.

Question 65

blastula:

Answer 65

hollow ball of cells that marks the end of the cleavage stage during early embryonic development in animals

Question 66

coelmate

Answer 66

body cavity that forms from mesoderm such as ANNELIDS

Question 67

pseudocoelmate

Answer 67

body cavity form from MESODERM AND ENDODERM NEMATODE

Question 68

acoelmate

Answer 68

NO BODY CAVITY FLAT WORMS