Lecture 15 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

5 characteristics of animals (not unique)

A
  1. multicellular (except gametes)
  2. lack cell walls
  3. chemoheterotrophic
  4. mostly sexual and do not show alternation of generations (motile haploid sperm
    fertilizes larger non-motile haploid egg to make
    diploid zygote)
  5. animate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

metazoans

A

name sometimes used for animals, to distinguish from single-celled protozoans (non-photosynthetic single-celled eukaryotes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

chemoheterotrophy in animals

A

cannot make own carbon-based food source, get it from other organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

animate

A

capable of moving entire multicellular body in at least one stage in life cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

3 characteristics of animals (unique)

A
  1. extracellular collagen
  2. 3 unique types of intercellular junctions
  3. Hox genes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

extracellular collagen

A

glycoprotein (protein + bonded carbohydrate) strands in a matrix surrounding cells, ≥ 90% of protein in animal body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

3 types of intercellular junctions (connecting structures between cells)

A
  1. tight junctions
  2. desmosomes
  3. gap junctions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

homeobox genes

A

a set of regulatory genes that produce proteins that can turn other genes on and off

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Hox genes

A

homeobox genes that control anterior to posterior developmental sequence of embryo, absent in sponges and ctenophores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

embryonic development in animals

A
  1. haploid gametes of different sizes (anisogamy)
  2. diploid zygote undergoes cleavage
  3. blastula forms
  4. gastrulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

anisogamy

A

small motile sperm, large nonmotile eggs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

cleavage

A

many mitotic cell divisions without growth of cells between divisions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

blastula

A

hollow ball of cells formed after cleavage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

gastrulation

A

blastula invaginates (folds into itself) at one end

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

gastrula

A

two clear layers of cells - endoderm and ectoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

2 types of development in animals

A
  1. direct development

2. indirect development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

direct development

A

embryo gradually develops towards adult form without sudden changes in morphology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

indirect development

A

intermediate stages (larvae) whose morphology and behaviour differs greatly from sexually mature adult stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

traditional view 3 dichotomies

A
  1. presence of true tissues
  2. symmetry
  3. embryonic development
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

tissue

A

integrated group of cells with common structure and function, isolated from other tissues by membranous layers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

animals without true tissues

A

sponges and placozoans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

animals with true tissues

A

eumetazoa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

radial symmetry

A

top and bottom, but no left or right, can be divided into many planes of symmetry “radiata”

24
Q

bilateral symmetry

A

have a top, bottom, left and right, only one plane of symmetry (Bilateria)

25
Q

diploblastic

A

endoderm and ectoderm - Radiata

26
Q

triploblastic

A

endoderm, ectoderm, and mesoderm - Bilateria

27
Q

endoderm

A

becomes gut

28
Q

ectoderm

A

becomes skin and nerves

29
Q

mesoderm

A

becomes muscles

30
Q

acoelomate

A

solidly packed bilaterian with no body cavity

31
Q

eucoelomate

A

bilaterians with body cavity that is completely lined with mesodermally derived tissues

32
Q

pseudocoelomate

A

bilaterians with coelom that lack complete mesodermal lining

33
Q

3 functions of coelom

A
  1. cushions internal organs from blows to body
  2. allows internal organs to shift without deforming outside of body
  3. fluid-filled cavity can be used as hydrostatic skeleton
34
Q

2 types of embryonic development

A
  1. protostome

2. deuterostome

35
Q

4 characteristics of protostomia

A
  1. first invagination of the gastrula (blastopore) becomes the mouth
  2. spiral cleavage
  3. determinate cleavage
  4. schizocoely
36
Q

4 characteristics of deuterostomia

A
  1. second invagination becomes the mouth
  2. radial cleavage
  3. indeterminate cleavage
  4. enterocoely
37
Q

spiral cleavage

A

new row of cells is twisted slightly off centre (protostomes)

38
Q

radial cleavage

A

each cell division stacks the new cells directly above the previous ones (deuterostomes)

39
Q

determinate cleavage

A

in early embryos, each new cell destined to form some part of the later embryo (removal of some cells results in embryo missing organs)

40
Q

indeterminate cleavage

A

early embryonic cells not differentiated (could split young embryo and get two complete later embryos)

41
Q

schizocoely

A

solid blocks of mesoderm split internally to create fluid-filled hollows

42
Q

enterocoely

A

mesoderm is at one end of embryonic gut, outpocketings of mesoderm pinch off to make fluid-filled hollows

43
Q

new view - protostome dichotomy

A
  1. lophotrochozoa

2. ectdysozoa

44
Q

arthropoda placement

A

old view - with Annelida (segmented worms)

new view - with Nematoda (unsegmented worms)

45
Q

Ectysozoa

A

all moult their entire cuticle at once in order to grow, some

46
Q

lophophore

A

tentacle-covered feeding structure, characteristics of proto- and deuterostomes

47
Q

trochophore

A

larval stage similar to ectysozoans

48
Q

Lophotrochozoa

A

lophophores and trochophores placed together by molecular data

49
Q

choanoflagellates

A

(140, marine) common ancestor of animalia, heterotrophic protists with single flagellum surrounded by collar of microvilli, solitary or colonial, cell morphology similar to sponge

50
Q

microvilli

A

fingerlike projections of cell membrane

51
Q

oldest known fossil of multicellular eukaryotes

A

1.2 BYA, trace fossils of worm burrow 1.1 BYA, fossil embryos 570 MYA, whole body 565 MYA (Precambrian)

52
Q

Cambrian explosion

A

535-525 MYA, most major animal phyla appeared ‘suddenly’ in a short period, including complex life with skeletons, origin of Hox genes possibly allowed diversification of body plans

53
Q

Ediacaran biota

A

Precambrian animal fossils, 635-542 MYA “pillow animals” South Australia

54
Q

Mistaken point biota

A

Precambrian animal fossils, 565 MYA Ediacaran biota, Newfoundland

55
Q

Drook formation biota

A

Precambrian animal fossils, 575 MYA Ediacaran biota, Newfoundland

56
Q

small shelly fauna

A

fossils at beginning of Cambrian (542 MYA)

57
Q

Burgess shale

A

(510-505 MYA) first discovered Cambrian explosion site, U.S. paleontologist C.D. Walcott visiting B.C. fossil bed, fossils of soft- and hard-bodied taxa, good preservation likely due to quick death and burial by a mudslide, intermediate between ‘weird wonders’ and modern taxa