Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Hilary Term 1 > Arthropods I > Flashcards

Arthropods I Flashcards

1
Q

Describe the classification of the Ecdysozoa

A

superphylum

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

Which subphyla do the Ecdysozoa contain?

A
  • Panarthropoda
  • Nematoda
  • Nematomorpha
  • others
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the Panarthropoda

A
  • Tardigrada
  • Onychophora
  • Arthropoda
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the Arthropoda

A
  • emerged approximately 540Mya
  • 80% of all known animals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the arthropod common ancestor

A
  • homonomous
  • tagmosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Homonomy

A

a series of similar segments, with one appendage on each segment

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

Give the key characteristics of the extant arthropods

A
  • segmentation
  • jointed appendanges (the terminal of which is termed the telson), and an exoskeleton.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe arthropod segmentation - the basics

A
  • some have been specialised (sometimes in pairs)
  • some have been fused or lost in heteronomy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Heteronomy

A

segmentation remains apparent during embryonic development, but not in adult form

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

Describe arthropod segmentation - the basics

A
  • intersegmental articulation
  • tagmosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe intersegmental articulation

A

the segmentation of appendages

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

Describe tagmosis

A

grouping of segments with similar functions or structure

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

Describe jointed appendages

A
  • allows for bending between appendage articles through a flexible cuticle of the continuous exoskeleton at the joint
  • evolutionary innovation that overcomes the hard exoskeleton
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the mechanism of jointed appendages

A

to control hinged appendage movements, the antagonistic flexor and extensor muscles allow for lateral movement between sclerites, and protractor and retractor muscles allow for extension and retraction.

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

Describe tagmosis

A
  • evolved independently in the insect, crustacean and chelicerate groups
  • most arthropods exhibit some form of division tagmosis into the thorax and abdomen, where some develop a trunk
  • often specialised for other key life history functions, such as locomotion, reproduction, respiration and food manipulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the ubiquitous tagmosis within the arthropods

A

is the head, creating a specialised region for feeding, sensing and neural integration.

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

Give an example of tagmosis

A

Chelicerates fuse their head and thorax segments to form a tagmosed cephalothorax.

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

Describe the chitinous exoskeleton

A
  • integral to joint articulation
  • necessary for support provision and shape maintenance, as well as pathogen and injury protection
  • diverse properties, from stretchy tendons to hard carapace shells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe sclerotisation

A

tanning leads to cross-linking within the exoskeleton; enhanced strength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe the evolutionary constraints of the exoskeleton

A
  • lack of flexibility prevents dyanmic growth
  • ecdysis process
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe ecdysis

A
  • periodic moulting of the cuticle to allow for growth
  • multi-staged process
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe the process of ecdysis

A

1) pre-moult
2) moult
3) post-moult
4) inter-moult growth phase

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

Describe pre-moult

A

the old cuticle is detached and the new cuticle developed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Describe moult

A

the old cuticle is shed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Describe post-moult

A
  • new cuticle hardens
  • increased vulnerability associated pre-sclerotisation
  • 80-90% of arthropod mortality
26
Q

Describe inter-moult growth phase

A

can make up as a little as an approximate 10% of an arthropod’s life history

27
Q

Describe the evolutionary advantages of moult

A
  • contiunuouation of the exoskeleton for protection
  • facilitating growth to increase body size
  • explains why the majority of the arthropod’s life history is spent in-moult
28
Q

Describe the taxonomic classification of the Arthropoda (Regier et al., 2010)

A
  • four extant Subphyla: the Hexapoda, the Myriapoda, the Crustacea and the Chelicerata
  • one extinct subphylum, the Trilobites
29
Q

How many species does the Hexapoda contain?

A

> 800k species

30
Q

How many species does the Myriapoda contain?

A

16k species

31
Q

How many species does the Crustacea contain?

A

67k species

32
Q

How many species does the Chelicerata contain?

A

85k species

33
Q

Describe the Hexapoda

A

winged insects, as well as other wingless arthropod groups

34
Q

Describe the winged insects

A
  • 30 million species
  • 5 Major Orders: ants, Coleoptera, Lepidoptera, Diptera, and bees and wasps
  • metamorphosis
35
Q

Coleoptera

A

beetles

36
Q

Lepidoptera

A

butterflies and moths

37
Q

Diptera

A

flies

38
Q

Describe the basics of metamorphosis

A
  • either complete or incomplete
  • requires a moulting stage to reach sexual maturation
39
Q

Describe incomplete metamorphosis

A

demonstrating a nymphal stage

40
Q

Describe the Crustacean subphylum

A
  • huge morphological diversity
  • mostly marine
  • some species able to exist in freshwater and terrestrial environments
  • the key trophic link in marine ecosystems between primary producers and higher level consumers. - ten million tonnes of krill eaten and consumed each year
41
Q

Give the 6 Major Orders in the Crustacea

A
  • barnacles and woodlice
  • crabs
  • crayfish
  • krill
  • lobsters
  • shrimp
42
Q

Describe the Myriapod Subphylum

A
  • two Major Orders: the centipedes and and the millipedes
  • segmentation forms a head and trunk region with a single specialised antennae appendage and an open trachaea
43
Q

Describe the centipedes

A
  • approximtely 2.8k species
  • always have an odd number of legs
  • nocturnal active hunters
  • structurally specialised poison claw on the first trunk segment
  • modified anal legs on the last trunk segment
44
Q

Describe the millipedes

A
  • saprotrophs
  • secrete defensive toxic chemicals
  • diplosegments – two legs per segment
45
Q

Describe the open trachea structure of Myriapods

A

constrained to humid environments.

46
Q

Describe the anal legs of the centipedes

A

not locomotory, used for defence

47
Q

Describe the Chelicerata

A
  • chelicerae
  • independently invaded and radiated various dry land habitats
  • characteristic segmentation: two body segments (the cephalothorax and the abdomen)
  • compound eyes
48
Q

chelicerae

A

specialised pincer mouthpart appendages

49
Q

Describe the 5 Major Subphyla of the Chelicerata

A
  • Acari (mites and ticks)
  • Araneae (spiders)
  • Scorpiones (scorpions)
  • Pycnogonida (sea spiders)
  • Xiphosura (horse shoe crabs)
50
Q

Describe the Arachnids - the basics

A
  • pedipalps
  • box lungs
  • four pairs of legs
  • spinnerets
  • liquid carnivory
51
Q

Pedipalps

A

specialised appendages associated with the head

52
Q

spinnerets

A

modified appendages at the abdomen terminus

53
Q

Box lungs adaptations

A

extraordinarily high SA

54
Q

liquid carnivore adaptations

A

lack of mouthparts associated with solid food

55
Q

Describe the Arachnids - the specifics

A
  • approximately 40k species of spider
  • not particularly trophically diverse: almost exclusively predatory or parasitic
  • pedipalps for sperm transfer
  • innovated poison glands, some of which have been lost secondarily
56
Q

What is the most important innovation of the Arachnids

A
  • silk
  • composition varies across species
  • multi-optimisation innovation used in all aspects of the spider biology, from feeding, to reproduction, sensing, locomotion and dispersal
57
Q

How is silk used in feeding?

A

allows web building for vibration assessment

58
Q

How does silk aid locomotion?

A

silk draglining and abseiling

59
Q

How is silk used in dispersal?

A

ballooning spiderlings

60
Q

How have spiders colonised volcanic habitats?

A

passive flight

61
Q

Describe the Trilobites

A
  • extinct subphylum
  • highly abundant (approximately 17k species under 10 orders)
  • widely distributed
  • marine
  • survived for approximately 300My
  • fossils date back approximately 520Mya

Hilary Term 1 (61 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions