Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Invertebrates > Arthropods > Flashcards

Arthropods Flashcards

(60 cards)

Start Studying
1
Q

Ecdysozoans

A

the presents of Ecdysis (moulting)

(Both nematodes and arthropods show ecdysis and have a cuticle)

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

Cleavage?

A

NO SPIRAL CLEAVAGE

Example of a protostome without out spiral cleavage

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

Coelom?

A

Coelomates, coelom is very reduced.

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

Metamerically segmented

A

Body segment = somite

Appendages on segments

Groups of specialised segments are called tagmata (process is tagmosis)

Head → thorax → abdomen (segments separated into these three groups)

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

Hox genes

A

Tell cells which segment they are in. developmental genes that control the anterior/ posterior orientation

Different groups of arthropods have the same hox genes

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

Why is the cuticle so important?

A

Allows arthropods to be aquatic or terrestrial

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

Cuticle structure

A

Epicuticle

Pro-cuticle
→exo & endo cuticle

(The epidermis secretes the cuticle)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Pro-cuticle

A

Made up of chitin and protein bound together to form a glycoprotein

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

Exo-cuticle

A

is ‘Tanned’ = extra cross linkages that form which make it very toughened

Acts as support

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

Issues with the cuticle

A

Locomotion is difficult

Circulation

Gas exchange

Excretion

Growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Issues with the cuticle: Movement

A

Muscles are attached to the appendages and body

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

Issues with the cuticle: Circulation

A

coelom not needed for movement

has become reduced and combined with blood system to create HAEMOCOEL

Contains heart that pumped blood around system

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

Issues with the cuticle: Gas exchange

A

Specialised structured

gills and other structures

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

Issues with the cuticle: Excretion

A

Specialised enclosed structures

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

Issues with the cuticle: Growth

A

Ecdysis

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

What happens during ecdysis?

A
  • Epidermis secretes new cuticle
  • Releases proenzymes (unactivated enzymes)
  • Proenzymes become activated and start digesting proteins and chitin found in endocuticle
  • Animal uses fluid or air to expand size when cuticle is soft, once cuticle is hardened they can expel fluid/air and grow into cuticle
  • Growth starts to slow until moulting - growth happens in jumps
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Terrestrial arthropod size limitation

A

Coconut crab = largest terrestrial arthropod (50cm)

Giant spider crab = largest aquatic arthropod (4m)

aquatic environments can support larger sizes

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

Compound eye

A

Made up of ommatidia (up to 4000)

Sensitive to movement over large field of vision - magnification

Visual fields overlap

Poor resolution and image formation

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

Earliest group of arthropods ?

A

Trilobites

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

Trilobite body structure

A

divided into 3 sections (cephalon, thorax, pygidium)

Metameric segmentation

Biramous appendages - have two branches

Gnathobase

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

Biramous appendages

A

Two branches

filamentous (antennae)

Swimming or walking leg

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

Gnathobase

A

Grinding surface used to process food

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

Chelicerates Body structure

A

only 2 tagmata

Prosoma - top region - cephalothorax

Opisthosoma - bottom region - thorax

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

Characteristic features of chelicerates

A

Chelicerae - front appendages

Pedipalps - seconds pair of appendages

Next 4 pairs of walking legs

No antennae, no distinctive head

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Extant chelicerates (2 example marine species)
Horseshoe crab Sea spiders (pycnogonoids)
26
Horseshoe Crab Body features
Two tagmata (prosoma & Opisthosoma) Compound eyes Only chelicerate that has compound eyes Also has simple eyes
27
What is special about Horseshoe Crab blood?
* **Haemocyanin** (blue blood) contains copper * They are bled because the blood contains **limulus amoebocyte lysate** * Blood is able to detect endotoxins * Used to detect **endotoxins** present in medicine * (half a million are harvested every year)
28
Horseshoe Crab Respriation
Book gills
29
Horseshoe crab - reproduciton
Dioescious (seperate sexes) External fertilisation Mass spawning
30
Sea Spider Features
Prosoma reduced Digestive & reproductive organs found on legs
31
Sea spider Reproduction
Reproductive organs found on legs External fertilisation Male shows parental care Eggs held in place by ovigers (hook like structures on legs) Larvae are parasitic until developed into adult
32
What are some forms of terrestrial chelicerates?
Arachnids Spiders & Scorpions (ticks and mites are a subclass of arachnids)
33
Oldest group of Arachnids?
Scorpions over 400 million years old
34
Scorpion body structure
* Two body segments (prosoma & opisthosoma / cephalothorax & abdomen) * Chelicera first pair of appendages * Pedipalps - second pair of appendages (large pincers) * Median and lateral eyes * Pectines: Chemosensory - can detect chemicals
35
Scorpion sting apparatus
Telson - has photoreceptors
36
Scorpion respiration
Small entrances on underside lead to book lungs
37
Scorpion Reproduction
* Dioecious * Male deposits spermatophore on ground holds female and passes her over the spermatophore * Indirect internal fertilisation * Females give birth to live young * Broods offspring
38
How are a spider cheliceraes modified?
Modified into fang like structure Can inject neurotoxins into prey as use as defence
39
Spider Silk
* Spinnerets - spinning silk - produced by silk glands * Can produce different types of silk from different silk glands * Silk is produced for mating, dispersing, webs, wrapping prey, gift presenting etc * Strong substance * Made from Fibroin
40
Spider features
* Prosoma and opisthosoma * Small waist allows movement * 4 pairs of eyes
41
Spider: Digestive system
* Malpighian tubules: attached to gut, allows expulsion of waste products * Most are carnivorous: enzymes released from fangs digest prey which they then suck back up - **external digestion** * One species of veggie spider discovered (Bagheera kiplingi) collects beltian bodies from Acia trees (plant material)
42
Spider: Reproduction
Fertilisation: * **Internal indirect fertilisation** * Male puts sperm into **silk sac** then sucks up sac in their **pedipalp** which he then uses to insert sperm into female * Sexual dimorphism * Usually males smaller than females * Nephila sp extreme difference between sexes
43
Spider: Stabilimentum
Not clear what it does Lots of theories Prey attraction? Mating ritual? warning?
44
Co-operative spiders
live in large colonies and share food Feed on large items (co-operatively bring down larger prey)
45
Ticks and mites
Mites: free-living & parasitic form Ticks: Ectoparasites
46
Ticks and mites body structure
Two body sections are less distinguishable from one another prosoma is known as gnathosoma Hypostome: used by ticks to anchor onto prey
47
Ear mites
Vet worked on mites Awarded ignoble prize Infected himself with mites
48
Dust mites
Not parasitic but live in close contact with people
49
Ticks Lymes disease
Transmitted by bacteria spirochete
50
Crustaceans Habitat
Mostly aquatic Mostly marine Woodlouse is a terrestrial form
51
Crustaceans body form (Primitive)
Primitive form → head + thorax, appendages all the same 2 pairs of antennae
52
Crustacean sexes
Mostly dioecious Nautilus larval stage
53
Crustacean body form (Variation)
* More variation and radiation in evolved forms * Differentiation of appendages * Appendages are biramous - two branches. * Additional branch can be modified for food capture or respiration * 2 pair of antennae (characteristic for crustacea) * 1-3 thoracic appendages may be incorporated into head (maxillipeds)
54
Types of crustacea: Water Flea (daphnia)
* Two pairs of antennae * Reduced abdomen * Uses throaxes appendages for feeding * Parthenogenetic * When environmental conditions are harsh they favour sexual reproduction
55
Types of Crustacea: Barnacle
* Hermaphrodites * No abdomen * Dont have abdominal-A hox gene which controls abdomen formation. * Some species have the largest penis to body ratio found in the animal kingdom * Penis shape altered depending on environmental conditions
56
Types of crustacea: Parasitic Barnacles
* Parasitic barnacle (Sacculina) * Takes over host reproductive organs and controls it * Can change hosts behaviour * Disables reproduction so all the crabs energy goes into the parasite instead of reproducing.
57
2 Types of Myriapods
1. Centipedes 2. Millipedes *2 tagmata*
58
Centipedes
* Usually predacious * Maxilliped prehensor - poison claw * Modified appendages in anterior * 1 pair of antennae * Name means ‘hundreds of feet’ * Squashed flat - dorsally ventrally flattened
59
Millipedes
* Name = ‘thousands of legs’ * Each segment has two pairs of legs * Most are herbivorous * Rounded form * Able to emit chemicals for defence → excrete from repugnatorial glands
60
myriapod respiration
* Respire via tracheal system * Air is moved by muscles and diffusion * Excretion via malpighian tubules

Invertebrates (13 decks)

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