Arthropods - Chelicerata

Question 1

What are the characteristics of Chelicerata?

Answer 1

Cephalothorx+Abdomen
4 pairs of marching legs
No antenna
Simple and compound eyes
Chelicerae/pedipalps

Question 2

Cephalothorax(Prosoma)

Answer 2

This contains a fused head and thorax with an exoskeleton.

Question 3

What structures are found on the head?

Answer 3

Chelicerae, Pedipalps and the Eyes

Question 4

Chelicerae(Fangs)

Answer 4

These are pincerlike appendages instead of mandibles.

Question 5

Pedipalps(Sensory)

Answer 5

These are a pair of finger-like projections located laterally on either side of the hypostome

Question 6

What are chelicerae and pedipalps used for?

Answer 6

Venom injection/feeding and grasping/manipulation respectively

Question 7

What is the struture of the walking legs?

Answer 7

Terminated with tarsal claws(vDW forces) and antagonistic musculature.

Question 8

How do muscles attach in the legs?

Answer 8

Inside of the exoskeleton with force generation by contraction and pulling.

Question 9

How do spiders attach to walls?

Answer 9

VDW by setae hairs with ndividual branches called spatulae providing large surface area

Question 10

Abdomen(Opisthosoma)

Answer 10

This is comprisedd of a fused head and thorax and is covered dorsally by a carapace and ventrally by a sternal plate

Question 11

What is the general structure of teh abdomen?

Answer 11

10-12 segments, containing the circulatory, digestive, reproductive and excretory systems

Question 12

What is the structure of the digestive system?

Answer 12

Fore, mid and hindgut

Question 13

Malpighian Tubules

Answer 13

These transports urine and urinary metabolits for excretion

Question 14

What is the structure of the malpighian tubules?

Answer 14

They emerge from the gut providiing ecretion of nitrogenous waste products generated from protein-breakdown

Question 15

What is the sturcture of the book lungs?

Answer 15

Lamellae layers in a pulmonary cavity

Question 16

What is the mechanism of the book lungs?

Answer 16

Inhaltation with gas exchange through spiracles with diffusion/distribution into the hemolymp

Question 17

Spiracles

Answer 17

These are openings of the tracheal system of the integument of the insect

Question 18

What is O2 transport faciltitaed by?

Answer 18

Hemocyanins

Question 19

Hemocyanins

Answer 19

These are an oxygen transport protein found in inverebrate aniamsl

Question 20

What are the reproductive structures of males?

Answer 20

They contain sperm-producing testes and seminal fluid-producing accessory glands.

Question 21

Spermatophore

Answer 21

These are reproductive structures packaing sperm cells to aid in their transmission to females during mating

Question 22

What are the classes of chelicerata?

Answer 22

Arachnida

Question 23

Arachnida

Answer 23

These are defined by their chelicerae, pedipalps, cephalothorax and abdomen.

Question 24

What are the orders of Arachnid?

Answer 24

Araneae
Opilliones
Acari
Scorpiones

Question 25

Araneae

Answer 25

Contain a body with a seperated waist

Question 26

Opilliones(Harvestmen)

Answer 26

They have no body waist but still distinctly segmented with an ocular tubercule and legs twice the body length.

Question 27

Ocular Tubercule

Answer 27

These are large spherical structures in clustered pairs

Question 28

Acari(Mites)

Answer 28

These have no waist and are not visbily segmented, with legs shorter than the body.

Question 29

What are compound eyes composed of?

Answer 29

Ommatidia

Question 30

Ommatidia

Answer 30

These are made of pigmented photoreceptor cells in clusters

Question 31

Photoreceptor Cell

Answer 31

These are differentiated postmitotic retinal neurons

Question 32

What do webs derive from?

Answer 32

Produciton of silk proteins called fibroins.