Arthropods

Question 1

3 common characteristics

Answer 1

A tough exoskeleton, jointed appendages, a segmented body.

Question 2

Characteristics of the phylum

Answer 2

Makes up over 90% of the animal kingdom, found in air, on land, in water, shares 3 common characteristics.

Question 3

Tough exoskeleton

Answer 3

External support structure, made of chitin (a carbohydrate). Functions: body support, protection of soft body parts, attachment point for muscles, prevents water loss.

Question 4

Jointed appendages

Answer 4

Arthro = joint, pod = foot. Includes structures such as legs, antennae, claws, wings, and flippers, that extend from the body wall.

Question 5

A segmented body

Answer 5

Classified based on number and structure of body segments and appendages, some have many segments while others have a few large body parts, insects have 3 basic segments.

Question 6

3 basic segments

Answer 6

Head, thorax (internal organs), and abdomen (posterior part of the body).

Question 7

Head and thorax fused together

Answer 7

Cephalothorax

Question 8

Respiration

Answer 8

Gills, book gills and book lungs, and tracheal tubes.

Question 9

Gills

Answer 9

Looks like a row of feathers, covered by exoskeleton.

Question 10

Tracheal tubes

Answer 10

Common in insects, uses spiracles, is a network od tubes that supplies oxygen by diffusion to all body tissues.

Question 11

Book gills and book lungs

Answer 11

Several layers of layered tissue, increases the surface are for gas exchange.

Question 12

Spiracles

Answer 12

Air enters and leaves through small openings on the side of the body which lead into the tracheal system.

Question 13

Feeding

Answer 13

Herbivores, carnivores, omnivores, parasites, filter feeders.

Question 14

Different mouth parts

Answer 14

Pincers, fangs, sickle-shaped jaws.

Question 15

Circulation

Answer 15

Open circulatory system, well developed heart and arteries.

Question 16

Excretion

Answer 16

Disposes of nitrogenous wastes using Malpighian tubes. Saclike organs extract wastes from the blood and add them to feces (digestive wastes).

Question 17

Response

Answer 17

Well developed nervous system, has a brain and sense organs.

Question 18

Sense organs

Answer 18

Compound eyes for gathering info from the environment, has more than 2000 separate lenses and can detect colour and motion.

Question 19

Movement

Answer 19

Well developed group of muscles controlled by the nervous system, cells can contract when stimulated by nerves, generates force by contracting then pulling on the exoskeleton, at each body joint the different muscles either flex or extend the joint.

Question 20

Reproduction

Answer 20

Internal or external fertilization.

Question 21

Internal fertilization

Answer 21

In some species, the males have a reproductive organ that places sperm inside the female, in other species, the male deposits a sperm packet that is picked up by the female.

Question 22

External fertilization

Answer 22

Takes place outside the females body, occurs when females releases eggs from body and males shed sperm around the eggs.

Question 23

Classification

Answer 23

Trilobita, Chelicerata, Crustacea, Uniramia

Question 24

Trilobita

Answer 24

Oldest subphylum of arthropods, lived in ancient seas, all extinct.

Question 25

Chelicerata

Answer 25

Spiders, scorpions, mites, ticks

Question 26

Crustacea

Answer 26

Crabs, crayfish, lobsters

Question 27

Uniramia

Answer 27

Millipedes, centipedes, insects

Question 28

Growth and development

Answer 28

In order to grow, all arthropods must molt their exoskeletons. The process of growth is called metamorphosis.

Question 29

Molting

Answer 29

Arthropod expands in size, old exoskeleton stretches, then hardens which can take a few hours to a few days. Most Most arthropods molt several times between hatching and adulthood.

Question 30

2 types of metamorphosis

Answer 30

Incomplete and complete.

Question 31

Incomplete metamorphosis

Answer 31

Changes from young to adult, young resembles adults but lack functioning sex organs and other adult structures (nymphs), goes from egg to nymph, e.g grasshoppers and dragonflies.

Question 32

Complete metamorphosis

Answer 32

4 stages: egg (will undergo metamorphosis), larva (looks nothing likes parents, molts repeatedly), pupa (adult structures begin to grow and larval structures break down), adult (has completely different internal and external body parts).

Question 33

Instars

Answer 33

Growth periods between molts of nymphs and larva.

Question 34

Ecological importance of arthropods

Answer 34

Source of food, 2/3 of the worlds flowering plants depend on them for pollination, symbiotic relationships.

Question 35

Symbiotic relationships

Answer 35

Plants (bull horn acacia tree and ants), other animals (fish and cleaner shrimp).

Question 36

Economical Important of arthropods

Answer 36

Agriculture, bees make honey, silkworms make silk, lobster, shrimp, crab, etc., are food, medical uses.

Question 37

Medical uses

Answer 37

Chitin from crustacean shells are used to dress wounds and make thread for surgical stitches.

Question 38

Applications being investigated

Answer 38

Chitin may be sprayed on fruit to prevent spoiling, spide venom can be pesticides, spider silk can make bulletproof vests.