Arthropods Flashcards
What is the zoological classification of the house mosquito?
Animalia Arthropoda Insecta Diptera Culicidae Culex pipiens
5 characteristics of arthropods
1) Bilateral symmetry – 2 matching sides
2) Segmented body - segments may form larger functional units
3) Hard external skeleton of chitin – tough, flexible Protection, leverage, prevents moisture loss, limits growth
4) Jointed limbs – allow movement and flexibility, specialized
5) Many pairs of limbs
5 major arthropod classes
1) Crustacea – shrimp, lobsters, crawfish
2) Diplopoda - millipedes – 1,000 leggers
3) Chilopoda - centipedes – 100 leggers
4) Arachnida – ticks, mites, spiders, daddy longlegs, scorpions
5) Insecta – insects
5 facts about the class Crustacea (crayfish, pillbugs, shrimp, lobsters, …)
1) 2 pairs of antennae
2) 2 main body regions
3) Several prs walking legs
4) Scavengers, some are predators
5) Mostly aquatic & marine
5 facts about the class Chilopoda - centipedes
1) 1 pair antennae
2) 2 body regions - head and trunk
3) 1 pr long legs per segment –
1st segment – fangs, others are legs
4) Flattened body – long legs
5) Terrestrial predators
5 facts about the class Diplopoda - millipedes
1) 1 pair antennae
2) 2 body regions – head + trunk
3) 2 pairs short legs / segment
4) Cylindrical body
5) Terrestrial scavengers
5 facts about the class Insecta – flies, lice, etc.
1) 1 pair antennae
2) 3 main body regions
3) 3 pairs of legs
4) May have wings as adults
5) Mostly terrestrial – many feeding strategies
4 facts about the class Arachnida – ticks, mites, spiders, scorpions
1) No antennae
2) 4 pairs walking legs
3) 2 main body regions – may look like 1
4) Mostly terrestrial – predators, parasites, herbivores, etc.
Populations or groups of organisms that actually or potentially interbreed in nature and produce fertile offspring.
Biological species
Groups of closely related species that look almost identical but are reproductively isolated
Species complex
Ex: house mosquito complex
4 advantages of exoskeleton
1) Protection
2) Modification
3) Prevent water loss
4) Strength, leverage
2 disadvantages of exoskeleton
1) Limits growth, senses, size
2) Little ability to repair damage
Which body region is the least changed part of the body?
Head
The head has _____ fused segments and is a great way to ID a bug.
6
Antennae are used for what sense(s)?
Smell & taste
Palps are used for what sense(s)?
Taste
Compound eyes are used for what sense(s)?
Sight
Feeding - mouthparts chewing or sucking
5 mouthpart types…
1) Chewing – grasshopper, beetle
2) Rasping
3) Blotting – house fly
4) Piercing sucking – mosquito
5) Slicing – horse fly
Thorax has _____ fused segments
3
Head and thorax region of some arthropods is fused into one area called the _____.
Cephalothorax
5 Thorax facts
What makes up the thorax?
1) Strong box for wing muscles
2) Transportation center - Walking / flying (insects only)
3) Legs usually 6
4) Wings on 2nd or 2nd & 3rd segments
5) Walking, holding, manipulating
6 Abdomen facts:
How many segments?
What is within the abdomen?
1) 8 to 10 segments
2) Reproductive organs
3) Digestive tract
4) Malpighian tubules (kidneys)
5) Egg laying devices
6) Fat storage
What do arthropods use for sight?
Compound eyes - many lenses packed together
Ocelli – simple lens
What do arthropods use for smell?
Chemical detection – antennae
What do arthropods use for hearing?
Some feel vibration from setae (hairs) or thin spots on exoskeleton
What do arthropods use for taste?
Palps (part of mouthparts), taste receptors on feet, etc.
What do arthropods use for touch?
Sensory spines (setae) that bend
Molting allows _____, includes shedding of old _____, expansion and hardening of new one
Growth; exoskeleton
Molting is…
Controlled by hormones
Molting uses _____ or _____ to expand.
Blood pressure or air to expand
Metamorphosis is a change in _____. What are the two types? Give the stages each type entail.
Form
Gradual - Egg, Nymphs, Adult
Complete - Egg, Larvae, Pupa, Adult
Specialized larval types – maggots, white grubs, wrigglers, mealworms, …
Describe the arthropod’s nervous system
Decentralized - nerve cord with ganglia in each segment
Describe the arthropod’s circulatory system (3)
1) Open circulation, open-ended tubular heart
2) Blood (hemolymph) carries nutrients, waste, hormones, etc. – not O2
3) Easy movement of pathogens inside arthropod
Describe the arthropod’s respiratory system (3)
1) Openings in exoskeleton (spiracles) and tubes (trachea) direct to cells limits size of arthropods
2) Gills or breathing tubes
3) Direct gas exchange - absorb through exoskeleton when small – limits size
Describe the arthropod’s excretory system (2)
1) Tubes connected to gut - remove wastes
2) Eliminate excess water – important for many
blood feeders
Describe the arthropod’s digestive system
Long tubular intestinal track, often dealing with liquids – depending on diet
Arthropods have important roles in the food web, they are…
Herbivores, predators, decomposers
Arthropods are the most successful animals on earth because… (List 5 things)
1) Small size – need few resources
2) Short life cycles – many generations per year
3) Many adult insects have wings
4) Metamorphosis
5) Very high reproductive potential
3 exoskeleton layers
1) Outer‐ shed
2) Inner‐ dissolved
3) Bottom – forms new
