Highest_priority_cards_9_-_all_duplicates Flashcards
Q: Describe invertebrates (general characteristics)
Animals without backbones.
Invertebrates may have some type of internal or external support.
Q: Typical reproductive strategy for invertebrates
Have mass numbers of offspring all at once, maybe only once in their life
Q: Examples of invertebrates
Jellyfish, octopi, mollusks, worms, spiders, insects
Q: Largest Phylum of invertebrates
Arthropods
Q: Meaning of Arthropoda
“jointed feet”
Q: Five major classes of arthropods
Arachnids, millipedes, centipedes, crustaceans, and insects.
Q: Arthropod characteristics
Bilateral symmetry
Hard exoskeleton
Segmented body
Paired, jointed appendages
Q: Exoskeleton
External skeleton that supports and protects an animal’s body.
Q: What are arthropod exoskeletons made of?
Chitin (pronounced kīt′n)
Q: Function of exoskeleton
Armored protection
Site for muscle attachment
Allows adjacent segments and joints to act as levers, thus improving locomotion
Has waxy coating which makes it impermeable to water and provides a resistance to water loss.
Jointed legs, acting like hinges, provide flexibility and allow for movement much like that in a medieval suit of armor.
Q: How do animals with exoskeletons grow?
Exoskeleton is hard and rigid, unable to expand and grow once formed.
Arthropods must molt (ecdysis) or shed their exoskeleton periodically.
Insects grow in spurts.
Molting is a time of vulnerability and danger and is one disadvantage of arthropod design as the new shell takes time to dry.
Q: Ecdysis
“ek-duh-suhs”
the molting or shedding of an outer layer of skin, as by insects, crustaceans, and snakes.
Q: Why are invertebrates small? (except some large marine organisms) How has this affected their adaptability to niches?
There is an upper limit to the efficient size of an exoskeleton.
Due to the lack of a sturdy, internal supportive structure, most invertebrates are small.
Small size allowed them to inhabit many more types of specialized niches than were available to a larger organism.
Q: Which animals were the first to come ashore from the oceans?
Arthropods
Q: Which animals were the first to fly?
Arthropods
Q: Features of arthropods that helped them as they evolved for life out of the water?
Hard exoskeleton prevented them from drying out
Evolved a way of getting oxygen without water by breathing air
Q: Key roles of arthropods, and especially insects in ecosystems
Vital role as decomposers of organic matter, recycling nutrients.
- Termites break down dead trees
- Many beetles help to decompose decaying animals, plants, and fungi
- Dung beetles (widespread): ground cleanup crew, fertilizes the soil, improves nutrient recycling and soil structure
Pollination of plants. (>80% of flowering plants depend on insects for pollination.)
Vital to soil aeration.
Vital role in food webs - major source of food for some birds, amphibians, reptiles, and mammals. (Especially insects!)
Control populations of pests, including other insects.
Q: Crustacean characteristics and examples
-5 or more pairs of legs
-2[/3] body regions (cephalothorax (combines head and thorax), abdomen) [slides say 2 body regions; most sources say 3, separating head from thorax]
-No wings
-2 pairs of antennae, usually
-Most have modified front legs that have oversize pincer-like claws
Examples:
-(Mostly marine, some freshwater, a few terrestrial)
-lobsters, crayfish, crabs, shrimp, barnacles, water fleas, sowbugs (pillbugs), copepods
Q: Name one way crustaceans are important to human society
Considered economically important to humans because of their large role in marine and terrestrial food chains
Q: What major food source (for whom?) are the eggs and larvae of crustaceans a part of?
Plankton.
Major food source for fish and baleen whales.
Also krill (small crustaceans), which feed on plankton, converting it to a form suitable for many larger animals such as the gray whale
Q: Centipede characteristics
-Flattened, multi-segmented body
-1 pair of legs on most body segments
-1 pair of antennae
-No wings
-Terrestrial
Q: Centipede feeding style
Most are carnivorous and predatory with modified front legs delivering venom to their prey
Q: Centipede ecological role
-Form an important item of diet for many species such as beetles and snakes.
-Consume a tremendous amount of soil-dwelling larvae.
-Their tunneling aerates the soil, allowing water and nutrients to reach the roots of plants and grasses.
-Most are forest floor dwelling and nocturnal
Q: Millipede characteristics
-2 pairs of jointed legs on most body segments
-1 pair of antennae
-Cylindrical, multi-segmented body
-No wings
-Terrestrial
