Chapter 2 Animals-Section 2 Flashcards
What are the four major groups of arthropods?
Crustaceans, arachnids, centipedes and millipedes, and insects.
What are the four characteristics of all arthropods?
1) invertebrates
2) external skeleton
3) segmented body
4) jointed attachments called appendages
What are three examples of appendages?
Wings, mouth parts, and legs
What are arthropods named for?
Jointed appendages
What are three other characteristics of arthropods that other animals share as well?
1) bilateral symmetry
2) Open circulatory system
3) digestive system with two openings
4) reproduce sexually
What is the waterproof, waxy outer skeleton that covers an arthropod called?
Exoskeleton
What is the function of the exoskeleton?
It protects the animal and helps prevent evaporation of water to keep the arthropod from drying out.
As an arthropod grows larger it’s exoskeleton cannot expand. The process of shedding an outgrown exoskeleton skeleton is called what?
Molting
After an arthropod has molted what is it’s new skeleton like? Why is this important?
It’s new skeleton is soft and the arthropod has less protection from danger then it does after its new skeleton has hardened.
In some groups of arthropods, several body segments become joined into what?
Distinct sections
An arthropod may have up to how many sections? And what are they?
An arthropod may have up to three sections. A head, a midsection, and a hind section
What do the joints in the appendages of an arthropod do?
The joints in the appendages give the animal flexibility and enable it to move.
Arthropod appendages tend to be highly specialized tools. What are they used for?
Arthropod appendages are used for moving, obtaining food, reproducing, and sensing the environment.
What is an appendage attached to the head of an arthropod that contains sense organs called?
Antenna….and most arthropods have them!
Scientists have identified more species of arthropods than all other species of animals combined. How many have they identified?
Over 1 million
Where do crustaceans live?
Freshwater lakes and rivers, oceans, coastlines, and even damp places on land.
How many body sections, pairs of legs, and pairs of antenna, do crustaceans have?
They have two or three body sections, five or more pair of legs, and two pair of antennae
What are the two pair of antennae on a crayfish used for?
They are used for smelling, tasting, touching, and keeping balance.
What are the crayfish’s first pair of legs called and what do they do?
Chelipeds and they are used for obtaining food and defending itself
Because crustaceans live in watery environments, most have gills. What is the function of the gills and where are the gills located?
Gills obtain oxygen and are located beneath the shell of the crustacean. Water containing oxygen reaches the gills as the crustacean moves along in its environment
Crustaceans obtain food in many ways. Give three examples.
1) scavengers that eat dead plants and animals
2) predators eating animals they’ve killed
3) some are herbivores
What are some examples of crustaceans?
Shrimp, crabs, crayfish, lobsters, krill, barnacles.
What is a process in which an animal’s body undergoes dramatic changes in form during its lifecycle called?
Metamorphosis
How many body sections, pairs of legs, and pairs of antenna, do arthropods have?
Arachnids have two body sections, four pairs of legs, and no antennae.
What is included in the first body section of an arachnid?
The first body section is a combined head and midsection.
What is the hind section of arachnid called? And what is contained in it?
The hind section is called the abdomen. The abdomen contains the reproductive organs and part of the digestive system.
Give some examples of arachnids
Spiders, mites, ticks and scorpions
Are spiders predators? And what do they eat?
Yes, most of them eat insects
How do you spiders catch their prey?
Some run down their prey, and others spin sticky webs to trap their prey.
Spiders have hollow things, what are they used for?
They are used to inject venom into their prey.
How does spiders venom help them to eat their prey?
Spider venom turns the tissues of the prey into mush. Later the spider uses it’s fangs like drinking straws and sucks in the food.
True or false
Spiders rarely bite people
True
Where do mites live?
Dry areas, freshwater, oceans
What are two examples of mites
Chiggers and ear mites
What do you mites feed on?
Mites feed on dead skin and hair. They are parasites.
What type of climate do scorpions live in?
Hot climates
Where can you find a scorpion during the day?
During the day, scorpions hide in cool places, such as under rocks and logs, or in holes in the ground. They are usually active at night?
How do you scorpions catch their prey?
Scorpions have a spine like stinger at the end of their abdomen. The scorpion uses the stinger to inject venom into its prey.
Where do you ticks live?
Ticks are parasites that live on the outside of a host animals body
What type of ticks attack humans? And what disease do they carry?
Infected deer ticks can spread Lyme disease.
How many body sections, pairs of legs, and pairs of antenna, do centipeds and millipedes have?
Centipedes and millipedes have two body sections, many pairs of legs, and one pair of antennae
How did centipedes get their name?
Some centipedes have more than 100 segments. The word centipede means “100 feet”.
What are the two body segments on a centipede?
Centipedes have two body sections. A head and a long abdomen with many segments.
How many pairs of legs are attached to each segment of a centipede?
Centipedes have one pair of legs attached to each segment?
How do you centipedes catch their prey?
Centipedes are swift predators that inject them into their prey
How many segments do millipedes have? And how many pairs of legs on each segment?
Millipedes may have more than 80 segments and have two pairs of legs on each segment
What do millipedes eat?
Most millipedes are scavengers the graze on partly decayed leaves.
What do millipedes to do when they are disturbed or feel threatened by a potential predator?
Millipedes can curl up into a ball, protected by their tough exoskeleton. Some will also squirt an awful smelling liquid at a potential predator.
