Biology 11
Name: _________________________ Date: __________ Block: _____
Phylum Arthropoda
(Greek: arthros = “joint”, podos = “foot”)
Pages 334-338
I Background:
- The Phylum Arthropoda is the largest phylum of all animals, with over a million described species.
- Arthropoda is divided into 5 Subphyla that include a total of 19 Classes. Some of these Subphyla and Classes include:
- Subphylum: _______________ (Includes 1 Class)
- Class: _______________ – Includes only the Trilobites, which are extint
- Subphylum: _______________ (Includes 4 Classes)
- Class: _______________ – Spiders, Scorpions, Ticks, Mites etc.
- Subphylum: _______________ (Includes 4 Classes)
- Class: _______________– Centipedes
- Class: _______________ – Millipedes
- Subphylum: _______________ (Includes 4 Classes)
- Class: _______________ – Insects – this is the largest of the Arthropod Classes, with more than half of all known living species
- Subphylum: _______________ (Includes 6 Classes)
- Class: _______________ – Lobsters, Crabs, Shrimp, Crayfish etc.
- Class: _______________ – Barnacles
- Subphylum: _______________ (Includes 1 Class)
DID YOU KNOW!!!: At least half of the described species of living animals are Arthropods (mostly insects), but arthropods are less common as fossils. The most familiar group of fossil Arthropods is undoubtedly the trilobites!!!
II Body Plan/Structure:
- Arthropods have _______________ symmetry
- They have the three true germ layers:
- _______________
- _______________
- _______________
- Defining characteristics of all Arthropods:
- The division of the body into _______________ body segments:
- The _______________ containing
- _______________ organs
- _______________ (including pinchers)
- The _______________ containing
- Walking _______________
- _______________ if present
- The _______________ containing
- _______________ organs
- _______________ in Crustaceans
- _______________ in Arachnids
- Note: The head and thorax of some Arthropods (such as the Arachnids) have fused to become a _______________
- Arthropods have an _______________ made of _______________
- Benefits of the exoskeleton include:
- _______________
- prevent _______________ (drying out)
- provide _______________for muscles
- Drawbacks of the exoskeleton: In order to grow, Arthropods have to undergo _______________ in which they shed the old exoskeleton and grow a new, larger exoskeleton.
- Arthropods have _______________ appendages adapted for :
- _______________
- _______________
- _______________
- _______________
III. Feeding
- Arthropods have a _______________digestive system, with a _____________in the head, and an _______________ at the end of the abdomen.
- Due to the incredible diversity of the Arthropods there are many different types of feeders ranging from herbivores to scavengers to carnivores.
- The Arthropod mouth is made up of two or more _______________ (modified segments) adapted for the kind of food eaten.
- Examples of some of these mouth parts:
- _______________ in the Class Insecta
- _______________ in the Arachnida
- Respiration
- There are three major forms of respiratory systems in Arthropoda:
- _______________ Aquatic Arthropods, such as the Class _______________, have gills for respiration under water
- _______________ Book lungs can be found in the Class Arachnida. Book lungs are made up of stacks of alternating _______________and _______________ tissues, which resemble a closed book. They are connected to the outside world by small openings called _______________.
- A _______________: Terrestrial Arthropods such as the Class Insecta have a tracheal system consisting of _______________ and _______________. The _______________ are small openings in the exoskeleton that can be opened and closed to allow gas exchange.
- Once oxygen has entered the _______________ it travels along the many _______________ to all of the body tissues.
- Internal Transport
- Arthropods have an _______________ made up of a large internal cavity called a _______________ that is filled with _______________ (Arthropod blood)
- Arthropod blood is used to transport nutrients to the tissues
- Arthropods also have a series of _______________ that run along the _______________ side
- The hearts pump _______________ from the abdomen to the head through the single Arthropod blood vessel called the _______________
- Once the _______________ enters the _______________ it leaves the aorta and moves into the spaces between the tissues (hemocoel).
- It then flows back to wash over the _______________ organs
- Excretion:
- Insects (and some other Arthropods) have special organs called _______________ located around the stomach
- These _______________ collect metabolic wastes from the hemocyanin and transport them into the _______________ where they mix with undigested food
- The wastes are released from the _______________
VII. Response:
- The Arthropods have a fairly large _______________in their head
- The brain controls the rest of the body by sending signals down a large _______________
- Arthropods have many specialized organs used for sensing and responding to their surroundings
- _______________
- are used to sense and respond to _______________ as well as _______________ and _______________
- _______________:
- Insects and Crustaceans have _______________
- Unlike our human eyes, compound eyes are made up of thousands of individual units that each provide a _______________of light to the brain
- The brain then interprets the array of dots of light as an image (much like the pixals of an electronic image)
- The compound eye cannot focus so the image is usually blurry and the eyes are mostly used to detect _______________
- The _______________ of some Arthropods (such as the Crustaceans) are able to detect differences in chemicals and allow them to _______________and _______________
- _______________ – Some Arthropods (such as Crustaceans and the Insects) contain special structures called _______________at the base of their antennae that give them a sense of balance
- _______________ – Some Arthropods have a membrane found on either side of the _______________ that detects sound vibrations.
VIII Movement
- There are many forms of movement seen in the Arthropods ranging from the segmental movement seen in Millipedes to the ability to fly seen in some of the Insects and to the ability to swim seen in some Crustaceans
- Due to the rigid _______________ Arthropods must have _______________ in order to move. This is how they have received their name Arthropoda, “Jointed Feet”
- Most Arthropods contain many more _______________ than humans that help them perform all of their intricate movements
IX Reproduction
- Arthropods are either _______________ or _______________ but not _______________
- In Insects the male fertilizes the female by releasing sperm into the female’s sperm _______________
- The fertilized egg is released from the female through an _______________ near the anus
- Insects have several life stages:
- The _______________
- Released from the ovipositor
- Contains the embryo
- The young insect, which may be either
- a _______________ – a young insect which more or less resembles the adult.
- or a _______________– a young insect that doesn’t resemble the adult form
- Larvae have a pupal stage during which they undergo _______________ in order to turn into adults. (Nymphs do not have a pupal stage and do not undergo metmorphosis)
- The _______________ The pupa is a nonfeeding stage following the larval stage. An example is the cocoon
- The _______________