Document Sample
KINGDOM ANIMALIA - PowerPoint Powered By Docstoc
                   General Info
   Of all the kingdoms of organisms, the animal kingdom
    is the most diverse in appearance.
   More than a million species of animals are known.
   Animals are grouped into about 35 phyla (mostly
   Vertebrates make up one subphylum within the Phylum
    Chordata less than 5% of all animal species.
   95% of all animal species are invertebrates and do not
    have a backbone.
   Animals carry out the following essential functions:
    feeding, respiration, circulation, excretion, response
    movement, and reproduction.
   What animals represent the majority of all animal
             What is an animal?
1.   Animals are multicellular, heterotrophic,
     eukaryotes. They take into their bodies
     preformed organic molecules, they cannot
     construct them from inorganic chemicals. Most
     do this by ingestion.
2.   Animals typically store their carbohydrate reserves
     as glycogen.
3.   Lack cell walls.
4.   Two types of tissues responsible for impulse
     conduction and movement: nervous tissue and
     muscle tissue.
5.   Reproduce sexually (most).
      Early Development (Embryology)
  Animals that reproduce sexually begin life as a zygote, or
   fertilized egg. The zygote undergoes a series of divisions to
   form a blastula, which is a hollow ball of cells. The blastula
   folds in on itself, forming a single opening called a
 The blastopore leads into a central tube that runs the length of
   the developing embryo. This tube becomes a digestive tract
   and is formed in one of two ways.
1. A protostome is an animal whose mouth is formed from the
   blastopore. Most invertebrates are protostomes.
2. A deuterostome is an animal whose anus is formed from the
   blastopore. The mouth is formed second after the anus. All
   vertebrates are deuterostomes.
   The cells of most animal embryos differentiate into
    three layers called germ layers.
   The cells of endoderm (innermost germ layer),
    develop into the linings of the digestive tract and
    respiratory system.
   The cells of mesoderm (middle layer), give rise to
    muscles and much of the circulatory , reproductive,
    and excretory organ systems.
   The ectoderm (outermost layer), gives rise to sense
    organs, nerves, and the outer layer of the skin.
                   Body Symmetry
   With the exception of sponges, every kind of animal
    exhibits some type of body symmetry in its anatomy.
   Many simple animals have body parts that repeat
    around the center of the body. These animals exhibit
    radial symmetry. (Ex. Sea Anemone, Cnidarians)
   In animals with bilateral symmetry, such as crayfish,
    only a single imaginary plane can divide the body into
    two equal halves. These animals have right and left
    sides, front and back ends, and upper and lower sides.
   The anterior is the front end, and the posterior is the
    back end. The dorsal is the upper side, and the ventral
    is the lower side.
   Animals with bilateral symmetry usually display
   Cephalization is the concentration of sense organs
    and nerve cells at the front end (anterior) of the body.
   Animals with cephalization respond to the
    environment more quickly and in more complex ways
    than simpler animals can.
   Animals with bilateral symmetry usually move with the
    anterior end forward, so this end comes in contact
    with new parts of the environment first.
             Body Cavity Formation
   Most animals have a body cavity, or coelom, which is
    a fluid filled space that lies between the digestive tract
    and the body wall.
   A coelom is important because it provides a space in
    which internal organs can be suspended. This space
    allows organs to grow and develop and protects them
    from body movements.
   In some animals, the coelom contains fluids that are
    involved in circulation, feeding and excretion.
                             Review Questions
1. What are the major characteristics that distinguish animals from plants?
2. Why is it not sufficient to classify animals simply as multicellular heterotrophs?
3. State the three germ layers found in most animals and give an example of a tissue type or organ
     system that arises from each. )
4. What conclusions can be drawn from the observation that almost all animals undergo similar
     development from zygote to blastula to gastrula?
5. A student submits a diagram of an embryo with the three germ layers labeled. The title reads
     “Diagram of sponge embryo.” Do you mark it right or wrong? Explain.
6. Distinguish between acoelomates, pseudocoelomates, and coelomates.
7. As animals became more complex, why was the development of a coelom important?
8. Describe the two types of body symmetry.
9. Which kind of symmetry has the fewest planes of symmetry?
10. Which form of symmetry is characteristic of the highest animals?
11. Explain why animals with radial symmetry show no signs of cephalization.
12. List the main body areas associated with bilateral symmetry and state what each one means.
13. Is your head anterior or posterior to your arms? Describe the location of your arms in relation to
     your shoulders.
14. “Dorsal” relates to
a) the forward or head end of an animal b) the back or upper surface of the animal
c) the lower side or belly of the animal d) the tail end or the end away from the head of an animal
15. Radial symmetry is to sea stars as bilateral symmetry is to
a) hydra b) jellyfish c) bony fish d) sand dollars

Shared By: