Download Animals: Invertebrates

Biology 10 Lecture Outline
Chapter 30 – Animals: Part 1
I.
Overview
A. Evolution & Classification of Animals
B. Introducing the Invertebrates
C. Molluscs
D. Annelids
E. Arthropods
II. Evolution & Classification of Animals
A. Animals are in the Domain Eukarya and Kingdom __________.
Animal features:
1. Mobile, ___________ organisms
2. ___________ – usually acquire food by ingestion followed by digestion
3. ___________ – most have specialized cells that form tissues and organs
4. Have a life cycle in which the adult is usually _________
5. Usually engage in __________ reproduction and produce an embryo that undergoes
developmental stages
B. Evolution of Animals
1. The more than ___ animal phyla are believed to have evolved from a ___________
ancestor
2. In this lecture, we will examine the _____________, animals without a backbone
C. Criteria for ____________
1. Level of ______________ – includes cellular, tissues, or organ levels of organization
2. Number of _______ Layers – these embryonic layers, which include endoderm,
mesoderm and ectoderm, become specialized tissues and organs
a. Animals with no germ layers have only a __________ level of organization
b. Animals with __ germ layers (ectoderm and endoderm) have a ____________ level
of organization
c. Those with all __ germ layers have an ________ level of organization.
3. Type of _______ Plan
a. ____ plan animals have incomplete digestive systems, with ____ opening for food
ingestion and for waste disposal
b. ______ within a _____ plan animals have complete digestive systems, with
separate openings for food and waste
4. Type of ___________
a. ______________ – no symmetry, the most primitive type
b. __________ symmetry – like a wheel
c. ___________ symmetry – a cut down the center produces two equal halves; the
most advanced type
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5. Type of _________ (internal body cavity = space between digestive tract and body
wall)
a. ____________ have no body cavity (most primitive type)
b. _________coelomates have a body cavity incompletely lined by mesoderm
c. ____________ – have a body cavity completely lined with mesoderm, and can be
protostomes or deuterostomes
1) In ___________, the first embryonic opening becomes the mouth
2) In ___________, the first embryonic opening becomes the anus
6. ______________ – the repetition of body parts along the length of the body.
Segmentation leads to specialization of the parts
III. Introducing the Invertebrates
A. Animals are believed to have evolved from ___________, less specialized organisms to
__________, more specialized organisms in the following order of _________:
1. ___________ - sponges
2. ____________ - hydras, jellies, sea anemones, corals
3. ________________ - flatworms (planarians, flukes, tapeworms)
4. ______________ - roundworms
5. ______________ - snails, slugs, bivalves, squids, octopuses
6. ____________ - segmented worms (earthworms, polychaetes, leeches)
7. _______________ - crustaceans, insects, arachnids (spiders), centipedes, millipedes
8. ______________ - sea stars, sea urchins
9. _____________ - lancelets, tunicates, lampreys, fishes, amphibians, reptiles, birds,
mammals
B. __________ (Porifera) have relatively simple, porous bodies
1. Sponges are among the simplest animals; they are hollow organisms with many
_______ in their walls
2. Major characteristics of sponges include
a. Most are _________, some freshwater inhabitants that live on the bottom and are
________ (don’t move)
b. Some are radially symmetrical, some __________
c. They reproduce asexually by __________ or fragmentation
d. They are __________ feeders - feed by collecting bacteria from the water that
moves through their porous bodies and phagocytosing it
e. They lack a _________ stage during embryonic development
f. They lack true __________ and organs (no muscles, nerves, or digestive tract) but
have 3 cell ________:
1) Inner layer has flagellated _____________ (collar cells) that trap and
phagocytose food particles
2) Middle layer has
a) rigid _________ for support
b) mobile ____________ that pick up food from internal choanocytes and
digest it
3) Outer layer is __________ with flattened cells
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C. ______________ are radial animals with stinging threads
1. Cnidarians include marine jellies (______ fish), sea anemones, & _________, and
freshwater hydras
2. Major characteristics of Cnidarians include
a. They have stinging cells called ____________ within __________ capsules on
their tentacles, which they use to capture small prey
b. They exhibit ________ symmetry, which may be two types:
1) A sessile _____, which is a cylindrical body with tentacles projecting from one
end (e.g.: hydra & anemones)
2) A motile __________ shaped like an umbrella with fringes of tentacles below
(e.g.: jellies)
3) Different types of cnidarians may have one or _____ forms in their life cycles
(jellies have both)
c. They have an incomplete digestive system - a saclike body (the _____________
cavity) in which the one opening serves as both mouth and anus
d. They have a ________ stage and true __________, including nervous and muscle
tissues in some, but no true organs
D. ___________ (Platyhelminthes) are the simplest bilateral animals
1. Flatworms are ribbonlike animals that include _________ flukes & tapeworms and
______ living (nonparasitic) planarians
2.
3.
Characteristics of flatworms include
a.
b.
They are _____________ symmetrical
c.
They have limited _______ systems
____________ are free-living (nonparasitic) flatworms that live in freshwater ponds
& streams. Their features include
a.
b.
c.
d.
4.
Most have an __________ digestive tract (mouth & anus are the same opening),
and no additional body cavity
A triangular head with two ___________
A simple ____________ system
A muscular _______ on their mid-ventral surface that serves as a mouth
________ on their ventral surface and muscles allow them to crawl, twist, & turn
________ are endoparasites that must derive their nourishment inside a host animal.
A blood fluke called Schistosoma causes _________________ in humans. Their life
cycle is
a.
Blood flukes in humans reproduce __________ and their fertilized eggs pass out
in the host’s feces
b.
c.
Ciliated ________ hatch in water and enter a ________, the secondary host
___________ reproduction in the snail produces other larvae that can infect
humans
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5.
_____________ are also endoparasitic and inhabit the digestive tracts of vertebrates.
Their features include
a. Long, ____________ bodies with repeated parts
b. No _________ tract; they absorb nutrients directly from their host
c. Its head is its smallest part and has ________ and teeth that grasp the host
d. The repeated parts contain male & female _________ organs; the parts at the tail
end are filled with _____ and break off in the host’s feces
e. The tapeworm life cycle also involves more than one ______: a predator can
become infected by eating _______ that has eaten egg contaminated grass
f. Humans can become infected by several types of tapeworms, including one
obtained from eating ______ beef
E. ____________ (Nematoda = nematodes) have a complete digestive tract
1.
Roundworms are cylindrical with a tapered head and live wherever there is rotting
___________ matter.
2.
3.
They are covered by a tough, protective __________
4.
They have a ___________ digestive tract, with both mouth & anus, surrounded by a
__________coelom
Most nematodes are ______ living, but some are parasitic
a.
Free living nemotodes are important ___________ in soil and on the bottoms of
lakes & oceans
b.
___________ nematodes include those that attack plant roots, as well as
hookworms, pinworms, heartworms, etc.
c.
_____________, caused by Trichinella spiralis is contracted by eating
undercooked pork. The worm infects muscle and can cause death when in the
heart
F. Diverse ____________ are variations on a common body plan
1.
Mollusks include _______, slugs, oysters, clams, octopuses, & squids and have the
following features
a.
b.
_____________ symmetry
Three main body parts:
1) A muscular ________ for movement
2) A _________ outgrowth of the body surface that drapes over the animal, often
forming a shell and facilitating respiration, waste disposal, and sensory
reception
3) A _________ mass where the internal organs are situated
c.
Many mollusks have a rasping tongue called a _________ that is used to scrape
up food
d.
All have a ________ and a circulatory system that distributes nutrients and water
through the body
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e.
The three most diverse _____ of mollusks are the gastropods, bivalves, and
cephalopods
1) ___________ include snails & slugs and are found in both aquatic and
terrestrial environments
2) ___________ include clams, oysters, muscles, & scallops that have two shells
hinged together and are generally filter feeders
3) ____________ - include squids & octopuses
a) In most the shell is small or _________
b) they have beaklike jaws and a _____ to crush their prey
c) They have large ______ & sophisticated sense organs
G. ____________ are segmented worms that include earthworms, polychaetes, & leeches
1.
Common features of annelids are
a.
b.
c.
d.
e.
f.
2.
3.
4.
__________ symmetry
____________ body
True _________
__________ systems
A __________ digestive tract, with separate mouth & anus
__________ circulatory system
_______________ eat through soil and excrete soil improving wastes through an anus
at their posterior end. Other features
a.
b.
Organs in the repeating ____________ include excretory& nervous tissues
c.
Unsegmented main ________, dorsal & ventral blood vessels are connected by
segmented vessels, including 5 pairs of hearts
d.
They’re ____________: each has both male & female gonads
The digestive tract is _____________, passing through segment walls from mouth
to anus
______________ are mostly marine and are the largest group of annelids
a.
_____________ live on the sea floor and have segmented appendages with hard
bristles that help them to move
b.
____________ build and live in tubes from which they extend feathery
appendages to trap food particles
__________ may be free living or parasitic and live mostly in fresh water habitats and
some moist, tropical forests
a.
Parasitic leeches attach to a host, bite through the skin, and secrete saliva with an
antiseptic & ________________ components that allow them to feed on the host’s
blood
b.
Leeches are currently used _____________ to help reattach severed appendages
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H. ________________ (“jointed foot”) are the most numerous and widespread of all animals,
including lobsters, crabs, barnacles, spiders, ticks, and insects
1.
Arthropod characteristics include
a.
b.
c.
d.
e.
2.
____________ symmetry
____________ appendages
____________ body, usually composed of a head, thorax, and abdomen
_____________ composed of chitin & proteins
A true __________ with an open circulatory system
The 4 major groups of arthropods are
a.
____________ (subphylum Crustacea) are nearly all aquatic and include lobsters,
crayfish, crabs, shrimps, and barnacles; all have 2 pr. of antennae, most have
compound eyes
b.
____________ (class Arachnida) have 4 pr. legs and include scorpions, spiders,
ticks, & mites; a subphylum includes these animals and a “living fossil” called a
horseshoe crab
____________ have 2 pr. of legs per segment & Centipedes have 1 pr. legs per
segment; they resemble annelids, but have numerous jointed legs
c.
d.
_________ (class Insecta) are the largest group of arthropods and terrestrial
animals in general
I. Insects are the most ___________ group of organisms
1.
The total number of insect species is greater than all other animal species combined,
with about 1 ________ known species
2.
Common features of insects include
a.
b.
c.
d.
Most have a 3 part body (head, _________, abdomen)
e.
Many insects have one or more ________ stages and undergo _______________
in their development.
The head usually has paired eyes and _____________
_______parts are adapted for a particular type of eating
Adults usually have ___ pairs of legs and one or two pairs of ________ borne on
the thorax