Transcript Chapter 9(1)

Chapter 9
Sponges, Cnidarians, and Worms
7th Grade Life Science
Structure of Animals
• ______
- basic unit of structure and function
Cell
in living things
tissue
• ________
- a group of cells that perform a
specific function
organ
• _________
- tissues combine to form an organ
which performs a more complex function than
the tissues alone
• ______
systems - groups of organs that perform the
broadest functions in animals
Functions of Animals
• Animals vary in the following ways:
size
– _________
Body structure
– ____________
Outward appearance
– _________________
– ________________________
Environment that they inhabit
diversity animals carry out the same basic
Despite _________
functions of life such as:
____________________
Obtain food and oxygen
____________________________
Keep internal conditions stable
_____________
move
______________
reproduce
Adaptations
• ___________
- structures or behaviors that allow
adaptations
animals to perform the basic functions of life
• ________________
Obtain food and oxygen - some animals have fangs or
claws that allows them to obtain food. Food is
digested and used for energy. Oxygen is either
obtained from air or water
Keep internal conditions stable
• ______________________animals must
maintain a stable environment within their
bodies to survive. Ex. Animals in hot
environments have adaptations to keep their
bodies cool.
Movement and Reproduction
• __________
movement - related to meeting the basic needs
of survival and reproduction. Most animals move
freely from place to place throughout their lives.
Others move during different stages of their lives.
• ___________
reproduction - animals must reproduce to
prevent the species from extinction
Sexual reproduction - new organism develops from
– _________________
the joining of an egg and sperm cell during
__________
fertilization
– __________________
Asexual reproduction - a single organism produces a
new organism identical to itself. Ex. Sea Anemones
Classification of Animals
• __________
species of animals have been
1.5 million
identified
classifying - sorting animals into categories
• ________
diversity
helps biologists make sense of ________
phylum
• _______
- major groups of animals – there
are about __________
currently
35 groups
• ________
- are arranged like branches on a
phyla
tree – this shows the relationships between
the major groups
Classification continued
• Animals are classified according to how they
are _____
related to other animals
• These relationships are determined by:
The animals body structure
– ______________________
– ______________________
The way the animal develops - its life cycle
The animal’s DNA
– _________________
Vertebrates / Invertebrates
Vertebrates
• ___________
- animals with a backbone
• ALL VERTEBRATES ARE CLASSIFIED IN ONLY 1
PHYLUM
Invertebrates - animals without a backbone
• __________
• ALL INVERTEBRATES ARE IN DIFFERENT PHYLA
97 percent
• _________
of all animals are invertebrates
Section 1 Assessment
Writing In Science
Animal Symmetry
Symmetry
• _________
- the balanced arrangement of
parts
Bilateral symmetry - one line that divides the
• ____________
object into halves that are mirror images
Radial symmetry
• ______________
- many lines of symmetry
that all go through a central point
sponges
• _________
- have no symmetry
Symmetry and Daily Life
simple
• Animals without symmetry have _______
body plans.
• Animals with bilateral symmetry or radial
symmetry have ________
body plans.
complex
• Animals with the same ________
symmetry share
general characteristics
• Animals with ___________
Radial symmetry do not have
distinct front or back ends
Animals with Radial Symmetry
Sea stars
Sea urchins
• Examples: ________,
_________,
and
_______
jellyfishes
back
• No distinct Front
_______ or _______
Live in water
• All _______________
• Do not ____________
Move very fast
• Movement = ___________,
______________,
Stay in one spot Creep
along the bottom
or ___________________
Are moved by water currents
Animals with Bilateral Symmetry
•
•
•
•
•
•
_______
humans have bilateral symmetry
________
and ____________
larger
More complex
________
Front end which typically goes first as it moves
Movement is quicker
_______ and ____________
More efficient
___________
body
Streamlined
___________
Sense Organs in the front end that pick up
information about what is in front of them
• ____________
Swift movement and __________
Sense organs help animals
with bilateral symmetry obtain food and avoid
predators
Assessment Questions
Sponges
• Live all over the world, mostly in _______
but
oceans
also in ______________
and ________.
Freshwater rivers
lakes
Water currentsFront carry food and oxygen to the
• _____________
sponges and take away waste products
• Water currents also play a role in __________
reproduction
and _________
young to new places.
transport
• Sponges are __________
invertebrates with _____________
No body symmetry
or _____________
Tissues or organs
Sponges continued
• Sponges have _____
and _________
that
cells
structures
perform different functions such as ______
spikes
pores
and _______
• ________
allow the sponge to remain upright
spikes
and defend itself against predators
• ________
- help move oxygen and nutrients
pores
into the sponge
• Sponges reproduce both _______
______
asexually and sexually
Obtaining Food and Reproduction
Single celled organisms by
• A sponge eats tiny _______________
filtering them out of the water.
• _____
in the sponges body trap the food and
cells
digest it
• _________
moves through the sponges
oxygen
_______
and into its ______.
pores
cells
• _______
budding is one form of asexual reproduction
Sperm
Egg cells
• Sponges produce both ______
and _________
Cnidarians
• ____________
- jellyfish, sea anemones, and
Cnidarians
corals
Stinging cells
• Cnidarians use ___________
to capture food
and defend themselves
Body plans
• Cnidarians have two different _________
• _______
- vase shaped body plan – sea
polyp
anemone
medusa
• ________
- bowl shaped body plan jellyfish
Obtaining food and Movement
Stinging cells
• ____________
are released from the
cnidarians into their prey – some have venom
• Once the prey has been stung, the cnidarians
use their _______
tentacles to pull the prey into its
mouth
• Cnidarians can move to __________
Escape danger and
_________
Obtain food - muscle-like tissues allow
movement such as swimming and stretching
Reproduction
• Cnidarians reproduce both _________
and
sexually
asexually
__________
budding
• _________
- most common form of asexual
reproduction
sexes
• Some species have both _______
in one
individual
• Some species such as the jellyfish have
__________
that include both sexual and
Life cycles
asexual reproduction
Colony
• _________
- a group of many individual
colony
cnidarians
Coral reef
• ____________
- built by cnidarians when a
coral polyp attaches itself to a solid surface
such as a broken shell, sunken ship, or rock.
• The _________
Coral polyp reproduces asexually and then
the offspring reproduce asexually.
• Coral reefs are home to more __________
invertebrates
species than any other environment on Earth
Section Assessment
• Page 311 (1-3 ALL)
Classification of Worms
• Biologists classify worms into three
major_____
phyla
1. ____________
- Platyhelminthes phylum – long
flatworms
flat bodies
2. _____________
- Nematoda phylum – long,
roundworms
round bpdy
Segmented worms - Annelida phylum – long,
3. _______________
round body made up of linked segments
Refer to the phylogenetic tree on page 298
Characteristics of Worms
Body Structure - all worms are ____________
invertebrates
1. ___________
• All worms have ______________
- head and
Bilateral symmetry
tail ends with organs, tissues, and body
systems
2. ____________
- worms are the simplest
Nervous system
organism with a brain
• Worms have __________
Sense organs that enable them to
detect objects and food and respond quickly
Reproduction
3. __________
Reproduction - both asexual and sexual
reproduction are found in the worm phyla.
• Some species of worms have both
Male and female sex organs
___________________
• Asexual reproduction occurs when worms
break into pieces and new worms grow out of
each piece
• Other species of worms have
Male and female individuals
__________________
Flatworms
• Flatworms include :
tapeworms
– ____________
- parasitic and free living varieties
– _____________
- free-living, scavengers
planarians
– ____________
- parasitic
flukes
Many flatworms are _________
- an organism that
parasites
lives on or inside another organism
Parasites take food from their _____
host
The host becomes weak and injured but rarely killed
by the parasite
Flatworms continued
• Flatworms that are not parasites are
_______________
Free-living organisms - they do not live on or in
another organism
• Free-living flatworms are found in wet
environments such as ___________________
Ponds, streams, and oceans
• __________are
free-living flatworms
planarians
• Planarians are _________
- feed on dead or
scavengers
decaying material
Planarians
• Planarians are also _________
to smaller
predators
animals than themselves
• Planarians feed like a ________________
“vacuum cleaner”
• Planarians glide onto their prey and insert a
__________
- digestive juices flow out of the
Feeding tube
planarian through the feeding tube into the
food.
• The digestive juices break down the food
________
of the worms body
outside
Planarians continued
The food is sucked into the feeding tube and
digestion is completed inside the worm’s body
in a _________
cavity
Undigested food exists the worms body through
the _________
Feeding tube
• ___________
- located in the head of the
eyespots
planarian
• Eyespots can detect ______
but cannot see a
light
detailed image
Tapeworms
tapeworms
• _____________
body is adapted to
___________
food from the _______
digestive
absorbing
hosts
system
• Many tapeworms live _______________
In more than one host in
their lifetime
• Life cycle of a tapeworm page 317 – Figure 22
Roundworms
• Live in any ________
environment
moist
• May be the most _________
animals on earth
abundant
• Some species are _________
and others are
Free-living
parasitic
_________
• ___________
bodies
cylindric
• Digestive system is _____________
Open at both ends - food
enters through the mouth and exists through
the anus
Roundworms continued
One way digestive system
• __________________
is efficient
• Food enters and is digested in an orderly
fashion
• Food is broken down by ___________
Digestive juices
• Food is then __________
into the animals
absorbed
body
• ________
are eliminated through the anus
wastes
• A large amount of nutrients can be absorbed
Segmented Worms
Body Structure
• ______________
• _______________
Circulatory System
Segmented Worms continued
Earthworms
• ____________
• __________________
Structure of an earthworm
Section 4 Assessment