bio lab 5: invertebrates Flashcards
what characteristics do all animals have in common
- they are multicellular eukaryotes
- they are heterotrophs that ingest other organisms for nutrients
- They are capable of some form of locomotion at some stage in their life
- most have 4 kind of tissues: epithelial, connective, muscle and nervous tissue
- The multicellular stage in any animal’s life is diploid. Muticellular stage in Fungi is haploid and every plant has both multicellular haploid form and a multicellular diploid form
protostome vs deuterostomes
protosome is when the mouth is the first part of the digestive system to form
deuterostome is when the anus develops first
radial symmetry vs bilateral symmetry
object with radial symmetry can be cut vertically through the middlein many ways producing two halves that are mirror images
object with bilateral summery can be cut in half in only one plane, producing two halves that are mirror images
what is segmentation
the repetition of similar units
what is cephalization
having a definite head
what is an exoskeleton
a skelteon outside the body which results in molting
what is an open circulatory system
(a vessel carries blood
part of the way through the body but then ends, allowing the blood to find its own way
back between cells or through body cavities)
what is a closed circulatory system
when blood is confined to vessels
what are the different types of digestive anatomy
Sac-like with one opening for both entrance of food and exit of wastes. Such a digestive cavity, which is usually highly branched, is known as a gastrovascular
cavity.
b. A tube-within-a-tube; has a separate entrance for food and exit for wastes. The
specimen usually contains an intestine.
what is phylum Porifera? describe them
Phylum Porifera are the animals called sponges. Sponges are made up of a collection of
cells that are arranged into poorly organized tissues. Although some members of Porifera
appear radially symmetrical, most are asymmetrical.
No true tissues
Most members of Porifera are marine, but some do live in freshwater. Examine the
specimens on display, keeping in mind that living sponges are often brightly coloured -
orange, purple, yellow, and lavender for example. These colours fade upon preservation of
the specimen.
Using the chart and diagrams of the typical sponge, locate the osculum, the central cavity
or spongocoel, the pores (incurrent canals) and the collar cells or choanocytes.
Describe how a sponge filters water to obtain its food.
- Water Flow: Water enters the sponge through many small pores on its surface. These are like tiny doors called ostia.
- Filtering: Inside the sponge, special cells called choanocytes (collar cells) use their whip-like tails (flagella) to create a current that pulls water through the sponge.
- Capturing Food: As water flows through, the choanocytes trap tiny food particles, like plankton and bacteria, using sticky structures around their tails.
- Water Exit: After the sponge extracts the food, the filtered water leaves the sponge through a large opening called the osculum.
In short, the sponge works like a natural filter, drawing in water, capturing food, and letting clean water flow out.
what is the function of choanocytes
they are cells that have flagella that create the active pumping of water through sponge while the collars fo choanocytes are the primary area that nutrients are absorbed into the sponge
what size of material can be obtained and digested by sponges
bacteria smaller than 0.5 microns
what are spicules and what are their function. What do they look like
The body of the sponge may have a tough protein framework or numerous needle-like
spicules embedded deep within it to add structural support for maintaining its shape and
keeping pores open for water flow. The spicules are composed of silica or calcium
carbonate. Observe the slide of spicules on the side bench and make a drawing of a few of
them.
spiny star shaped structures
what are some examples of phylum cnidaria? and what type of symmetry do they have
corals, jellyfish, sea whips
they have radial symmetry
describe cnidaria. What two types are they
Cnidarians organize their cells into true tissues. The basic cnidarian body plan is simple,
consisting of a gastrovascular cavity surrounded by two cell layers. Two variations on this
plan occur, the polyp (attached to a solid substrate) and the medusa (free swimming).
what is the advantage of a gastrovascular cavity over animals that lacks one (like a sponge)
increased surface area for nutrient absorption and diffusion
describe cnidocytes and nematocytes
Tentacles armed with stinging cells (cnidocytes) containing nematocysts are in a ring
around the single opening into the gastrovascular cavity. Nematocysts are unique to Phylum
Cnidaria. Study the demonstration slide of a Hydra tentacle. Observe the triggers for
nematocysts protruding from the tentacle. Draw and label the nematocysts on a tentacle.
what is this
cnidocyte
what is the function of a nematocyst
mainly to capture prey and use as defense but also for locomotion
what is the phylum for flatworms called (know how to spell)
Platyhelminthes
describe Phylum Platyhelminthes
Members of Phylum Platyhelminthes, also known as flatworms, are bilaterally symmetrical
and show protostome embryonic development. This phylum includes both free-living and
parasitic subgroups. Parasitic examples include flukes and tapeworms. Flatworms can
range in size from 1 mm to several meters in length. Examine the preserved specimens on
the side bench.
very much look like flat worms
Does the Planaria have external evidence of a definite head or sensory organs
(cephalization)?
yes, they have an obvious head region and eye spots
where does food enter in the digestive tract of a planarian? is there a separate exit for large indigestable wastes?
suck food through pharynx into gastrovascular cavity
no, food goes in and out of pharynx
how does digested food get to all part of the body in planarians
nutrients diffuse to internal tissues
planarian gastrovascular cavity
what is this
planarian. note the solid - tissue filled region outside of the gastrovacular cavity
do Planaria have an internal body cavity that contains the internal organs
no
coelem vs acoelmate
The absence of a body cavity (known as a coelom) is one of the unique features of the
Platyhelminthes. They are described as being acoelomate.
describe phylum Mollusca (SPELL LIKE THIS ON LAB EXAM). What are some ecamples
phylum Mollusca is remarkable in that its members have been shaped by evolution into a
great diversity of body forms. All are bilaterally symmetrical at some point in their
development and show protostome embryonic development.
clams, snails, slugs, squid, octopus
what unique features do most members have in common
mass of soft flash that covers soft body and encloses internal organs called visceral mass
Many of the organs inside a mollusc are suspended within a fluid-filled body cavity, called a
coelom. What advantages are offered by such an arrangement vs. a solid body, as seen in
the flatworms?
permits them freedom of movement
What other major anatomical development appears in the Mollusca that was absent in the
previously described phyla?
presence of a complete one way digestive tract and circulatory sytem
What advantage does a one-way digestive tract have over a gastrovascular cavity?
allows for specialized regions with specialized functions. also allows for continuous eating
which of the mollusks are fat-moving predatory animals and which are slow moving or sedentary filter feeders
fast: octopus, squid
slow: mussels, land snails, marine snail
circulatory sytem of fast vs slow mollusks. other features
fats: have close, slow have open
fast have well, developed tentancles and slow have shell for protection
what is this
radula of molluscs helps scape up algae to eat
why is there a close evolutionary relationship between mollusca and annelids
Many marine molluscs and marine annelids have a ciliated larva called a trochophore larva.
This indicates a close evolutionary relationship between Mollusca and Annelida.
what is the worm phylum called (spelling). Describe them
Annelida
Earthworms, leeches, bristleworms, and tubeworms are all annelids. One of their defining
features is a segmented body with some organs repeated in each body segment. Because
of this, Phylum Annelida are also known as the segmented worms. They may be found in
terrestrial, marine, or freshwater habitats.
circulatory system of annelids
closed circulatory system
di annelids have a body cavity
yes
earthworms are reciprocal hermaphrodites what does this mean?
the can potentially share resources available for reproduction between its male and reproductive system
crop function in annelids
stored food until matter goes into gizzard
gizzard function in annelids
grinds up food and begins the digestion process
intestine function annelids
food broken down into usable chemicals which are absorbed in bloodstream
clitellum function annelids
stores the eggs
spermathecae in annelids
stores sperm
seminal vesicles in annelids
produces sperm
describe phylum Nematoda
Members of Phylum Nematoda, also known as the round worms, thrive in virtually every
habitat on the planet, from deserts to glaciers. They are especially common in wet soil, and
many are parasites in plants or other animals. They are typically less than 1 mm in length,
but a 9 m parasite has been found in the placenta of a sperm whale. Animal groups with tiny
bodies are often missing some of the organ systems of larger creatures, including systems
involved in respiration and excretion (the removal of nitrogenous wastes). Instead, they
simply exchange materials across their body wall.
Nematodes are covered by a tough cuticle, which is shed (molted) periodically as the
animal grows.
Both the nematodes and the Annelids are “worm shaped”. What is one striking difference in
the morphology of the two groups?
annelids have more specialized sections
what phylum are vinegar eels
phylum Nematoda
describe Phylum Arthropoda
You are certainly familiar with this phylum. Insects, spiders, crabs, shrimps, and barnacles
are all arthropods. Approximately two-thirds of all named species on the planet are
Arthropods. They have segmented bodies, but the segments are often fused into distinct
body regions. They have an exoskeleton, and molt periodically.
what are characteristics all arthropods share
exoskeleton, bi-lateral symmetry, joined appendages, segmented bodies and specialized appendages
what kind of circulatory system do phylum Arthropoda have
open circulatory system
examples of Phylum Arthropoda
insects including butterflies and beetles, also millipededs
Take special note of the different arthropod appendages. What feature do they have in
common?
Appendages are often well adapted to a particular function. List and describe at least five
adaptations.
most segments have a pair of attatched joined appendages
- grasshopper legs for jumping, spider legs well suited to grapsing delicate webs,
wings for flying
What are some problems created by an external skeleton, and how are they solved?
limits size and movement molt to grow
why are we related to phylum echinodermata
we are both deuterosomes with endoskeletons
what are Echinodermata. Describe it
starfish
Included in Phylum Echinodermata are the sea stars, sand dollars, sea urchins, sea
cucumbers, brittle stars, and feather stars. All are marine. Echinoderm larvae have bilateral
symmetry, but most adults have pentaradial symmetry, i.e., a tendency for body parts to
come in multiples of five. Echinoderms are most closely related to Phylum Chordata (the
one that includes humans); both groups show deuterostome embryonic development.
describe the endoskeleton of echinodermata
Most echinoderms have a meshwork of small calcareous plates embedded in the tissue of
the body wall. Because this supportive structure is within the body, it is known as an
endoskeleton. Some of these plates may fuse to produce numerous movable and
immovable calcareous spines. The phylum name, translated as ‘spiny skin’, refers to this
feature.
