Quiz 1 - Microscopes and Porifera Flashcards
Classification: What phyla, classes, or subclasses are in Porifera? (4)
Classes
- Homoscleromorpha
- Calcarea
- Hexactinellida
- Demospongiae
what is the largest class of sponges?
Demospongiae
What kind of organization does Phylum Porifera have?
cellular level only, they have specialized cells but no tissues or organs
Parazoa
possess different kinds of cells and are asymmetrical
what is the symmetry of Phylum Porifera?
asymmetrical
what skeleton or support does Phylum Porifera have?
no real skeleton, but they do have spicules and spongin
spicules
calcium carbonate/silica ‘toothpicks’ to give rigidity
what kind of movement or locomotion does Phylum Porifera contain?
they are sessile adults
does Phylum Porifera have any sensory or nervous structures?
no
what kind of digestion does Phylum Porifera have?
they only possess intracellular digestion
what kind of feeding does Phylum Porifera have?
suspension feeding
how does Phylum Porifera deal with excretion/osmoregulation?
they use simple diffusion between the environment and cells
how does Phylum Porifera handle circulation/internal transport?
they have no specialized structures, they use simple cell to cell transfer
how does Phylum Porifera do respiration/gas exchange?
they use simple diffusion with the environment
Are the members of Phylum Porifera monoecious or dioecious?
they are mostly monoecious but have some dioecious members
does Phylum Porifera use sexual or asexual reproduction?
they use both depending on the environmental conditions
asconoid body type
- simplest form
- water flows through it
syconoid body type
- intermediate form
- lots of small canals for water to move through
leuconoid
- most complex body type
- have many small passage ways to add surface area to the body allowing for larger sizes
spongoceal
the center opening of a sponge
amebocyte
mobile cells that carries food to other sponge cells and has the ability to differentiate into any other cell type (totipotent)
pinacocyte
flattened cells that collectively make up the outer sponge body wall
porocyte
doughnut-shaped cell that channels water into the radial canals
choanocyte
flagellated cells that line the interior surface of radial canals and captures food particles for the sponge
list the three body types in sponges from least to most complex
asconoid, syconoid, leuconoid
water flows into the sponge body through numerous pores on the outer surface called _____
ostia
water flows along incurrent canals, passing through other smaller openings in specialized cells called _____ into _____ _____
porocytes, radial canals
radial canals are lined with what type of cells?
choanocytes
Finally, water dumps into the _____, and is released from the sponge body through the _____
spongocoel, osculum
The amount of food needed by a sponge is going to be determined by what?
the total volume of cells in its body
Sponges have a very different body organization compared to other animals. What explains the unusual nature of sponge bodies being inconsistent with sponges being animals?
The sponge body represents a separate evolution of multicellularity from that of animals with other levels of body organization
What is A?
ocular lens
What is B?
the head
What is C?
arm
What is D?
mechanical stage
What is E?
power switch
What is F?
light intensity adjustment dial
what if G?
stage adjustment knobs
what is H?
the base
what is I?
the nosepiece
what is J?
objective lenses
what is K?
the stage
what is L?
the condenser
what is M?
iris diaphragm
what is N?
fine adjustment knob
what is O?
coarse adjustment knob
what is P?
illuminator
What is the orientation of the slide when it appears through the ocular lenses?
upside down and backwards
under which objective lens if the field of view the largest?
the lowest magnification
under which objective lens is the field of view the smallest?
the highest magnification
which lens gives you the largest working distance?
the low magnification
which lends has the greatest depth of field?
low power
As a rule, as magnification increases, depth of field _____
decreases
which level of magnification requires the most illumination for the best clarity and contract?
high magnification
If you have a microscope with a 10x ocular lens and a 40x objective lens, what is the total magnification?
400x
what kind of spicules does class Calcarea have?
calcium carbonate
what body types does Class Calcarea have?
all three, asconoid, syconoid, leuconoid
what type of spicules does Demospongiae have?
silica
what body types does Class Demospongiae have?
leuconoid
what is the only class with freshwater sponges?
Demospongiae
what type of spicules does Homoscleromorpha have?
silica and spongin, but few of them
what body types do Homoscleromorpha have?
all leuconoid
what kind of spicules does class Hexactinellida have?
silica
what body types do class Hexactinellida have?
an intermediate between syconoid and leuconoid
pinacoderm
not a tissue
outside layer of a sponge composed of pinacocytes
prosopyle
the hole through the center
Where can members of Class Calcarea be found?
they mostly occur in shallow marine waters
What Class is also called ‘glass sponges’?
Hexactinellida
In class Hexactinellida, what do their spicules do?
they are often fused together to form an elaborate skeleton
Where can members of Hexactinellida be found?
mostly in deep oceans, with a few occuring in shallow waters in polar regions
Describe the skeletal structure of Class Demospongiae.
they have spicules made of silica and have fibers made of a protein called pongin that form the skeleton
Where can you find members of Class Demospongiae?
they occur in all marine environments, and are they only class to contain freshwater sponges
where can members of Homoscleromorpha be found?
shallow marine waters, usually in caves or overhangs
Describe the structure of Class Homoscleromorpha
living sponge is a thin layer growing on a base of calcium carbonate, with few spicules made of silica and have spongin
What is special about Class Homoscleromorpha?
it is possible that their larvae have some tissue level organization!
ostium
plural ostia
name of a hole in the outside of a sponge through which water enters
spongocoel
the large central cavity of a sponge
osculum
the hole at the top of a sponge through which water exits
water flow of an asconoid sponge (3)
ostium -> spongocoel -> osculum
where are choanocytes found in asconoid sponge body types?
the spongocoel
water flow in a syconoid sponge (7)
ostium -> incurrent canal -> prosopyle -> radial canal -> apopyle -> spongocoel -> osculum
where are choanocytes found in the syconoid sponge body type?
radial canal
water flow through a leuconoid sponge body type (8)
ostium -> incurrent canal -> prosopyle -> flagellated chamber -> apopyle -> excurrent canal -> spongocoel -> osculum
what Class/Phylum does this specimen belong to?
Class Homoscleromorpha
Phylum Porifera
What Class/Phylum does this specimen belong to?
Class Hexactinellida
Phylum Porifera
What Class/Phylum does this specimen belong to?
p.c.
Class Calcarea
Phylum Porifera
What Class/Phylum does this specimen belong to?
Class Demospongiae
Phylum Porifera
