Biology Questions and Answers
cells with amoeboid movement (by
pseudopods), ththey are embedded in connectivee amoebocytes; since
matrix, amoebocytes move and
distribute nthey also produce spiculutrients to other cells andes that like a (^)
primitive skeleton fill the tissue and
support the body structure. poriferans have an internal skeleto(Some (^) n, an
endoskeleton, made of spicules and
organic fibers.)
- Concerning digestion how
are poriferans characterized?
Sponges are different from otheranimals since they present only
intracellular digestion. They do not have
a digestive systemdigestive enzymes in the spongocoel nor do they releaseto (^)
cause extracellular bnutrients. reak down of
- How are animals divided
according to their type of
digestive process?
Apart from sponges, that ddigestive cavity where extracellularo not have a
digestion takes place, all other animals
have a digestive systemcavity in which extracellular d with an internaligestion
occurs.
- How are gases exchanged
in sponges?
The gas exchange in sponges happens
by diffusion from the exterior to the
cells that absorb molecular oxygen and
liberate carbon dioxide.- Do sponges have nervous,
circulatory and excretory
systems?
Sponges do not have a nervous system
neither circulatorysystem. system nor excretory - Is reproduction in sponges
sexual or asexual?
Reproduction in by budding, gemmation osponges can ber asexual
fragmentation (rwith larval stage (a ciliatedegeneration) o r sexual
amphiblastula larva). - What is the evolutionary
advantage of the occurrence
of sperm cells and larval stage
in the life cycle of sponges?
The sexual raddition to contribeproduction in sponges, inuting to genetic
variability,colonization o also facilitatesf farther environments by the (^)
these beings, since slarvae are mobile and can swim in perm cells andthe (^)
exterior to compensate the immobility
of the adult individual.
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