dont be scared
today we are talking about?
CNIDARIA
how many layers are in hydra?
There are two dermal layers in hydra: ectoderm and endoderm
how and where medusa swim?
These swim freely in the water
how we call scyphozoa in daily life?
Jellyfish
how cnidarias get their name?
These animals get their name from their stinging cells!, called cnidocytes
where cnidarians live?
They live solitarily or in colonies
can some groups have and medusa and polyp ,so both of them?
yes
how % water jellyfish contains?
They are jell-like: 96% water by weight.
how many species are in cnidarians group?
There are over 10,000 species in this group
two forms of cnidarians
Polyp and Medusa
where do hydras live?
they live in streams, ponds and lakes
how anthozoas reproduce?
They usually reproduce sexually. A planula larva attaches itself to a hard surface, and a colony develops by budding
from greek language cnidarians means?
from a Greek word meaning "sea nettles"
3 classes in the phylum Cnidaria
•Hydrozoa
•Scyphozoa
•Anthozoa
by what does hydras reproduce asexually?
They reproduce asexually by budding or regeneration
why is important the role of photosynhetic symbionts of corals and algae?
Photosynhetic symbionts of corals and algae play an important role in the development of coral reefs.
in how many ways can cnidarians reproduce?
Reproduction in Cnidarians: They can reproduce either asexually or sexually.
How Cnidarians move?
The contractile cells in the epidermis and endodermis provide movment. The cells, together with the water filled gastrovascular cavity, form a hydrostatic skeleton that supports the body and allows movement by contracting and relaxing. So the cnidarian can shorten, lengthen, or bend its body.
how many jellyfish we have and in what shape are they?
They have nearly 200 species and all are umbrella shaped, mostly pelagic
tell me a fun fact about cnidarians
good job!