D.Sponges
Animals with backbones are called "vertebrates." Animals without backbones are called "invertebrates."
iodine
a muscular structure at the end of the developing chordate.
The first vertebrates (as far as is known) were a group of extinct*, jawless, heavily-armored fishes called Ostracaderms. *There are a few zoologists who feel that the hagfish and possibly the lamprey and slime hag are ostracaderms, but I disagree. I'm not at all sure that the hagfish and slime hag are true vertebrates.
Brain is the ability to sense and to react or we can say it is the rellay center between action and its reaction although every organism show some stimulations known as taxis but those which have well defined brain or nervous system are called CHORDATES, Well those organism which do not have brain comes under nonchordates although there is one more category which is known has hemichordates : they have under develop nervous system
sponges -apex
humans are vertebrates as hey have the vertebral column(to be more specific the notochord). u can feel your vertebral column by placing your hand on your back.the bony structure that seems to divide your back into two equal halves is nothing but your vertebral column.
chordates
Vertebrates
The presence of a notochord at some point in the organism's development is one of the characteristics that distinguishes chordates from other phyla. Without it, I'm not sure if the organism would be considered a chordate.
It depends which organism you are referring to.
a vertebrate is a living organism with a backbone and an invertebrate is a living organism without a backbone
Vertebrates are those that have a skeletal system.
A living organism with a segmented backbone is a vertebrate.
Vertebrates are those that have a skeletal system.
because it is an organism
Yes. Multicellular means an organism has more than one cell. Kangaroos are vertebrates and all vertebrates are multicellular.