Answer:
models are universal. option A
Embryonic stem cells are pluripotent cells that are derived from the inner cell mass of a blastocyst before implantation. These cells have potential of treating a wide range of diseases and conditions, which is attributed to the fact that they have; self renewal property meaning that they can ploriferate indefinitely, the cells also have the special ability to differentiate into cells with specialized characteristics and functions. In addition the cells are unspecialized and therefore they can give rise to specialized cells.
Answer:
The respiratory system is made up of the organs involved in the interchanges of gases. It consists of the:
Nose
Mouth
Throat (pharynx)
Voice box (larynx)
Windpipe (trachea)
Airways (bronchi)
Lungs
Because the organism is distributed across the world, and isn't seen anymore, scientists can conclude tat they must have evolved. They can compare one species to the fossils they may have found, and determine that they were related. Then by looking at the species on another part of the world compare the same fossils to other animals and determine that they are similar, sharing a common ancestor.
1) They are cold blooded
2) They respire both by Skin and lungs.
3) They lay eggs in water ; they have a 3 chambered heart.