The skeleton of an embryo is made up of cartilage and collagen
Hope this helps :3
The answer is speciation by geographic isolation. When the population of a species gets separated due to reasons such as continental drift, mountains, canyons, etc. then each separated group of population may survive and adapt to their respective environment leading to speciation. These barriers do not allow the evolving populations to interbreed initially and over time when they evolve into different species they become completely reproductively isolated.
Synchroniser switch is in the "on" position.
Answer:
First, the zygote becomes a solid ball of cells. Then it becomes a hollow ball of cells called a blastocyst. Inside the uterus, the blastocyst implants in the wall of the uterus, where it develops into an embryo attached to a placenta and surrounded by fluid-filled membranes.
The epidermis is the outermost layer of skin and is app. .005-1.5mm thick. it is made up of several different types of cells with keratinocutes being the most abundant.
The dermis is the second layer of skin and is app. .3-3.0mm thick. And basically consists of connective tissue.
