-Presence of jointed appendages and gills, lungs, jaws.
-Presence of a chitinous external skeleton or exoskeleton that change periodically.
-Body constituted by repetitive segments, phenomenon known as metamerism<span>.</span>
<span>I hope this help,</span>
<span> Sebastian Goicoechea.</span>
Answer:
C). Seafloor spreading.
Explanation:
Paleomagnetism is characterized as the 'study of the account of direction and strength of magnetic fields of the Earth in sediments, rocks, etc.' The hypothesis that was authenticated by using this study would be 'seafloor spreading' by displaying that magnetic reversal as strips of rotating polarity in gradually disseminating seafloor. This description of magnetic stripping by employing paleo-magnetism made the scientists believe that alternate crusts are being frequently made under ocean/sea. Thus, <u>option C</u> is the correct answer.
Answer:
Fossils closer to the surface are younger
Explanation:
Listed under are the 5 different type of cells found in the epidermis and their description:
1. Stem cells
These are what you call undifferentiated cells. These are cells found in the stratum basale, which is the deapest layer of the epidermis. These cells divide to create keratinocytes.
2. Keratinocytes
The make up the majority of the cells in the epidermis. They synthesize keratin which are proteins that make up your hair, skin, and nails. They can also be found in other organs inside your body.
3. Melanocytes
These cells can only be found in the stratum basale. They synthesize melanin with a brown to black pigment. These dark pigments serves as protection for the skin from harmful UV rays.
4.Merkel cells
Merkel cells are also known as <em>tactile cells</em>. They are the sensory receptor for touch. Merkel cells and the nerve fiber together are called the Merkel disc.
5. Dentritic cells
They are also known as <em>Langerhans cells</em>. They can be found in two layers of the epidermis: the stratum spinosm; and stratum granulosm. They are what you call macrophages that come from the bone marrow. They serve as immune cells that provide protection against toxins, microbes and other pathogens that try to penetrate the skin.
Hope you find some information above that will help you.
