Data Link Layer
transport layer
The Transport layer is responsible for taking a message that is too long and breaking it into smaller segments to send out. The reverse is also true, when the information is received the Transport layer is responsible for taking a series of short segments and putting them together again. Hope this helps.
The Transport layer
data link
Segments
The ozone layer is breaking due to CFC's. They are man created ODS.
papillary layer is responsible for fingerprints
segments
The skin comes in three layers, your epidermis is your outermost layer, your dermis is your middle layer and your last layer is called the fatty layer, because it is the thickest layer!
Transport layer
Datagrams TCP/IP layer 4 PDU's are called segments...
Physical layer devices would be a hub or a repeater to connect multiple Ethernet segments together.