<h3>I think it's helpful for you ✌️✌️✌️✌️✌️✌️❤️</h3>
<u>Answer:</u>
Recent evidence suggest that feathers evolved from scales and suggest that 'feathers and pycnofibers' could be homologous.
<u>Explanation:</u>
- One of the major difficult issue related to bird evolution is the evolution of feathers.
- Feathers are considered as the most 'complex integumentary structures' which are found in vertebrates.
- Evolutionary developmental biology suggests that the 'planar scale structure' is been modified for developing into feathers by 'splitting' to form web like structures.
- Scales and Feathers consist of 'two distinct form of keratin' so it was thought that 'each type was exclusive skin structure' but recent study suggests that they are developmental expressions of same skin structures.
Answer:
Explanition:
The immune system is made up of special organs, cells and chemicals that fight infection (microbes). The main parts of the immune system are: white blood cells, antibodies, the complement system, the lymphatic system, the spleen, the thymus, and the bone marrow.
<span>Cells primarily recognize exposed hydrophobic patches when identifying misfolded proteins. This is very prevalent in bacteria and I would assume that similar mechanisms are used in eukaryotes. There is also a system where misfolded proteins are tagged by different glycosylation patterns, but I don't remember much about that part.</span>
