Answer:You may feel hungry frequently if your diet lacks protein, fiber, or fat, all of which promote fullness and reduce appetite. Extreme hunger is also a sign of inadequate sleep and chronic stress. Additionally, certain medications and illnesses are known to cause frequent hunger.
Explanation:
"Hunger hormones" (ghrelin) in your blood and an empty stomach signal the brain when you're hungry. Nerves in the stomach send signals to the brain that you're full, but these signals can take up to 20 minutes to communicate -- and by that time, you may have already eaten too much.
 
        
             
        
        
        
Vascular systems are important to transport materials throughout the organism.
        
             
        
        
        
Answer:
No
Explanation:
Animals can not perform photosynthesis. Plants are the only things that can perform photosynthesis. They have special cells designed to perform the process. No human or animals can perform photosynthesis. They have to find food on their own.
 
        
                    
             
        
        
        
Answer: Phagocyte receptors that detect PAMPs
Explanation:
TLRs or Toll-like receptors, are a family of proteins that are part of the innate immune system. TLRs are transmembranous and recognize pathogen-associated molecular patterns (PAMPs), which are groups of chemical characteristics common to certain types of pathogens. Patterns detected by TLRs include lipopolysaccharide, a compound found on the surfaces of Gram-negative bacteria, and double-stranded RNA, which is an integral part of the life cycles of many viruses. These PAMPs are generally important for the survival of the pathogen, so they are well preserved. <u>Activation of these receptors induces inflammatory responses in leukocytes of myeloid lineage, signaling via NF-κB, which is a transcription factor that activates pro-inflammatory genes</u>. Activated TLRs also increase the production of co-stimulatory molecules such as CD80, CD86 and CD40. These proteins, expressed on the surface of antigen-presenting cells, are necessary for the activation of T-lymphocytes by dentritic cells and macrophages already showing antigens in their MHC type II molecules (Major Histocompatibility Complex, they participate in the presentation of antigens to T lymphocytes)
<u>In addition, TLR-mediated signaling on antigen-presenting cells (APCs) plays an important role in linking the innate and adaptive immune responses</u>.