Answer:
the answer is 50 percent 
Explanation:
please give brainliest!!!
 
        
                    
             
        
        
        
Answer:
Hypothalamic-pituitary-adrenal axis (HPA axis)
Explanation:
- The three-stage process describing the physiological changes that take place in the body when it is under stress is known as general adaptation syndrome (GAS).
 - The model describing the three-stage process was given by the scientist Hans Selye.
 - According to this model, the responses in the body that occur during stress is regulated by the Hypothalamic-pituitary-adrenal axis (HPA axis) where the brain senses the stress and then the signals travel from the hypothalamus to the pituitary and finally the body releases cortisol from adrenal glands that contributes to the various changes. 
 
 
        
             
        
        
        
Answer:
Part of the extracellular matrix secreted by osteocytes. (Ans. B)
Explanation:
Cells which are present on bones are known as osteocytes. Bone is composed of extracellular matrix, and cells. There are three types of cells which are present in the bones:
1) Osteoprogenitor cells.
2) Osteoblast.
3) Osteocyte.
Extracellular matrix is composed of organic matrix consisting glycoproteins, proteoglycans, osteocalcin also known as calcium binding proteins, and osteonectin which anchors bone mineral to collagen.
 
        
             
        
        
        
I believe the answer is Unicellular Euglena. 
Euglena are unicellular organisms classified into the kingdom protista, and the phylum euglenophyta. All euglena have chloroplast and can make their own food by photosynthesis. They are considered to have both plant and animal features. The mobility of Euglena also allows for hunting capability, because of this adaptation. 
        
             
        
        
        
Explanation:
Many invertebrate animals cant survive in water that has been polluted and resulted in a lowering of oxygen concentration so the presence or absence indicates the extent to which a body of water is polluted.
Lichens can be used to indicate air pollution as they grow exposed to places such us rocks and tree barks. They need to be efficient at absorbing water and nutrients to grow there. Rain water contains enough nutrients to keep them alive. Air pollutants dissolve in rain water especially sulfur dioxide can damage lichens and prevent them from growing. This makes them a natural indicator of air pollution.