Answer: food chains or webs
In an ecosystem, energy from the sun is transferred by the way of food chains or webs. A food chain is a linear sequence of organisms through which food and energy is passed as one organism eats the another. A food web is the interconnection or relation of food chains. In a food chain energy is distributed among the trophic levels. Plants are primary producers which traps energy from sun for photosynthesis and belong to first trophic level in the food chain. The energy of sun present in plants is transferred to subsequent higher trophic levels when plants are consumed by other organisms. 
 
        
                    
             
        
        
        
A person can be anxious when making an important decision when faced with a problem at work. Types of disorders are;
1. Generalized anxiety disorder symptoms include
a) irritability
b) muscle tension
c)Being easily fatigued.
2. Panic disorder symptoms include
a)feeling of being out of control during a panic attack.
b)Repeated and sudden attack of intense fear.
3. Social anxiety symptoms
a)Having a very hard time making friends.
b)feelings of self-conscious in front of other people
c)Staying away from where other people are.