The evolution of sexual reproduction is a great puzzle in modern evolutionary biology. Many groups of eukaryotic organisms, especially most animals and plants, reproduce sexually. The evolution of sex between two organisms of the same species contains two related but different themes: its origin and its maintenance. However, since hypotheses for the origin of sex are difficult to test experimentally, most of the current work has focused on the maintenance of sexual reproduction. Biologists, including W. D. Hamilton, Alexei Kondrashov, and George C. Williams, have proposed various explanations for how sexual reproduction is maintained in a large set of different living things.
        
             
        
        
        
Answer:
The answer is given below.
Explanation:
Rescorla explain this finding by stating that the tone experienced by the group of rats just before each of 20 shocks was a reliable predictor of the shock for the first group.
The psychologist Robert Rescorla stated in his famous classical conditioning experiment that  2 stimuli does not produce the same level and kind of conditioning.  Conditioning works in a better way, if the conditioned stimulus will act as a reliable signal that projects the appearance of an unconditioned stimulus. 
 
        
             
        
        
        
cause an increase in the rate of certain mutations 
 
        
             
        
        
        
Photosynthesis, the process whereby plants use light from the Sun to convert CO2 into organic compounds such as sugars, and oxygen, is one of the most important natural processes on Earth. This is a sophisticated system with a highly regulated shuttle traffic of ions and molecules that passes through several membranes. I hope I helped you and good luck and I am sorry I know it’s late at night it’s just I love to help people and I ate to much sugar
        
             
        
        
        
The hypodermis (subcutaneous tissue) is the innermost layer of skin in your body. The dermis is the middle layer. The epidermis is the outermost layer.
<h3>What does the subcutaneous layer consist of?</h3>
Subcutaneous tissue is the deepest layer of your skin. It's made up mostly of fat cells and connective tissue. The majority of your body fat is stored here. The subcutaneous layer acts as a layer of insulation to protect your internal organs and muscles from shock and changes in temperature.
<h3>What is not found in dermis?</h3>
The answer is C fat cells. So the dermis is between the epidermis and the subcutaneous tissues.
Learn more about epidermis here:
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