Answer:
plant leaves contain openings called stomata, which allow the diffusion of gas exchange
Evolution is when living things go through changes. This occurs through natural selection.
The given blank can be filled with the production of endorphins.
The endorphins are the hormones, which are responsible for the activation of the opiate receptors in the body. They are the natural pain killers. The activation of the opiate receptors causes the analgesic effects on the body.
These endorphins are secreted in the brain and the nervous system. The effect of the endorphins is similar to that of the morphine.
Answer:
Selection that acts, over evolutionary time, to enhance traits that increase an individual's ability to mate frequently or with quality partners is known as <u>sexual selection.</u>
Explanation:
Sexual selection : The process through which males and females attempt to maximise their chances of reproductive success is called sexual selection. It is a form of natural selection. Charles Darwin suggested sexual selection. Animals compete with others of the same species for the chance to mate.
<u>For example:</u> Male widow-bird grows exceptional long tail feathers, females lack tail feathers.
