how can we say genes control characteristics or traits?
Answers
Answer:
Usually Genes which are segment of DNA are responsible for certain characteristics and traits in a person. Gene's are interlinked with hormones which emits the change. For example in male Testosterone is responsible for male behavior and characteristics like hairs on face,deep pitch voice,sperm production,etc same way in females hormones progesterone and estrogen are responsible for menstrual cycle,female characteristics,ovulate formation,etc
Answer:
Chromosomes contain the recipe for making a living thing. They are found in almost every cell’s nucleus and are made from strands of DNA (deoxyribonucleic acid). Segments of DNA called "genes" are the ingredients. Each gene adds a specific protein to the recipe. Proteins build, regulate and maintain your body. For instance, they build bones, enable muscles to move, control digestion, and keep your heart beating.
Most of our cells contain 46 chromosomes (here is an early look at our chromosomes, taken in the 1950s by Dr. Joe Hin Tjio of the National Institute of Diabetes and Digestive and Kidney Diseases). Sperm and egg cells contain only 23 chromosomes. When the sperm and egg cells unite, the resulting fetus inherits half of its DNA recipe from its mother and half from its father.
Two of these 46 chromosomes determine the sex of a person. A girl inherits two X-chromosomes, one from her mother and one from her father. A boy inherits one X-chromosome from his mother and a small Y-chromosome from his father.