5. Name the two types of twins and describe how they are formed.

There are two types of twins – identical (monozygotic) and fraternal (dizygotic). To form identical twins, one fertilized egg (ovum) splits and develops two babies with exactly the same genetic information. Twins are more or less equally likely to be female or male.

Explanation:

Identical/Monozgonic-one fertilised egg (ovum) splits and develops into two babies with exactly the same genetic information.

Fraturnal/Dizygotic-two eggs (ova) are fertilised by two sperm and produce two genetically unique children.

since you have not provided the options here i   am going to give you general overview about hormone.hormone are actually the part of endocrine system in our body and produced by the endocrine glands. the hormones act like a chemical messenger   within human body. once produce by the glands they   travel through the blood stream and reach at specific or target tissue and organs   which result in control of our body function. the hormones are specific in their work and work on only the targeted tissue or organ   . with the of hormone endocrine system regulate the heart rate , metabolism, our mood and   growth as well as the development and even the sleeping cycle etc. they actually are the messenger for body cell and organs .