What are the organ's main functions ?

In an organ, different tissues work together to carry out a particular function. These are the main organs, as well as their primary function:

The brain controls thoughts, memory and other organs.

The heart pumps blood around the body.

The lungs separate oxygen from the air and remove carbon dioxide from the blood.

The stomach helps to digest food.

The intestines absorb nutrients from food.

The liver removes poisons from the blood.

The kidneys filter blood and produce urine.

The bladder stores urine.

The skin protects and contains the other organs.

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.