Controls In The Human Body Flashcards
What is a hormone?
a regulatory substance produced in an organism transported in blood to stimulate specific cells or tissues into action.
How do hormones travel around the body?
Hormones travel throughout the body, either in the blood stream or in the fluid around cells, looking for target cells. Once hormones find a target cell, they bind with specific protein receptors inside or on the surface of the cell and specifically change the cell’s activities.
What is a gland?
an organ in the human body which secretes particular chemical substances for use in the body or for discharge into the surroundings.
What is the menstrual cycle?
the process of ovulation and menstruation in women
How long does the menstrual cycle last?
3-10 days
What is the role of FSH? Where is it produced?
The hormone FSH is secreted by the pituitary gland. FSH makes two things happen:
-it causes an egg to mature in an ovary
-it stimulates the ovaries to release the hormone oestrogen
The hormone oestrogen is secreted by the ovaries. Oestrogen makes two things happen:
-it stops FSH being produced - so that only one egg matures in a cycle
-it stimulates the pituitary gland to release the hormone LH
What is the role of LH? Where is it produced?
The hormone LH causes the mature egg to be released from the ovary.
Progesterone is a hormone secreted by ovaries. It maintains the lining of the uterus during the middle part of the menstrual cycle and during pregnancy.
If an egg is not fertilised, what happens?
It is realised at some point in the menstrual cycle
How do contraceptives use hormones to control fertility?
Contraceptives such as the oral contraceptive, ‘the pill’, greatly reduces the chances of mature eggs being produced. The pill contains oestrogen, or oestrogen and progesterone. These hormones inhibit the production of FSH, which in turn stops eggs maturing in the ovaries.
What happens during vitro fertilisation (IVF)?
During IVF, an egg is removed from the woman’s ovaries and fertilised with sperm in a laboratory. The fertilised egg, called an embryo, is then returned to the woman’s womb to grow and develop.
What is a hormone?
a regulatory substance produced in an organism transported in blood to stimulate specific cells or tissues into action.
How do hormones travel around the body?
Hormones travel throughout the body, either in the blood stream or in the fluid around cells, looking for target cells. Once hormones find a target cell, they bind with specific protein receptors inside or on the surface of the cell and specifically change the cell’s activities.
What is a gland?
an organ in the human body which secretes particular chemical substances for use in the body or for discharge into the surroundings.
What is the menstrual cycle?
the process of ovulation and menstruation in women
How long does the menstrual cycle last?
3-10 days
