Lesson 3A (Part 2) Flashcards
What are 2 types of ovarian hormones?
- Estrogens
2. Progesterone
What do ovarian hormones control?
Breast development during puberty
What does estrogen do?
Stimulates growth of the ducts of the mammary glands
What does progesterone do?
Stimulates development of the actual secreting cells
- alveoli
How is breast size determined?
More by the amount of fat around the glandular tissue than by the amount of glandular tissue itself
What is breast size not related to?
Its ability to produce milk
What cuts off a major source of estrogen in the breasts?
Shedding of the placenta after delivery of the baby
What does the rapid drop in the blood concentration of estrogens do?
Stimulates the anterior pituitary secretion of prolactin
What stimulates the anterior pituitary secretion of prolactin and the posterior pituitary secretion of oxytocin?
Suckling movements of a nursing baby
What does prolactin simulate?
Lactation
- stimulates alveoli of the mammary glands to secrete milk
When does milk secretion start?
About the third or fourth day after delivery of a baby
Colostrum
The first secretion of the mammary glands after giving birth
- this yellowish secretion
What is colostrum rich with?
Antibodies
What does oxytocin stimulate?
Myoepithelial cells in the alveoli of the breasts
What does oxytocin do?
Stimulates the myoepithelial cells in the alveoli of the breasts to eject milk into the ducts
What is the arterial blood supply for the breast? (2)
- Thoracic branches of the axillary arteries
2. Internal mammary and intercostal arteries
What is the venous drainage of the breast? (3)
- Anastomotic circle round the base of the nipple
- Branches carries the venous blood to the circumference
- End in the axillary and mammary veins
What is the lymph drainage of the breast? (3)
- Superficial axillary lymph vessels and nodes
- Lymph may drain through the internal mammary
- Nodes if the superficial route is obstructed
Anastomotic circle
Cycle around the area of the nipples and it carries out branches
What is a common way malignant breast tumours spread?
Through the lymphatics
What branches of the thoracic nerves contain sympathetic fibres? (3)
- 4th
- 5th
- 6th
What is numerous in the breast, especially around the nipple?
Somatic sensory nerve endings
What are somatic sensory nerve endings stimulated by? (3)
- Sucking
- Impulses pass to the hypothalamus
- The flow of the hormone oxytocin is increased
- promoting the release of milk
What is a normal process that occurs in women as they age from about 25 to 45 years old?
Involutional breast change
