ELA.6.9A Compare and contrast the stated or implied purposes (e.g., inform, influence, entertain, express) of different authors writing on the same topic. ELA.6.10A Summarize the main ideas and supporting details in text, demonstrating an understanding that a summary does not include opinions.
The shape of the breast, its size, position of nipple and their numbers are also genetically determined. Any alteration in the basic genes or the presence of a predetermined gene that governs the shape and size of the nipples can cause the nipples to be inverted.
1 Lactation also involves positive feedback in that as the baby suckles on the nipple there is a nerve response into the spinal cord and up into the hypothalamus of the brain, which then stimulates the pituitary gland to produce more prolactin to produce more milk.