Term
1. What is the hormone that changes the reproductive tract during the late follicular stage?
2. What are the changes? |
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Definition
1. Estrogen
2. Cervical epithelial cells create more watery secretions. pH of mucous in increased. Contractions of the myometrium and smooth muscle around the oviducts propel the sperm toward the ampulla. |
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Term
| What receptors are triggered by estrogen in the ampulla that result in contractions that aid in the movement of sperm? |
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Definition
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Term
| When is the second polar body extruded from the ovum? |
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Definition
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Term
| What allows the movement of the embryo into the uterus? |
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Definition
| As progesterone levels increase due to the evolving corpus luteum, smooth muscles around the oviduct express increasing amounts of beta adrenergic receptors that allows relaxation. |
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Term
| How large is the embryo once it enters into the uterus? |
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Definition
| It is a blastocyst of 100 cells. |
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Term
| How long after ovulation does implantation occur? |
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Definition
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Term
| What hormonal conditions are necessary for implantation to occur? |
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Definition
| The progesterone/estrogen ratio must be high. This occurs during maximal corpus luteum activity. |
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Term
| What does the outer rim of the blastocyst develop into? What are their function? |
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Definition
| Trophoblasts. Which attach the blastocyst to the uterine wall. |
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Term
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Definition
| These are cells of the endometrium that differentiate due to continued exposure to progesterone. |
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Term
| What are syncytial trophoblasts? |
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Definition
| These are differentiated tropoblasts thare destroy the adjagent decidual cells via phagocytosis allowing the blastocyst to penetrate the endometrial wall. These also become the major hormone producers, taking the role of the corpus luteum. |
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Term
| What is the role of the progesterone produced by the syncytial trophoblasts? |
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Definition
1. Maintains the uterine wall
2. Keeps the myometrium active
3. Supports the production of cervical mucus that seals off the uterine cavity. |
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Term
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Definition
| It sheds the lining of the uterine cavity preventing implantation. |
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Term
| What is the role of the placenta? |
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Definition
| It is a vascular organ for exchange of gases and materials. It also produces a large number of steroids: estrogen, hCG, GH, TSH, ACTH. After 7 weeks sufficient progesterone is synthesized by the placenta to maintain pregnancy without the effects of the pituitary or corpus luteum. |
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Term
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Definition
| Maintains the corpus luteum, which maintains progesterone and estrogen production, and supresses the release of pititary gonadotropins, preventing the recruitment of new follicles. |
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Term
| When does the corpus luteum involute and become non-fucntional during pregnancy? |
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Definition
| After the 1st trimester, when placental progesterone predominates. |
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Term
1. What hormone is synthesized in greatest amount in both man and woman?
2. What is the function of it? |
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Definition
1. Human Chorionic Somatamammotropin (hCS)
2. Function is unknown |
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Term
| What is the source of cholesterol in placental hormones? |
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Definition
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Term
| What does estrogen synthesis from the placenta require? |
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Definition
| Androgen substrates from maternal and fetal adrenals due to the lack of 17alpha-hydroylase. |
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Term
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Definition
| Placental estrogen that is created from DHEA-S |
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Term
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Definition
| Neurohormone that is secreted from the posterior pituitary that produces powerful contractions of the myometrium late in pregnancy. |
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Term
| T/F: Oxytocin is the trigger for parturition. |
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Definition
| False. Oxytocin levels do not increase until AFTER the initiation of parturition. It is secreted in response to uterine stretching. |
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Term
| What are the mammary gland secretory structures and what do they converge to form? |
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Definition
| Lobuloalveolar Ducts. They converge to form Lactiferous Ducts, which carry milk to the nipple. |
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Term
| What stimulates the growth and branching of the mammary glands? |
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Definition
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Term
| What is necessary for lactation to continue in a nursing woman? |
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Definition
| Frequent emptying of the ducts will allow lactation to continue. |
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Term
| What prevents lactation during pregnancy? |
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Definition
| High levels of estrogen and progesterone combine to prevent prolactin stimulation of casein synthesis. At parturition, both estrogen and progesterone levels fall allowing casein synthesis to occur. |
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Term
| What is the milk let down reflex? |
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Definition
| Suckling triggers a neuroendocrine reflex that allows milk to be secreted easily from the nipple. Oxytocin stimulates the myoeithelial cells around the alveoli to contract. |
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Term
| What is the role of Prolactin? |
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Definition
| Acts on the alveolar epithelium inducing the transcription of casein genes. |
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Term
| What type of birth control can lactating women use? |
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Definition
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