What are the most important events that occur in the uterine cycle?
What will be an ideal response?
The uterine cycle averages 28 days in length and has three phases: the menses, the proliferative phase, and the secretory phase. The cycle begins with the onset of menses on day 1, continuing usually until day 5. At this time the functional zone of the endometrium is shed, in a process called menstruation. This process was triggered when the estrogen and progesterone levels fell at the end of the previous cycle. After the menses, under the influence of the circulating hormones, the epithelial cells of the endometrium multiply and spread across the surface. This will restore the functional zone, and coincides with the maturation of the egg prior to ovulation. When ovulation occurs, the functional zone is several millimeters thick and ready to receive the fertilized ovum. The secretory phase allows
the endometrial glands to enlarge under the effects of the progestins and estrogens secreted by the corpus luteum. It continues until approximately 12 days after ovulation. Glandular activity then declines as the corpus luteum deteriorates, and the functional zone is eventually shed at the start of a new cycle.
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Infancy:
a. begins at birth b. ends at about 18 months c. includes the neonatal period d. all of the above
Which component of the diencephalon is stimulated by changes in body temperature?
A) choroid plexus of the epithalamus B) pineal gland C) ventral nuclei of the thalamus D) preoptic area of the hypothalamus E) paraventricular nucleus of the hypothalamus
Proteins are composed of subunits called ________ and functional proteins include ________, which speed up chemical reactions in the body.
A. fatty acids; triglycerides B. amino acids; enzymes C. amino acids; antibodies D. fatty acids; enzymes
When dehydration synthesis occurs between two amino acids, a covalent bond called a _________ bond forms between them.
Fill in the blank with correct word.