Ions are atoms which have a missing electron or an extra one. This is what gives the ion its positive or negative electrical charge. Isotopes are atoms which contain a different number of neutrons.
Answer:
A. Menstruation and the estrogen surge
Explanation:
The events that occur simultaneously in the monthly female reproductive cycle are menstruation and estrogen increase.
The menstrual cycle lasts about 28 days and is controlled by the secretion of gonadotropins (FSH and LH), secreted by the pituitary, and estrogen and progesterone, produced by the ovaries. The first day of the cycle corresponds to the first day of menstruation. During menstruation, levels of sex hormones in the blood are low. By the sixth day, the pituitary again secretes a greater amount of follicle stimulating hormone (FSH).
Therefore, in this first phase of menstruation, the pituitary secretes the hormone FSH, which, as the name implies, will stimulate the development of ovarian follicles. In turn, the follicles produce estrogen, which stimulates the growth of cells in the uterine inner wall, the endometrium, which becomes thicker and well-vascularized. These are changes that prepare the uterus for the implantation of an embryo, ie a pregnancy.
The high concentration of estrogen in the blood stimulates the secretion of luteinizing hormone (LH). LH induces ovulation, which occurs around the 14th day of the cycle. Next, the LH induces the rupture of the ovarian follicle and the consequent release of the egg, besides leading to the development of the corpus luteum. The corpus luteum produces progesterone, which will assist in maintaining the endometrium until the end of the menstrual cycle.
Answer:
B. Plasmid incompatibility will not allow both plasmids to persist
Explanation:
The two possibilities of why the plasmids are incompatible are:
1) Both plasmids contain the same origin of replicon and compete for the same Rep proteins.
2) Tetracycline: inhibits protein synthesis by binding and inhibiting ribosomal proteins, thus ampicillin target proteins may also be inhibited.
Ampicillin: Causes cell lysis which may lead to inactivation of tetracycline activity since tetracycline needs to diffuse through membrane porin channels prior binding and inhibiting ribosomal proteins.
Excreting urea helps in maintaining internal homeostasis by retaining water.
The mammals like humans excrete urea, while reptiles and birds, and some terrestrial invertebrates generate uric acid as waste. Generating uric acid in place of urea is beneficial as it is less toxic and diminishes water loss and the subsequent requirement for water.
This retention of water helps birds and reptiles to sustain internal homeostasis mainly in hot weather.
Answer:
The weight of the plants at the end of the experiment.
Explanation:
Since the experiment was set up to study the growth of the wheat plants, weight is a sign of growth. So at the end of the experiment, the weight of the plant will be compared to the amount of nitrogen added.
If a graph is to be plotted, the amount of nitrogen (independent variable) will be on the x-axis and the weight of the plants (dependent variable) will be on the y-axis.
The amount of sunlight and temperature are not included because the question does not say that they are parameters in the experiment.