We need the multiple choices for this question.
Answer: B
Explanation: A closed system can be defined as a system that does not allow for an exchange of matter with its surroundings.
An estuary where fresh water and ocean water mix is not a good example of a closed system because fresh water and ocean water mix out in the open and matter is exchanged.
A living single-called organism such as phytoplankton does not constitute as a closed system because in order for the phytoplankton to be considered alive it needs to interact with its surroundings i.e light from the sun so photosynthesis (converting light energy into chemical energy to be used by organism) can occur. This also happens out in the open
A river that flows into the ocean does not fit into the closed system definition. This is because a river that flows into the ocean allows for itself (matter) to mix with that of the ocean in an open space (rivermouth).
Therefore option B is the answer because it fits the definition. A chemical reaction within the deep ocean organisms that allows them to glow happens within (inside) the organism, making this system closed, hence there is no exchange of matter with surroundings.
<u>Definition:</u>
The sex hormone and endogenous steroid present in human and other species ' menstrual cycle, pregnancy, and embryogenesis are known as "Progesterone" while the primary sex hormone in females responsible for the development and control of the female reproductive system and for the characteristics of secondary sex is termed as "Estrogen" or "oestrogen".
<u>Progesterone Effects:</u>
- Progesterone has a variety of physiological effects which are exacerbated when estrogens are present for an instance in breast tissue, where estrogens permits progesterone to mediate lobuloalveolar development.
- Progesterone has main effects on human sperm by non-genomic signals, as they move through the female tract before fertilization.
- Progesterone is called "hormone of pregnancy" as transform the endometrium to its secretory stage for uterine implantation, decrease the maternal immune response to permit for the acceptance of the pregnancy during implantation and gestation, prevent preterm labor, inhibits lactation during pregnancy etc.
<u>Estrogen Effects:</u>
- Effects structure of human and categorize them as male and female, while females have three kind of estrogen: Estrone (weak and found in women after menopause), Estradiol (strong and it is steroid produced by ovaries ) and Estriol (weakest and waste product after body produces estradiol).
- It effects ovaries, vagina, Fallopian tube, uterus, cervix and mammary glands.
- It triggers the release of an egg due to high level during halfway of cycle but decreases after ovulation.
<u>Similarities between progesterone and estrogen: </u>
Progesterone and estrogen as such do not have similar function but work with coordination as both are need for menstrual cycle functioning and regulation. Estrogens usually travel in fluids through the bloodstream, communicate with cells in the body's various tissues, and provide a message or guidance while progesterone helps to balance pregnancy period and to implant an egg in uterus.
Answer: Can you be more specific please?
Explanation: