try A or b, they both have a membrane i belive
The menstrual cycle is practically controlled by a system of hormones that is necessary for reproduction, and when the hormone reaches a heightened level, something called estradiol is made, then the stimulation of the ovaries by a luteinizing hormone.
Once that hormone begins developing, the ovaries make an egg that quickly becomes an ovum. The ovary then releases one egg or two during ovulation. The endometrium (the part that sheds its own cells for the menstruation) peaks after ovulation and changes the lining of the uterus to prepare for the hectic process of pregnancy and child labor.
Hope that was helpful.
Hello Littlefoot2645. I do believe the answer would be that of the process of "mutation," thus it occurs by human interference, specifically, although, initially, naturally-speaking, only occurring by natural selection in onslaught of period time frames.
Answer:
B
Explanation:
The whole point of natural selection is for animals to compete to survive in that specific environment
Hope this helps!
Answer:
You did not write the concept, so i will try to answer in a general way.
Why sometimes we really need to model concepts?
Well, sometimes the things are really complicated, or we just do not have the knowledge or tools to fully understand them.
Here is where the models came to be handy, we can somewhat "simplify" the things, and explain them with models.
For example, the movement of a particle as the wind pushes it can be really complex, so this can only be explained with a model.
Now, once we have a model (supported by theory and experiments) we can start to investigating furthermore in the given subject.
So for example, we could model how a given therapy acts on a given disease, and with that model, we could extrapolate the effects of the therapy in a similar disease (for example, testing how radiotherapy acts on a given tumor in some organ, can give information on how the same therapy can act on other types of tumors)
Concluding, models simplify some concepts, which allow us to understand them and work better with them
