To be frank starch is made up of long chains of glucose. While cell walls are made from cellulose created from photosynthesis. Cellulose is made up of glucose and cell walls are the most abundant carbohydrate.
Answer - Ground water erosion is a type of carbonic acidic water. That goes into the holes thru the soil and pretty much cracks thru rocks.
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.