I am pretty sure that the layer in figure 4-1 which forms the cap rock for the oil trap is the layer F that shows an example of stratigraphic traps that includes unconformity, lens, pinch-out in which you can see how t<span>he oil is stuck inside the porosity of the rocks.
Do hope you will find it helpful! Regards.</span>
In the stomach, food undergoes chemical and mechanical digestion. Peristaltic contractions (mechanical digestion) churn the bolus, which mixes with strong digestive juices that the stomach lining cells secrete (chemical digestion). As food travels from your mouth into your digestive system, it's broken down by digestive enzymes that turn it into smaller nutrients that your body can easily absorb. This breakdown is known as chemical digestion.
It’s symmetrical if it’s equal on both sides?