BIOLOGY!

Tomorrow's paper gonna be FQAH0113, or in simpler understandable language, Biology 3 which consists of photosynthesis, digestive system, homeostasis, nervous system, circulatory system and lymphatic system. Or does lymphatic system categorize under circulatory system? Maybe. Nahh they won't ask about that.

So here is my summary of what I've read. So.....here goes nothing!

Autotrophic nutrition is divided into two, photoautotroph and chemoautotroph. They differ in their sources of energy and sources of electron. And then there are phosphorylation, cyclic and non-cyclic. The non-cyclic phosphorylation produces ATP and NADH and O2 as waste, while cyclic produces on ATP since it occurs due to lack of NADP+. And then we got the Calvin cycle. And then there are C4 and CAM plant. C4 plant cycle occurs in two distinct cells, while CAM plant which first discovered in Crassulaceae family occurs in two different times. And voila.

And then regarding digestive system. They spotted that only digestion in stomach will comes out, and well, I read about it only. Not sure if it's a good thing though. So yeah, structure of stomach. It is divided into three region, pyloric, cardiac and fundus. And the wall of stomach has four layers ; inner mucosa, mucosa, muscle layer and serosa. Well, there are three layers of muscle layer which is the outer (longitudinal). middle (circular) and inner (oblique). The mucosal layer is thick and has many epithelial cells which fold inward, forming gastric pits. These pits form gastric gland, which contains zymogen cell (secrete pepsin and rennin), oxyntic cell (secretes HCl) and goblet cell (secrete mucus). Contraction of pyloric and cardiac sphincter ensure that the food that hasn't been fully digested to not exit the stomach into duodenum. The mixture of all food that are digested becomes semi-liquid which are called chyme. And that is all about it I think.

And then there are homeostasis. Blood glucose level regulation. Well when blood glucose increase, the beta cell of islets of Langerhans in pancreas (pancreas acts as endocrine gland) secrete insulin. Insulin will convert glucose into three things ; CO2+H2O, glycogen, fats. And the blood glucose level will decrease, and back to normal which is usually 90mg/100ml. Meanwhile, if the blood glucose level decrease or falls from normal, alpha cell of islets of Langerhans will secrete glucagon which will convert glycogen into glucose and reduce glucose oxidation. This will bring the blood glucose level back to normal. More information, if there is failure in secreting insulin blood sugar level will rise and this would be called hyperglycemia. There would be excess of glucose in urea which is called glycosurea. Now this person is known to have diabetes mellitus. Conversely, if blood glucose level falls below normal, it is called hypoglycemia. There are two types of diabetes. The first one is when there are antibodies which mark the beta cells for destruction causing no secretion of insulin wile the second type of diabetes is when insulin receptor on target cell does not bind. 

Nervous system. I've read about synapse, impulse transmission, drug mechanism, sliding filament theory, knee jerk, receptors in eye and ear and about steroid and non-steroid hormones. To be writing about all of these would take another hour, so I'm just gonna pass.

Well, last but NOT least obviously, circulatory system. Ahh too sleepy. Just a little more. I'd like to write about human heart cycle. First, the heart is in diastole phase, which means it's relaxed. Then oxygenated blood from lung will come in through pulmonary vein into left atrium and deoxygenated blood through vena cava into right atrium. 80% of the blood will directly enter ventricles and heart will begin to contract. Atrium will first contract, finishing the remainders of 20% blood into ventricles. Heart is now in systole phase by the way. AV valves would be the ones to prevent the blood from entering atrium again. And now the ventricle will start contracting, stronger than atrium. The blood will now be pushed out of ventricle with semilunar valves helping preventing the blood from flowing back in. Some blood goes out through aorta to all body parts while some will goes to the lungs, through pulmonary artery. Oh lymphatic system, I haven't read about it much yet.

And ohh, immunity response. Too many to write about. Just to mention that there are three lines of defense in our body, and the third one consists of specific immunity response which consists of another two ; cell mediated and humoral.

Have literally used up all energies. Good night. Good morning. Bye! And do pray for us thank you <3