6.5b: Homeostasis – Glucose Regulation

24/10/2013 § Leave a comment

Hi, hello, I wrote about glucose and diabetes in the previous blog so if the idea of liver breaking down glycogen into glucose appeals to you, click away!



Page 261, the glucose tolerance test

a) The concentration of glucose at time zero, i.e. before the consumption of the glucose drink. The diabetic individual already has a higher concentration of glucose (~160 mg 100 cm-3) than the unaffected individual (~76-78 mg 100 cm-3).

b) The length of time required to return to the level at time zero. The unaffected individual takes roughly 3 hours to return to the level at time zero, but the diabetic needs more than 5 hours.

c) The maximum glucose level reached. The diabetic reaches 350+ mg 100 cm-3 of glucose concentration while the unaffected individual only reaches around 150-155 mg 100 cm-3 of glucose.

d) The time before glucose levels start to fall. The unaffected individual’s glucose levels start to decrease after 1 hour, but the diabetic’s glucose levels fall after 2 hours.

6.5a: Homeostasis – Thermoregulation

22/10/2013 § 1 Comment

There’s an environment in every single one of us (ooh, so deep) and they are maintained through a control process called homeostasis, which is maintaining the internal environment of the body between limits. By limits, I think they mean the high and low points. Homeostasis controls body temperature, blood pH, carbon dioxide concentration, blood glucose concentration, and water balance. The nervous and endocrine system are responsible for sending messages to various glands in our bodies to release hormones that help maintain equilibrium in our bodies.

Okay, so negative feedback is a huge part of this topic. When some part of your internal environment is going haywire, or some levels are too high or too low, the body emits negative feedback in order to bring your body back to acceptable levels.

« Read the rest of this entry »

6.4: The Respiratory System

21/10/2013 § Leave a comment

I hope everyone will forgive me for not writing a general summary about the reading this time, it’s been a busy – wait, I’m not going to apologise to the Internet, hahahAHAHAHA.

What am I doing with my life.

« Read the rest of this entry »

6.2b: The Transport System

17/10/2013 § 1 Comment

Apparently blood is a tissue, not just a liquid. In fact, blood is a liquid tissue; isn’t that so strange. What we think of as blood is actually a combination of different kinds of blood cells and a fluid called plasma that holds a great many things including waste products and dissolved nutrients. The role of blood is to transport these materials throughout the body, but also to bring heat from warmer parts to colder parts of the body.

Blood also consists of two main kinds of cells: we know of them as red blood cells and white blood cells. Red blood cells, here appropriately titled erythrocytes, hold haemoglobin and are in charge of increasing the blood’s oxygen-carrying capacity. White blood cells, here they are called leucocytes, are our little fighters and they mainly fight off disease. There are two kinds of leucocytes for this unit and they are: phagocytes, which take care of foreign material that enter our body, and lymphocytes, which produce antibodies that our system needs.

« Read the rest of this entry »

6.2a: The Transport System

15/10/2013 § 1 Comment

Hahahahaha, okay, I’m glad we’re out of the digestive system because that stuff makes me feel queasy. The heart is so much more welcoming. You could say this topic is more… heartwarming.

Oh my god that doesn’t even work.

Anyway, the heart. The heart is composed of cardiac muscle (hence we call the heart and vein system the cardiovascular system) and is a double pump. The right side pumps blood to the lungs and is called the pulmonary circulation. The left side pumps blood to all of the other organs in the body and is called the systemic circulation. In the pulmonary circulation, blood that flows through is deoxygenated. Once it gets to the heart for systemic circulation, it’s been oxygenated. These two flows of blood shouldn’t mix.

The pumping of the heart is super systematic. Structures called the atria (atrium = singular), are the collecting chambers in the heart and are responsible for gathering blood from the veins. Then there are ventricles, which are the main pumpers, using high pressure. Then there are valves that are there to make sure blood always flows the right way and never back or into the wrong tube (vein/artery).

« Read the rest of this entry »

6.a: The Digestive System

10/10/2013 § Leave a comment

Hahahahaha 7 pages, no.

Judge me all you want, but no.

« Read the rest of this entry »

D.4: Hardy-Weinberg Equilibrium

01/10/2013 § Leave a comment

Wha – wait, what, we’re going to do math in biology as if science wasn’t enough, you expect me to be able to add math into the mix, are you crazy, syllabus?!

Oh, it’s only quadratics.

The Hardy-Weinberg principle involves (relatively simple) math in order to calculate certain frequencies, including phenotype frequencies, allele frequencies, and genotype frequencies. Alleles are normally represented by variables p and q. The total frequency of alleles in a population is 1.0, therefore p + q = 1. The information anyone will need to do these calculations are the allele frequencies and genotype frequencies.

The Hardy-Weinberg equation can only be done if the population fits into a few assumptions:

  • random mating happens in the population
  • natural selection doesn’t cause higher mortality of individuals with one allele than another
  • no mutation
  • population isn’t too small
  • no immigration or emigration

« Read the rest of this entry »

Where Am I?

You are currently viewing the archives for October, 2013 at i am so.