Biology Revision for "O" level examinations

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Hello everyone. I know that there are thousands of you out there who are anxiously waiting your cxc grades. I really hope that your Grades are as you expect. However, it is not the end of the world if you did not achieve what you expected. There is always going to be another opportunity for you to excel. Never give up. Below is the link that you can use to log in to check your CSEC Grades. According to CXC the grades should be available from tonight at 22:00 hours (Today is 16th August). However, it is possible that students in Guyana might have some issue because the government may block it from students who did not submit their text book. We have to wait and see. Click on the link below to access the student portal CXC Student Portal: Student Results Best wishes everyone!

Red Blood cells/erythrocytes -they are formed in red bone marrows of the ribs, skull and vertebrae -survive for approximately 120 days and are then destroyed in the liver and spleen Structure and Function -contains no nucleus: this allows more room for haemoglobin (also: cells cannot divide/reproduce ) -they have biconcave disc shape to increase surface area -contains hemoglobin that allows the transport of oxygen White Blood cells/Leucocytes a. Phagocytes Function: They engulf and digest invading bacteria and viruses.   Structure:             -their shape may vary             -they move using pseudopodia             -its nucleus is lobed shape             -they are formed in...

Hypertension •          B lood flows through the blood vessels with a force greater than normal i.e. with a blood pressure reading of 140/90 •          When the blood pushes harder against the walls of your arteries, your blood pressure goes up Prevention •          Quit smoking •          Exercise regularly •          Reduce amount of sodium •          Eating a healthy diet Coronary Heart Disease/ Heart  attack •          A heart attack happens when the flow of oxygen-rich blood to a section of heart muscle suddenly becomes blocked and the heart can’t get oxygen. •          If blood flow isn’t restored quickly, the...

Hello everyone. Most of the contents be be posted on my new website. I will also be placing past examinations papers on my new website. Link : http://www.biologynotes101.com/index.html