IGCSE Biology － Free Online Lesson and Q&A Session

8 responses

1. I did not UNderstand the blood and circulation and the passage of blood through blood vessels Please give a good response to adress this matter

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   1. Hello Caleb,

      Thank you for your question!

      Here’s a short explanation of how the blood circulation works:

      Blood carries oxygen and nutrients to cells and removes waste. It flows through arteries, veins, and capillaries. The heart pumps blood throughout the body, with arteries carrying oxygen-rich blood away and veins bringing oxygen-poor blood back.

      Would you like a more detailed explanation? Please wait for our next free IGCSE Biology lesson. You can sign up for our newsletter here: https://skolatis.com/newsletter/ to be notified about the schedule.

      We hope this helps!

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2. Thank you!

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   1. Hi Hanah,

      You are most welcome.

      If you have any questions for our subject matter experts, please ask them here in the comment section.

      Thanks, and we hope to see you more here.

      Reply

3. Dear IGCSE team,
   I faced a problem in this question (0610/m/j/42/19 question 2 part b)…regarding limiting factors
   I could compare but what should I write for explaining ,in the answer?
   Thanks
   Nawal.

   Reply

   1. Hi Nawalamir,

      Are you referring to the 0610_s19_qp_42 paper? Upon checking your question we noticed it does not relate to limiting factors but rather about an experiment on carbon dioxide concentration. To help you with your problem, could you kindly help us to clearly understand which question paper you need assistance with?

      Thank you for using IGCSE Centre to sharpen your skills and we look forward to your response.

      Best Regards,
      Biology Department

      Reply

      1. I’m sorry for the inconvenience caused. I will explain to you right away. Yes, the question paper I’m referring is 0610/42/m/j/19 question 2 (part b). My confusion is regarding the explaining part of the question in which the mark scheme has referred to light, temperature and carbon dioxide as the limiting factor when the rate of reaction decreases,from the graph. Can u explain it? Also I have another question: Can you compare the development of fetus in early stages of pregnancy to its development in late stages of pregnancy?
         Thanks
         Nawalamir

         Reply

         1. Hi Nawalamir,

            Thank you for getting back to us. It’s clearer now.

            To answer your first questions we first need to understand that a limiting factor in biology is that variable/environmental condition that limits the growth, abundance, and development of a population/size. Therefore, increasing or decreasing the limiting factor has a direct positive/negative impact on the population/size.
            In this case, the limiting factors are those that affect the rate of photosynthesis in the experiment; Light, temperature, and carbon dioxide. Increasing or decreasing any of these environmental conditions has a direct influence on the rate of photosynthesis.

            On to the second question on a fetus during early vs late pregnancy.
            The early stages of the development of a fetus are called the embryonic stage. This is because the pluripotent cells of the embryo begin to differentiate into vital organs such as the limbs, heart (and the cardiovascular system), and the central nervous system (brain and spinal cord). Eventually, the embryo grows into a human-like form in the womb, though just about 2 inches long. If this stage is negatively affected the unborn child is highly susceptible to having a congenital disease after birth.
            The later stage is the fetal stage of development which is mainly focused on the growth and development of the fetus as cells continue to differentiate. The fetus grows in size, takes an even more vivid human-like form (enough to tell gender), and weighs about 2 pounds in the second trimester. The baby will move in the womb and prepare for birth.

            Hope this helps, we are here for you.

            Best regards,
            Biology Department

            Reply