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    • #16725
      Olympic
      Participant

      Hi, I have done some questions and was wondering if someone would not mind having a look over them. I have answered them to my best ability. Hope they are not all wrong! 🙂
      Thanks a million.

      1Many fruits and vegetables are genetically identical.

      A ) state one way in which plants forming such fruits and vegetables are produced.
      B) state two advantages of producing plants in this way 

      Ans
      1a. A specialised part of the plant separates from the parent and grows by mitosis to form a new plant.

      Ans 
      1b The offspring formed in this way are genetically identical with the parent.

      2a In relation to flowering plants,
      Explain what is meant by vegetative propagation.

      2b Clones are genetically identical individuals. Are the products of vegetative propagation clones? Explain your answer. 

      Ans 
      2a is asexual reproduction in plants.
      An example of natural vegetative propagation that involve the stem are buttercups.
      Runners are horizontal stems that run or grow above ground and from which new plants grow.buds are formed at each node and may give rise to a new plant with its own root system

      Ans 
      2b  Yes as a specialised part of the plant separates from the parent and grows by mitosis to form a new plant. The offspring formed in this way are genetically identical with the parent.

      3. Give three reasons why seed reproduction is more complex than vegetative reproduction

      Ans; depend on outside agents. Eg pollination and dispersal
      Slow growth of the young plants to maturity
      Wasteful( petals, nectar, pollen, fruit)

      Explain why seed-grown plants often show more resistance to disease than plants that arise from vegetative propagation.

      Ans;  the offspring possesses variation and this assists plants to survive in a habitat by being better adapted. The seedlings may be resistant to a pathogen or be able to survive if climate conditions change.

      Suggest a biological reason for each of the following.

      A) growing plants from cuttings rather than from seeds

      Ans; to form new leaves and roots quickly

      B) removing leaves from a cutting before planting it in soil

      Ans; to reduce water loss 

      C) using growth regulators when growing cuttings

      Ans;  to speed up root formation

      D) grafting cultivated roses onto wild rose rootstock

      Ans; to combine the useful traits or qualities from the roses onto wild rose rootstock, eg large flowers grafted to wild rose with large roots but with small insignificant flowers

      E) cherry blossom trees may have white flowers on some branches and pink flowers in other branches

      Ans;  the offspring possess variations 

      F) growing plants by micropropagation

      Ans;) to produce large number of plants from small plant pieces. 

      G) plants that reproduce vegetatively  in nature may become overcrowded.

      Ans;) cos they reproduce rapidly

    • #111989
      JackBean
      Participant

      1b you’re answering with tautology

    • #111990
      Olympic
      Participant

      Shoot sorry

      1b identical plants produced are much more predictable than normal plants, so their yields are more reliable
      Plants that are resistant to pesticides can be reproduced more efficiently

    • #111993
      Darby
      Participant

      If you work your way backwards through the questions, you should be able to improve your answers.

    • #112031
      hymenoptera7
      Participant

      3b should have some sort of reference to the introduction of genetic material by the pollinating plant and the genetic diversity that results…

    • #112066
      Olympic
      Participant

      Thanks guys just wondering if these are correct?

      Why are babies tested for thyroxine levels?

       To measure the blood levels of thyroid hormone (T4) and TSH

      Why take extra iodine in the diet?

      Adequate levels of iodine ensure the proper functioning of the thyroid gland. Your thyroid regulates your metabolism. 

    • #112069
      JackBean
      Participant

      So, for question "Why should you use belt in car." you would answer "To use your belt."?

    • #112073
      Olympic
      Participant

      Thanks again. Is the baby one correct?
      Think the one below is a better answer for the iodine question

      To prevent getting  an enlarged thyroid gland, or goitre,  And also to prevent symptoms such as dry skin, hair loss, fatigue and slowed reflexes which is what you may get if have insufficient levels of iodine 

    • #112075
      JackBean
      Participant

      I was talking about the first question. The second one seems all right to me.

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