Login

|
|
Help pleaseModerator: BioTeam
9 posts • Page 1 of 1
Help pleaseHi, 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
Re: Help pleaseShoot 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
Re: Help pleaseIf you work your way backwards through the questions, you should be able to improve your answers.
3b should have some sort of reference to the introduction of genetic material by the pollinating plant and the genetic diversity that results...
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.
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
9 posts • Page 1 of 1
Who is onlineUsers browsing this forum: No registered users and 7 guests |
© Biology-Online.org. All Rights Reserved. Register | Login | About Us | Contact Us | Link to Us | Disclaimer & Privacy