1 / 12

Section 4 – Reproduction

Section 4 – Reproduction. National 4 & 5 - Multicellular Organisms. Learning Outcomes. By the end of this lesson I will be able to: - identify the difference between asexual & sexual reproduction - identify the sites of gamete production in plants

kaiser
Télécharger la présentation

Section 4 – Reproduction

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Section 4– Reproduction National 4 & 5 - Multicellular Organisms

  2. Learning Outcomes • By the end of this lesson I will be able to: • - identify the difference between asexual & sexual reproduction • - identify the sites of gamete production in plants • - identify the key structures of these sites • - explain what happens during fertilisation • - compare the methods of fertilisation in different plants

  3. Reproduction • The production of new members of a species • Can be sexual: • Requires sex cells (gametes) • These contain half the information needed to make a new organism • When they combine, a full set of information is formed • or asexual: • - does not require sex cells

  4. Gametes and reproduction • All body cells have two sets of chromosomes • - 1 set from each parent • These cells are said to be diploid • Gametes are formed by meiosis • - a type of cell division • Gametes contain one set of chromosomes • - half of the original cells • They are said to be haploid • When two haploid cells join together = fertilisation • A new diploid cell is formed • - this is a zygote

  5. Site of gamete production - plants • The reproductive parts of a plant are found in the flower • The male sex cells are found in pollen grains • These are found inside an anther • Female egg cells are called ovules • - found within the ovary

  6. Reproduction in plants - pollination • The transfer of pollen from an anther to a stigma • The stigma is the top of the female part of the flower • Pollen can be transferred in two ways • - by the wind • - by insects

  7. Insect Pollination vs. Wind Pollination INSECT WIND • What are the differences in appearance/structure between insect and wind pollinated flowers?

  8. Insect Pollination vs. Wind Pollination Complete the following table

  9. Insect Pollination vs. Wind Pollination Complete the following table

  10. Reproduction in plants - fertilisation It uses this to form a pollen tube • Once transferred, the pollen then needs to travel down the stigma • It uses sugar on the stigma as an energy source The male gametes then travel down to the ovule Once inside, the male and female sex cells join together This is fertilisation Plant sexual reproduction video

  11. Asexual Reproduction • When a new organism is produced from a single parent • Doesn’t involve sex cells or fertilisation • All offspring are identical to their parent • Plants • - also known as vegetative propagation • Plants can form offspring from their stems • E.g. runners from strawberry/spiderplant • Others can form offspring from their roots • E.g. onion , potato Plants asexual-reproductionvideo

  12. Asexual vs Sexual Reproduction Both types of reproduction have advantages

More Related