Asexual Reproduction Chapter 5.2

Asexual Reproduction Main points – Only one parent is required – Asexually produced offspring, or clones, have identical genetic information to each other and the parent – Reproduce quickly and in large numbers

5.2 Asexual ReproductionAsexual Reminder, most (~95%) of the time the cell is in interphase (doing its job, growing, surviving, etc.) Reminder, when the cell gets too big (If its volume outgrows its surface area), it must divide/reproduce

5.2 Asexual ReproductionAsexual is how the cells of multi-cellular organisms (like your body cells) reproduce and multiply is a common method of reproduction among single-celled organisms, such as the paramecium clone – offspring is an identical genetic copy of its parent clone E.g. used in agriculture and research to copy desired organisms, tissues and genes

Binary fission Budding Fragmentation Vegetative reproduction Spore formation Types of Asexual Reproduction

Binary fission – a single cell (unicellular) splits into identical copies (Ex. Bacteria) Video

Budding can occur in unicellular or multi-cellular organisms. Buds develop into a new organism (Ex. Hydra) Buds

Fragmentation Part of an organism breaks off due to injury The part grows into a clone of the parent Example: Starfish, milfoil

Vegetative reproduction -special cells in plants that develop into structures that form new plants identical to the parent (Ex. Spider plants, grafting fruit trees, -special cells in plants that develop into structures that form new plants identical to the parent (Ex. Spider plants, grafting fruit trees, runners and rhizomes, tubers and bulbs)

Spore formation - some bacteria, micro-organisms and fungi can form spores - single cells that can grow into a whole new organism (ex. Penicillium)

Asexual Reproduction See page 175

Human Assisted Cloning Two types: reproductive and therapeutic cloning Reproductive cloning - purpose is to produce a genetic duplicate of an existing or dead organism. Steps involved (adult DNA cloning) : 1.Remove nucleus from an egg cell 2.A mammary gland cell is removed from an adult female 3.Electricity fuses mammary and egg cell 4.Fused cell begins dividing 5.Dividing embryo is inserted into surrogate mother See pages

Reproductive Cloning

Therapeutic cloning purpose is to correct health problems – Stem cells cells that can become different types of cells can be used to replace cells damaged from injuries or disease – Diabetes, spinal injuries, Parkinson’s disease are only a few that can benefit from stem cell therapy – Controversial because the best stem cells are from embryos which are destroyed when harvesting cells See pages CloningCloning - debate

Therapeutic Cloning