Cellular Reproduction

Asexual Reproduction This is a type of reproduction where only one parent is involved. 100% of the genetic material from the one parent is passed on. There is no variation in the gene pool for the new offspring. Bacteria primarily reproduce asexually.

Sexual Reproduction This type of reproduction requires two parents. 50% of the genetic material is passed on from each parent There is a fair amount of genetic variation because new genes are integrated each generation. Most multi-cellular organisms reproduce sexually.

Examples of Asexual Reproduction Binary fission is asexual; the organism splits directly into two equal-sized offspring, each with a copy of the parent's genetic material. Binary fission is the usual type of reproduction in prokaryotes, the more familiar of which are known as bacteria.

Examples of Asexual Reproduction Budding is the formation of a new organism by the protrusion of part of another organism. This is very common in plants and fungi, and even an animal Hydra. The picture to the right is yeast budding. It’s almost like it’s growing out of the side of the yeast.

Hydra Budding Hydra is considered an animal and here it is budding. Notice the protrusion sticking out of the right side of the Hydra.

Examples of Asexual Reproduction Sporogenesis or Sporulation is when plants asexually produce small tiny spores on their outside leaves. These growths will usually detach from the organism and grow on another medium such as the ground. Some Fungi also sometimes undergo this process.

Examples of Asexual Reproduction Vegetative reproduction is a type of asexual reproduction for plants, and is also called vegetative propagation or vegetative multiplication. It is a process by which new plant "individuals" arise or are obtained without production of seeds or spores.

Examples of Asexual Reproduction Fragmentation is a type of asexual reproduction where each fragment develops into a mature, fully grown individual. This new individual is a clone of the original organism. If the organism is split any further the process is repeated. Sea Stars, Fungi, and some Worms do this.

Advantages of Asexual Reproduction Only one parent is required. This is good because it takes time and energy to find a mate. This can also be quite dangerous! If you have good genes it is great because 100% of them are passed on. Very quick reproduction

Disadvantages of Asexual Reproduction The main disadvantage is that there is no genetic variation. This means that if there is a genetic mutation or disease they are very hard to combat. Parents look entirely like offspring. If humans did this we would all look the same. (not much fun)

The Importance of Genetic Variation. As previously discussed, genetic variation is important because it allows individuals within a given species to adapt to their environment. Remember we are born with adaptations if don’t naturally have these differences in our DNA we can’t obtain them. If we are different because of genetic variation and we are able to adapt this is known as survival of the fittest or natural selection. Adaptations make organisms different and if it occurs over a long enough period of time we can get new species.

Sexual Reproduction Examples Organisms that reproduce sexually are animals and some plants. Even though plants are pollinated by bee’s and other insects this is still considered sexual reproduction.

Advantages to Sexual Reproduction With sexual reproduction you have more genetic variation. Both parents are passing on 50% of their genetic material so it’s easier to get rid of genetic mutations and diseases. This produces variation in the population. That way a species is more likely to survive if there are genetic differences in the population.

Disadvantages of Sexual Reproduction You have to expend time and energy to find a mate and in some cases fight for that mate. Think about rams that hit their heads together they are usually fighting over mating rights. (pretty dangerous) Planet Earth-Show Birds of Paradise Movie Only ½ your genes are passed on this is bad if you had great genes they can be diluted. Slow process.

Competition for Mating Rights Go home and look up the video Hippo Beach it’s pretty cool. I couldn’t access it here at school but you should be able to watch it at home.

Mini Movies on Cellular Reproduction Singled Celled Organisms Mini Movie Floral Arrangements Mini Movie The Red Queen Mini Movie