Reproduction
This mindmap includes sexual and asexual reproduction, as well as reproduction in fungi, plants and malaria (which is needed for the new AQA GCSEs)
- Created by: lights321
- Created on: 07-01-18 18:21
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- Reproduction
- Organisms that reproduce both asexually & sexually depending on the
circumstance-s.
- FUNGI
- Many fungi reproduce asexually by spores ( most of the time) but sometimes also reproduce sexually to
give variation.
- In ASEXUAL reproduction, fungal spores are produced by mitosis & so are gentically identical to parent
- Most commonly seen asexual fruiting bodies full of spores: -toadstools -puffballs
- Some fungi also reproduce SEXUALLY when conditions aren't good.
- E.g. when it's dry, two hypha from different fungi join and nuclei fuse so new hypha has 2 sets of chromosomes. It undergoes meiosis to make haploid spores, each with only 1 set of chromosomeswhich are different from original hyphae. Some of the spores may produce fungi better adapted to survive the adverse conditions.
- In ASEXUAL reproduction, fungal spores are produced by mitosis & so are gentically identical to parent
- Fungi are made up of hyphae- a mass of thin threads.
- Many fungi reproduce asexually by spores ( most of the time) but sometimes also reproduce sexually to
give variation.
- PLANTS
- Many plants produce seeds sexually, but also reproduce asexually by runners such as strawberry plants, or bulb division such as daffodils.
- Sexual reproduction
- Advantage: Introduces variation & enables plants to survive as conditions change through natural selection.
- Asexual reproduction
- A new plant grows as a result of specially directed mitosis.
- ADVANTAGE: asexual reproduction means that new plants are formed even if the flowers are destroyed by frost, eaten or fail to be pollinated.
- DISADVANTA-GE: new plants are identical to their parent and no variation is introduced.
- MALARIA PARASITES
- Malarial parasites reproduce asexually in the human host, and also sexually in the mosquito. (Asexual reproduction is NOT an alternative only if conditions are bad).
- Malarial parasites spend part of their life cycle in the body of a female mosquito & part of their life cycle in the blood & organs of humans.
- Reproduce asexually in human liver & blood cells.
- When the mosquito takes her blood meal, the DROP IN TEMPERATURE between the human body & the mosquito triggers sexual reproduction in some of the parasites inside the red blood cells.
- There's a 20 minute window when sexual forms develop, burst out of the blood cells, & meet to form zygotes with 2 sets of chromosomes
- Zygotes then undergo meiosis to produce new asexual parasites that will infect a new human host.
- The parasites show a lot of VARIATION.
- Zygotes then undergo meiosis to produce new asexual parasites that will infect a new human host.
- There's a 20 minute window when sexual forms develop, burst out of the blood cells, & meet to form zygotes with 2 sets of chromosomes
- FUNGI
- Sexual
- Meiosis
- Gametes
- In plants the gametes are the egg cells and pollen.
- Gametes
- Advantages
- Produces variation in the offspring
- If the environment changes variation gives a survival advantage by natural selection
- Natural selection can be sped up by humans in selective breeding to increase food production.
- Meiosis
- Organisms that reproduce both asexually & sexually depending on the
circumstance-s.
- 1) The genetic information is copied so there are 4 sets of each chromosome instead of 2 normal sets. Each pair of chromosome forms a similar pair of chromatids. (This is very similar to Mitosis)
- Meiosis
- Gametes
- In plants the gametes are the egg cells and pollen.
- Gametes
- Meiosis
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