Adaptation and Inheritance

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Competition and Inheritance

What animals compete for- in habitat limited supply of resources, animals compete for things such as food, water, space/shelter and mates (to reproduce).

What plants compete for- they compete for light, water, space and minerals

Best competitors: Fast, strong and quick to spot prey. this allows them to spot prey quick and attack. spotting prey may require good eyes and hearing. These are adaptations of animals that are good at getting food.

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Adapting to change:

How animals and plants cope in the seasons/change:

Tree- In the spring they grow rapidly as it is warm and wet. they lose their leaves in the winter. This saves energy. The fallen leaves protect base of tree and give nutrients.

Animals- In the cold they hibernate, migrate and grow thick fur. Hibernation is when animals find warm place for winter. Migration is when animals such as birds fly to warm countries.

Organisms- You can lose home due to climate change. Food supply could decrease idue to diseases

Predator-prey relationship: animas adapt to changes in food supply. Only best competitors survive to reproduce. Interdependance between predator and prey is when predator eats only 1 prey. This means population of 1 animal effects another.

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Variation

How organisms vary- Differences in characterisation (variation). Easier to tell between some organisms than others because they're different species. However its harder to tell between organisms of the same species or breed.

How humans vary- Every human different, even identical twins.

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Continuous and Discontinuous

Discontinuous variation- Characteristics that only result in certain values show discontinuous variation. For example gender, you are either male or female.

Continuous Variation- Characteristics that can take any value within a range is continuous variation. For example height ranges from the shortest person to the tallest person.

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Inheritance

You inherit characteristics from your parents genetic material in the the nucleus of your cells. This material is a chemical called DNA (deoxyribonucleic acid). DNA contains information to make organisms.

Chromosomes. Different species have different number of chromosomes in their nucleus. Humans have 46, cats have 38. You inherit half fom your dad and half from your mum.

Genes- Each chromosome is divided into sections of DNA. The sections that hold the info are called genes. For example, one gene contains the info of your eye colour.

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Natural Selection

Evolution- When species gradually develop over millions of years. Evolution started with unicellular organisms. These organisms similar to bacteria, lived in water more than 3 billion years ago. Over time they turn into multicellular organisms. Eventually they evolved into animals.

How organisms evolve- They evolve through a process called natural selection. They change slowly over time, to adapt to their environment. The process takes many years sometimes millions.

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Extinction

Extinction- If a soecies isn't adapted to its environment it wil not survive. Eventually the species will become extinct as there is no more of them for example the dodo bird.

How we know extinct species existed- We know because of fossils. Fossils are the skeletons of creatures buried in the ground.

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