Biology: Adaptation and Mutations

Adaptation for Survival

• Living things develop special features or adapt to their habitats over time to survive.
• Examples of adaptations include: • African elephant's large ears to keep cool in hot habitats. • Polar bear's thick fur to keep warm in cold habitats. • Cactus's shallow roots and water-storing stem to survive in desert environments.

Mutations

• Mutations are permanent changes in the DNA sequence.
• They can be: • Neutral, having no effect on the organism. • Positive, providing an advantage. • Negative, causing a disadvantage.
• Environmental factors like radiation and chemicals can increase the rate of mutation.
• Examples of mutations include: • Plants developing resistance to bacterial and fungal infections (positive mutation). • Cancer, caused by mutations in genes that regulate the cell cycle (negative mutation). • White fur of the Kermode (Spirit) bear, which is usually black (neutral mutation).

Theory of Natural Selection

• Evolution is explained by Darwin's theory of natural selection.
• The theory focuses on how variations benefit individuals to survive environmental changes, predation, or competition.
• Individuals with successful variations produce more offspring, passing the variation on to the next generation.
• This process allows the population to evolve with the successful variation.

Darwin's Discoveries

• Charles Darwin published "On the Origin of Species" in 1859, explaining his theory of natural selection.
• Darwin's theory shows how all living things are connected in a family tree that stretches back billions of years to the beginning of life on Earth.
• One of Darwin's discoveries was the identification of fourteen different species of Finches in the Galapagos Islands, each with adaptive beaks for their eating habits.
• Examples of adaptive beaks include: • Strong and sturdy beaks with a chisel-like tip for drilling holes in wood (woodpecker). • Shorter, stouter beaks for eating seeds found on the ground. • Long, pointed beaks for picking seeds out of cactus fruits.

This quiz covers the concept of adaptation in living organisms and its importance for survival. It also touches on mutations and their effects on the DNA sequence. Test your knowledge of these biological concepts!