Classification of Living Things

Classification of Living Things

• Organisms are classified based on their characteristics.
• Understanding organisms is achieved through classification.

Classification of Animals

• Animals are classified into those with backbones and those without.
• Vertebrates include birds, fish, mammals, reptiles, and amphibians.
• Invertebrates include insects.
• Insects have three pairs of legs and a pair of antennae.
• Insects' bodies consist of a head, thorax, and abdomen, with some having wings.
• Fish live in water, swim with fins, breathe with gills, and are covered in scales.
• Birds have feathers, beaks, wings, legs, and breathe with lungs.
• Mammals have hair, breathe with lungs, and females produce milk for their young.
• Reptiles have dry, scaly skin and breathe with lungs.
• Amphibians have moist skin without scales, with adults breathing through lungs and skin.

Classification of Plants

• Plants are classified as flowering or non-flowering.
• Common flowering plants include daffodils, roses, and sunflowers, which vary in shape, color, and flowering times.
• Non-flowering plants include mosses, ferns, and pines.
• Plants are also categorized as land or water plants.

Plants and Environment

• Plant growth is affected by temperature and rainfall.
• Deserts and polar regions have sparse plant growth.
• Tropical rainforests have a wide variety of plants that form dense forests.
• Plants in dry places have deep or shallow roots to absorb water.
• Root adaptation: desert plants have deep roots to absorb water deep in the ground, or shallow roots spread over a wide area to absorb water quickly.
• In tropical rainforests, buttress roots support tall trees to get more sunlight.
• Wetland plants have aerial roots to absorb oxygen from the air.
• Stem adaptation: desert cacti have thick stems to store water.
• In tropical rainforests, climbing plants twine around trees to reach more sunlight.
• In wetlands, lotus stems have holes for gaseous exchange.
• Leaf adaptation: desert plants have needle-shaped leaves to reduce water loss.
• Tropical rainforest plants have broad, smooth leaves to shed rainwater and get more sunlight.
• Wetland plants have waxy leaves to reduce water loss due to high salt content in the soil.
• To protect themselves from animals, some plants are poisonous.
• Himalayan nettles have spikes on their stems.
• Plants such as lithops look like stones, aiding in protection.

Animals and Environment

• Animal survival relies on climate, water supply, and food.
• Polar bears have thick fur and fat for warmth.
• Some animals like squirrels and snakes enter deep sleep to conserve energy.
• African tortoises have thick scales and hard shells to minimize water loss.
• Camouflage helps animals hide from others via color, or shape.
• Examples include mimicry, warning colors, and living in groups.
• Lions' sharp teeth help in ripping and biting prey.
• Sawfish use their saw-like structure to hit and kill prey.