MAEVA BIO REVISION PDF

1. Define and give examples of: Filter feeders: Animals that strain tiny food particles from water using structures like modified gills or nets. Examples: Sponges, blue whales. Cnidarians: Aquatic invertebrates with tentacles and stinging cells used for capturing prey....

1. Define and give examples of: Filter feeders: Animals that strain tiny food particles from water using structures like modified gills or nets. Examples: Sponges, blue whales. Cnidarians: Aquatic invertebrates with tentacles and stinging cells used for capturing prey. Examples: Jellyfish, sea anemones. Ruminants: Herbivorous mammals with a specialized stomach for digesting cellulose, involving re-chewing (regurgitation and rumination). Examples: Cows, giraffes. Herbivores: Animals that feed on plants or algae. Examples: Kangaroos, rabbits. Carnivores: Animals that eat other animals, using sharp teeth or venom to catch and consume prey. Examples: Wolves, spiders. Omnivores: Animals that eat both plants and animals. Examples: Bears, humans. Detritivores: Animals that feed on decomposing organic material. Examples: Earthworms, millipedes. 2. Distinguish between carnivore and herbivore mouthparts and explain how each helps digestion: Feature Carnivores Herbivores Incisors - Small and less prominent. - Large, chisel-shaped incisors. - Used for nibbling or - Used to clip or cut plant scraping meat from bones. material like leaves or stems. Canines - Long, sharp, and pointed. - Small or absent (depending on - Used to pierce, grip, and species). tear prey. Molars & - Sharp and jagged edges. - Broad and flat surfaces. Premolars - Act like scissors to slice - Used for crushing and grinding through muscle and bone. tough plant fibers. Jaws - Short, strong jaws. - Longer jaws that allow - Primarily move up and side-to-side grinding motion in down to deliver a powerful addition to up-and-down shearing bite. movements. Skull Shape - Narrow skull to maximize - Elongated skull to biting force with sharp teeth accommodate chewing muscles alignment. and flat teeth. Tongue - Rough or textured to scrape - Smooth or soft to manipulate and clean meat off bones. and push plant material for grinding. Other - Sharp claws or gripping - Diastema (gap between Adaptation structures to hold prey while incisors and molars) to help s chewing. move food back for grinding. Digestive - Optimized to cut through - Designed to efficiently break Purpose and process high-protein down tough cellulose and fibrous diets quickly. plant material for digestion. 3. How do microbiome bacteria benefit digestion? - Microbiome bacteria aid by: - Breaking down complex carbohydrates like cellulose. - Producing essential vitamins, like Vitamin K and certain B vitamins. - Boosting immunity by competing with harmful bacteria. - Facilitating nutrient absorption. 4. Food processing in humans, ruminants, birds, sponges, and cnidarians: Humans: Digest food using a one-way system involving the mouth, stomach, intestines, and enzymes. Ruminants: Use a multi-chambered stomach (rumen) for fermenting plant material with the help of microbes. Birds: Use a specialized crop (for storage) and gizzard (for grinding food). Sponges: Filter feed by drawing water through pores and trapping particles. Cnidarians: Use a gastrovascular cavity where food is digested and nutrients are absorbed. 5. One specific digestive feature of each: -Humans: Enzymes in saliva start breaking down carbohydrates in the mouth. - Cnidarians: Gastrovascular cavity for digestion and absorption. - Sponges: Choanocytes (collar cells) filter food particles from water. - Birds: Gizzard uses grit to grind food. - Ruminants: Rumen contains microbes to digest cellulose.