Transcript File
CHAPTER 3.2 Part I ENERGY FLOW I.WHERE DOES THE ENERGY COME FROM FOR EVERY ORGANISM TO INTERACT A. SUNLIGHT is the main energy source for LIFE 1. Less than 1% of sunlight is used by living things 2. Photosynthesis – the process of obtaining light energy to make food. B. CHEMICALS are another source of energy 1. Chemosynthetic bacteria can convert energy from chemicals through a process called chemosynthesis II. WHO MAKES THE ENERGY A. AUTOTROPHS (PRODUCERS) 1. Plants (Sunlight) 2. Some Algae (sunlight) 3. Some Bacteria (breaking down chemicals – where no sunlight is found) B. Without AUTOTROPHS or a constant input of energy, living things cannot function (live) III. WHO USES THE ENERGY MADE FROM AUTOTROPHS A. CONSUMERS or HETEROTROPHS 1. They rely on other organisms for food and energy 2. Animals, Fungi, bacteria, protists B. 5 TYPES of Heterotrophs 1. 2. 3. 4. 5. HERBIVORE CARNIVORE OMNIVORE DETRITIVORE (scavenger) DECOMPOSER Eat plants Eat Animals (meat) Eat Animals and Plants Feed on dead matter (detritus) Break down organic matter or dead things IV. ENERGY FLOW!!!! A. FOOD CHAIN – energy stored by autotrophs can be passed on through an ecosystem along a food chain. B. FOOD WEB – combination of food chains in an ecosystem **Energy flows in ONE direction from the autotrophs through the consumers! Food Chains ,Food Webs,Energy Pyramid in Ecosystems-Video for Kids – YouTube Reminder Stop at 3:00 V. TROPHIC LEVELS 1. Each step in a food chain or web is called a trophic level 2. Producers are always in the first trophic level 3. Herbivores or omnivores are in the second trophic level 4. Other consumers (omnivore or carnivore) are in third, fourth,… higher trophic level. VI. Levels of ConsumerDepends on Food Chain – what was just eaten 1. 1st Order Consumer - eats producer (2nd TL) 2. 2nd Order Consumer – eats 1st order consumer 3. 3rd Order Consumer – eats 2nd order consumer 4. 4th order consumer… Where do the arrows point? What level of consumer are they? What are the trophic levels? Level of Consumer Trophic level Level of Consumer Trophic level 1st TL 1st -Order 2nd - Order 2nd T.L. 3rd T.L 2nd -Order 3rd TL 3rd- Order 4th T.L 1st - Order 2nd TL 1st TL 3rd Trophic Level 1st Trophic Level 2nd Trophic Level Food Webs The top of the food chain. Some animals are said to be at the top of the food chain. This is because they are not hunted by other animals. What are some examples? LION - Can you think why? HUMAN – can you think why? HAWK – Can you think Why? Breaking the Chain Organisms living in a habitat depend on each other. If one part of a food chain dies out or is greatly reduced, the consumers have to find alternative food, move away, or starve. This then affects more consumers in the same way.