BBC Bitesize - GCSE Biology (Single Science) - Food chains - Revision 1
Ecosystem: The collection of all living organisms in a geographic area, together with all the living and Comprise of organisms that feed on dead matter and break it down to release chemical FEEDING RELATIONSHIPS AMONG SPECIES. between living and non-living things within an ecosystem. METHOD AND . The biotic component of ecosystems contains all of these communities of . is, they feed on or break down dead plant or animal matter, thus making organic nutrients . Learn how food chains show the feeding relationships between living things with The other organisms in a food chain are consumers, because they all get their organisms, and on the undigested parts of plant and animal matter in faeces.
Omnivores eat both animals and plants. Once again, knowing the Latin root helps a lot: For example, an insectivore is a carnivore that eats insects, and a frugivore is an herbivore that eats fruit. This may seem like a lot of terminology, but it helps scientists communicate and immediately understand a lot about a particular type of organism by using the precise terms. Not all organisms need to eat others for food and energy.
Some organisms have the amazing ability to make produce their own energy-rich food molecules from sunlight and simple chemicals. Organisms that make their own food by using sunlight or chemical energy to convert simple inorganic molecules into complex, energy-rich organic molecules like glucose are called producers or autotrophs.
Some producers are chemosynthesizers using chemicals to make food rather than photosynthesizers; instead of using sunlight as the source of energy to make energy-rich molecules, these bacteria and their relatives use simple chemicals as their source of energy. Chemosynthesizers live in places with no sunlight, such as along oceanic vents at great depths on the ocean floor.
No matter how long you or a giraffe stands out in the sun, you will never be able to make food by just soaking up the sunshine; you will never be able to photosynthesize.
Producers use the food that they make and the chemical energy it contains to meet their own needs for building-block molecules and energy so that they can do things such as grow, move, and reproduce. All other life depends on the energy-rich food molecules made by producers — either directly by eating producers, or indirectly by eating organisms that have eaten producers.
Not surprisingly, ecologists also have terms that describe where in the food chain a particular consumer operates. A primary consumer eats producers e. And it can go even further: A single individual animal can act as a different type of consumer depending on what it is eating. When a bear eats berries, for example, it is being a primary consumer, but when it eats a fish, it might be a secondary or a tertiary consumer, depending on what the fish ate!
All organisms play a part in the web of life and every living thing will die at some point. This is where scavengers, detritivores which eat detritus or parts of dead thingsand decomposers come in. They all play a critical role that often goes unnoticed when observing the workings of an ecosystem. They break down carcasses, body parts and waste products, returning to the ecosystem the nutrients and minerals stored in them.
This interaction is critical for our health and health of the entire planet; without them we would be literally buried in dead stuff. Heat moves in predictable ways, normally flowing from warmer objects to cooler ones, until the objects reach the same temperature. Human activities change land cover and land use patterns, add or remove nutrients from ecosystems and modify some of the fundamental cycles of the earth system, including the carbon cycle.
These changes can have unexpected and far-reaching effects due to the complex interconnections among earth systems. In a technological world, inventions and innovations must be carefully assessed by individuals and society as a whole. Innovation is the process of improving an existing product, process, or system.
Innovation is the process of modifying an existing product, process, or system to improve it.
Interaction of circulating air masses gives rise to a wide variety of weather phenomena including fronts, mid-latitude cyclones and anti-cyclonesand severe weather tropical storms, tornados, severe thunderstorms, etc. Invention is a process of creating new products, processes, or systems.
- Food chains
- Ecological interactions
Invention is a process of turning ideas and imagination into new products, processes, or systems. Inventions and innovations must be carefully assessed by individuals and society.
Large scale wind patterns drive surface currents in the oceans and affects weather.
Manufacturing is the process of turning materials into useful products. Manufacturing is the process of turning raw materials into useful products. Mass is a measure of the amount of matter in an object.
Food chains & food webs
Mechanical advantage, using less force over a greater distance, allows the same work to be performed with less effort. Moving electric charges produce magnetic forces and moving magnets produce electric forces. People select, create, and use technology. Plants transform light energy into chemical energy, which then can be used by other living things. Safety is a preeminent concern for all technological development and use. Safety is one of the most important concerns for all technological development and use.
Science and technology are interconnected. Simple machines help accomplish a task with less effort by either changing the direction of motion or increasing the mechanical advantage. Others are gradual, such as the lifting up of mountains or their wearing away by erosion.
Some organisms are made up of only one cell. Specialized cells perform specialized functions in multicellular organisms.
Technological literacy is necessary for a productive workforce. Technological literacy is necessary for all citizens. Technological literacy is the ability to understand, use, assess, design, and create technology. Technological literacy requires lifelong learning. Technology and society impact each other.
The abilities required in a technological world include diagnosing, troubleshooting, analyzing and maintaining systems. The abilities required in a technological world include understanding, fixing, and maintaining systems.
The atmosphere circulates in large scale patterns which steer weather systems due to heat from the sun. The circulation of the ocean and atmosphere carries heat energy and has a strong influence on climate around the world.
The cycling of water in and out of the atmosphere plays an important role in determining climatic patterns. The gene is the basic unit of inheritance. The goal of technology is to meet human needs and wants. The gravitational force is a universal force that depends on how much mass the objects have and how far apart they are.
The magnitude of the gravitational force is weight oz, lb, newtons. Some organisms, called autotrophs, also known as self-feeders, can make their own food—that is, their own organic compounds—out of simple molecules like carbon dioxide. There are two basic types of autotrophs: Photoautotrophs, such as plants, use energy from sunlight to make organic compounds—sugars—out of carbon dioxide in photosynthesis.
Other examples of photoautotrophs include algae and cyanobacteria. Chemoautotrophs use energy from chemicals to build organic compounds out of carbon dioxide or similar molecules. This is called chemosynthesis. For instance, there are hydrogen sulfide-oxidizing chemoautotrophic bacteria found in undersea vent communities where no light can reach. Autotrophs are the foundation of every ecosystem on the planet. That may sound dramatic, but it's no exaggeration!
Autotrophs form the base of food chains and food webs, and the energy they capture from light or chemicals sustains all the other organisms in the community. When we're talking about their role in food chains, we can call autotrophs producers.
THE ECOSYSTEM: INTERRELATIONSHIPS BETWEEN
Heterotrophs, also known as other-feeders, can't capture light or chemical energy to make their own food out of carbon dioxide. Instead, heterotrophs get organic molecules by eating other organisms or their byproducts. Animals, fungi, and many bacteria are heterotrophs. When we talk about heterotrophs' role in food chains, we can call them consumers. As we'll see shortly, there are many different kinds of consumers with different ecological roles, from plant-eating insects to meat-eating animals to fungi that feed on debris and wastes.
Food chains Now, we can take a look at how energy and nutrients move through a ecological community. Let's start by considering just a few who-eats-who relationships by looking at a food chain. A food chain is a linear sequence of organisms through which nutrients and energy pass as one organism eats another. Let's look at the parts of a typical food chain, starting from the bottom—the producers—and moving upward. At the base of the food chain lie the primary producers.
The primary producers are autotrophs and are most often photosynthetic organisms such as plants, algae, or cyanobacteria. The organisms that eat the primary producers are called primary consumers. Primary consumers are usually herbivores, plant-eaters, though they may be algae eaters or bacteria eaters.