Living Environment

• Biotic factors are living factors that affect another organism or shape the environment, such as animals, plants, bacteria, and fungi.
• Abiotic factors are non-living factors that affect organisms, such as temperature, light intensity, water, soil pH and mineral content, and gases.
• Organisms are well adapted to live in specific environments, therefore any change in these factors can affect the organism.
• An increase or decrease in temperature can affect organisms that are well adapted to live in specific climates, which can result in migration.
• A reduction in light intensity can affect the rate of photosynthesis, which will ultimately affect food availability.
• Both plants and animals need water for survival, therefore a change in the water level can also affect organisms.
• Soil pH and minerals in the soil are an important abiotic factor for plants, with different plants needing a specific pH and minerals in the soil.
• Carbon dioxide is a gas that plants require for photosynthesis, therefore a decrease in carbon dioxide level will also affect the rate of photosynthesis.
• A fall in the level of oxygen, for example on hot days, can affect sea organisms.
• Animals are generally heterotrophs, also known as consumers.
• Fungi are also heterotrophs.
• Some protists are heterotrophs and some bacteria and some Archaea are also heterotrophs.
• Not everything on this planet is a heterotroph, some organisms are autotrophs, also known as producers.
• Plants are generally autotrophs, they make their own food using light as their source of energy.
• Carnivorous plants are still producers, they produce their own food using photosynthesis, but they can also digest insects to obtain nitrogen.
• Nitrogen is an important element that living organisms need, and most carnivorous plants live in areas where there is low nitrogen in the soil.
• Some protists are autotrophs, some bacteria and some Archaea are also autotrophs.
• An organism can be both an autotroph and a heterotroph, for example, Euglena can do photosynthesis as autotrophs, but they can also be heterotrophs and consume organic matter in cases where light is not available.
• Cellular respiration processes can vary, it may involve oxygen, no oxygen, different electron acceptors.
• Photoheterotrophs will do some form of cellular respiration to further break down their food to generate ATP.
• Humans are examples of chemoheterotrophs as they consume organic matter and organic compounds act as their energy source.
• Photoheterotrophs are found in a few types of prokaryotes.
• Photoheterotrophs are heterotrophs which consume organic matter and their energy source is light.
• Autotrophs and heterotrophs obtain carbon differently, with autotrophs generally using an inorganic source of carbon to make their food and heterotrophs having to get their carbon from organic sources that they consume.
• The terms photoautotroph and chemoautotroph refer to the organism’s energy source, with plants being an example of a photoautotroph as they use light as their energy source.
• Ich is a disease that can afflict aquarium fish, caused by a parasitic protist.
• The first time my fish caught Ich, it spread to all of my beloved fish, including Gertrude.
• Ich is contagious in fish, typically causing white dots on their bodies, fins, and gills.
• Ich can be lethal if not treated, making it a serious concern for fish enthusiasts like me.
• One common treatment for Ich contains an antiparasitic called methylene blue, which is quite blue and spreads on its own through a process called diffusion.
• Diffusion is when the net movement of a substance travels down its concentration gradient, moving from a high concentration to a low concentration until equilibrium is reached.
• The methylene blue drops spread in the water, reaching all of the fish and treating them.
• Diffusion occurs if you spray an air freshener in the air, with the net movement of molecules traveling from an area of high concentration to a low concentration of the air freshener.
• Diffusion is a passive transport, meaning an input of energy is not needed.
• When we talk about diffusion of molecules in cells, such as the diffusion of oxygen molecules into a cell, it is classified as passive transport.
• A concentration gradient is a form of potential energy.
• Passive transport is different from other processes like active transport where an input of energy is required.
• The characteristics of the solvent can affect the rate of diffusion, as a dense solvent can slow the molecules down and decrease the diffusion rate.
• Diffusion is responsible for many critical items, such as oxygen leaving the alveoli of the lungs to the blood and the waste gas carbon dioxide exiting the blood to the alveoli.
• The characteristics of the molecules can affect the rate of diffusion, as a substance with a greater mass generally has a lower diffusion rate when compared to a substance with less mass.