biology+enzyme

• The active site is where substrates bind to an enzyme, forming an enzyme-substrate complex (ES).
• Catalytic activity refers to the ability of an enzyme to increase the rate of a specific biochemical reaction.
• Enzymes are biological catalysts that speed up chemical reactions without being consumed or altered by the reaction.
• Enzymes are proteins that catalyze chemical reactions by lowering the activation energy required for the reaction.
• Enzymes have specific shapes and can only interact with certain molecules called substrates.
• Substrates must fit into the active site of an enzyme like a key fits into a lock.
• Enzymes have a unique three-dimensional structure called their tertiary structure, which determines their shape and function.
• Enzymes are biological catalysts that speed up chemical reactions without being consumed or altered by them.
• Enzymes can be denatured when exposed to extreme temperatures, pH levels outside their optimal range
• Denaturation causes enzymes to lose their catalytic activity and become inactive.
• There is a hierarchical structure for life that organises itself from cell organelles

  → to cells → to tissues → to organs → to organ systems → to organisms and even through to ecosystems.
• Single celled organisms do not form specialised tissues

  however, they are adapted to their environment by other means.
• Single celled organisms can relinquish all their waste and gain most, if not all, their nutrient requirements via diffusion and osmosis with the environment.
• All cells have a high surface area to volume ratio (SA:V) however each unicellular organism has direct access to the environment via their membrane where they will gain all their food and eliminate all their waste.
• Since the majority of cells in a multicellular organism do not have direct access to the outside environment, they have to gain all their nutrition and release all their wastes to the internal environment of the organism.
• Many different types of tissues often work together to carry out specialised functions for multicellular organisms and are termed organs e.g. heart and stomach.
• DNA/RNA → Organelles → Cells →Tissues → Organs → Organ systems → Organisms
• Sends messages from your sense organs: Nervous System = nerves and neurons
• Gets rid of wastes from the body: Excretory System
• Changes the food you eat into a form that the body can use: Digestive System
• pH of a neutral solution is 7
• On the pH scale, the smaller the number, the higher the acidity.
• On the pH scale, objects that arent very acidic are refered to as basic
• Unicellular organisms contain only one cell. Unicellular organisms do not have tissues or organs but can still have specialised organelles that allow them to be better suited to the environment.