2.3 - Energy Transformations Flashcards
What is Energy?
- Energy is the ability to do work, or produce a change. All cells require inputs of suitable forms of energy. This includes light energy for plant cells that contain chlorophyll, or chemical energy stored in complex molecules for animal cells.
What is Energy used for?
- Energy obtained by cells is used for processes such as movement, synthesis of materials and helps cells maintain a stable internal environment.
Can Energy be created or destroyed?
No, energy cannot be created or destroyed, it can only be transformed.
- Energy transformation or conversions occur with cells. eg. light energy into chemical energy in cell performing photosynthesis.
Does life require energy?
Yes, all life requires a continued input of energy to maintain cell (and therefore) life processes = life stops without the continued input of energy.
What are the forms of energy?
- Chemical energy
- Radiant (light) energy
- Heat (thermal) energy
- Kinetic
What is Chemical energy?
- This is the energy stored in the chemical bonds of complex molecules. Typically, carbohydrates and lipids in particular which contain usable amounts of energy for cells.
What is Radiant (light) energy?
- Light energy is a form of radiant energy that is radiated from the sun and transformed into chemical energy during photosynthesis. Some of this is transferred to the all animals via feeding relationships.
What is Heat (thermal) energy?
- This is the energy that is caused by the movements of atoms or molecules in a substance. Heat energy increases as atoms vibrate faster or molecules move faster; this has implications for all metabolic reactions.
What is Kinetic energy?
- This is the energy associated with the movement of molecules, cell components or whole objects; including organisms. Energy may be required to move molecules, for example, in specific directions eg. Into a cell or to move chromosomes during cell division.
What organic molecules do organisms require in order to survive and carry out daily processes and activities?
- Carbohydrates, lipids, proteins, and nucleic acids
What are Autotrophs?
- Autotrophs are organisms that produce their own energy rich compounds from inorganic materials.
- Transforms chemical energy for use through aerobic respiration.
What are Photosynthetic Autotrophs?
- Photosynthetic Autotrophs use energy from the sunlight to carry out photosynthesis to produce a chemical store of energy. Most autotrophs are photosynthetic autotrophs.
what are Chemosynthetic Autotrophs?
- Chemosynthetic Autotrophs oxidise chemical to obtain a chemical store of energy.
What are Heterotrophs?
- Heterotrophs need to consume other organisms to obtain their supply of organic molecules as they are unable to manufacture these from raw inorganic materials.
- In a food chain, heterotrophs feed on other heterotrophs or on autotrophs (producers)
- Ultimately all heterotrophs rely on autotrophs for the supply of energy rich compounds. Therefore photosynthesis is important for life on earth.
- Transforms chemical energy for use through aerobic respiration.
What is Photosynthesis?
- The light energy that falls on and is absorbed by cells in the leaves of plant enables the process of photosynthesis to occur.
- Photosynthesis is the process where, light energy is trapped by the green pigment of chlorophyll and this enables light energy to be transformed into chemical energy which is stored in the chemical bonds of organic molecules like glucose and starch.
What are Chloroplasts?
- Chloroplasts are the membrane-bound organelles which are the site of photosynthesis.
- They are abundant in the mesophyll tissue of leaves, arranged in layers in order to maximise their exposure to light energy that passes through the upper surface of the leaf.
What are Guard Cells?
- Guard cells regulate the opening and closing of the stomates, and they are clearly visible in the lower epidermis.
- When stomate are open, gas exchange, essential for the process of photosynthesis to occur.
What is the Chemical Equation for Photosynthesis?
6CO2 + 6H2O ———Sunlight + Chlorophyll- ———> C6H12O6 + 6O2