Biology Topic 2 Definitions Flashcards
(23 cards)
Respiration that needs oxygen
Aerobic respiration
A simple sugar that is broken down in cells to release energy during respiration.
Glucose
Tiny blood vessels with thin walls to allow diffusion of substances into and out of the blood
Capillaries
The random movement and spreading of particles. Where there is a concentration gradient there is diffusion of particles from areas of high concentration to regions of low concentration
Diffusion
A situation where a solute is in a gradually increasing concentration for one region to another
Concentration gradient
A process in the lungs in which oxygen diffuses from the lungs into the blood and carbon dioxide diffuses from the blood into the lungs
Gas exchange
The volume of blood the heart can pump out with each beat
Stroke volume
The volume of blood the heart can pump out in one minute.
Cardiac output = stroke volume x heart rate
Cardiac output
Period of time after exercise in which a greater amount of oxygen than usual is needed by body for various processes, including the removal removal of lactic acid cell repair. Used to be known as oxygen debt.
Excess post-exercise oxygen consumption
EPOC
A carbohydrate made by joining thousands of glucose molecules
Starch
A series of enzyme-catalysed reactions carried out in green parts of a plant. Carbon dioxide and water combine to form glucose. Process requires light energy from sun
Photosynthesis
Organelle in plant cells that contains chlorophyll and is where photosynthesis takes place
Chloroplasts
Green substance in chloroplasts that absorbs energy from sunlight
Chlorophyll
A tiny pore in lower surface of leaves which allows gases to diffuse into and out of the leaf when open
Stomata
Total amount of surface area divided by its volume
Surface area to volume ratio
A single factor that when in short supply can limit the rate of a process such as photosynthesis. An example of this is light intensity
Limiting factor
Cells found near the tip of roots that have extensions. Water enter the root hair cells by osmosis and they have a large surface area
Root hair cells
The diffusion of water from a region of high concentration to a region of low concentration through a partially permeable membrane
Osmosis
A thin sheet of material that allows small molecules through (water) but not larger ones
Partially permeable membrane
Movement of molecules into the cell using energy from respiration
Active transport
Tissues made of dead hollow and dissolved minerals from the roots to other parts of the plant
Xylem
Long tissue that transports sugars around a plant
Phloem
A series of reactions occurring in all living cells in which glucose is broken down to release energy.
Respiration