biology GCSE

• agar jelly

  substance in petri dishes used to culture microorganisms.
• cell differentiation

  process where a cell becomes specialised in its function.
• cell membrane

  partially permeable barrier that surrounds the cell.
• cell wall

  outer layer that strengthens plant cells.
• chloroplast

  site of photosynthesis
• concentration gradient

  difference in concentration between 2 areas.
• magnification

  how much bigger an object appears compared to the original object.
• mitochondria

  site of respiration
• nucleus

  found in most eukaryotic cells and contains the genetic material of the cell. controls the activities of the cell.
• plasmids

  loops of dna found in the cytoplasm of prokaryotic cells.
• resolution

  the ability to distinguish two different points in a specimen.
• specialised cells

  cells that are adapted to perform a specific function.
• surface area

  amount of contact an object has with its environment.
• therapeutic cloning

  producing an embryo that has the same genes as a patient.
• vacuole

  stores cell sap. storage found in plant cells.
• cellular respiration

  exothermic reaction that is continuously occurring in living cells.
• inverse proportion

  relationship between 2 values where one increases and the other decreases at the same rate.
• inverse square law

  as distance from a light source increases the light intensity is inversely proportional to the distance squared.
• limiting factor

  a factor that limits the rate of a reaction when there is not enough of it.
• metabolism

  the sum of all reactions in a cell.
• oxygen debt

  amount of extra oxygen the body needs after exercise to react with the accumulated lactic acid and remove it from the cells.
• photosynthesis

  endothermic reaction where energy is transferred from the environment to chloroplasts.
• amylase

  enzyme produced in the salivary glands and pancreas. it breaks down carbohydrates into simple sugars.
• benign tumour

  abnormal cell growth

  stays in 1 area

  is not cancerous
• blood

  a tissue containing red blood cells, white blood cells, platelets and plasma.
• cancer

  a non communicable disease caused by changes in the cell that lead to uncontrolled growth and division.
• cell

  basic building block of living organisms.
• communicable disease

  a disease that can be spread between individuals either directly or indirectly.
• coronary heart disease

  a disease caused by the build up of fatty deposits inside the coronary artery which narrows it and reduces blood flow to the heart.
• enzymes

  they increase the rate of reaction in living organisms.
• health

  the state of physical and mental wellbeing.
• heart

  an organ that pumps blood around the body in a double circulatory system.
• lipase

  an enzyme produced in the pancreas that breaks down lipids into fatty acids and glycerol.
• lock and key hypothesis

  a theory that describes how substrates must be the correct shape to fit the active site of an enzyme.
• malignant tumour.

  cancerous cell growth

  that invades neighbouring tissues

  can spread to different parts of the body in the blood.
• meristem tissue

  plant tissues containing undifferentiated stem cells

  used to produce clones quickly
• metabolism

  all of the chemical reactions occurring in an organism.
• non communicable disease

  a disease which cant be spread between individuals.
• organs

  group of tissues performing specific functions.
• organ systems

  group of organs that work together to form organisms.