Science combined

• What is osmosis?

  Osmosis is the movement of water molecules from an area of lower solute concentration to an area of higher solute concentration across a semi-permeable membrane.
• What is meisis?

  Sexual reproduction
• What is aseptic technique?

  Aseptic technique is a set of practices used to prevent contamination and maintain sterility in medical procedures or laboratory settings.
• What is diffusion?

  Diffusion is the movement of particles from an area of high concentration to an area of low concentration.
• What are the difference between malignant tumours and benign tumours?

  Malignant: cancerous, invasive, can spread Benign: non-cancerous, non-invasive, does not spread
• What are stem cells? An undifferentiated cell that can form into other cell types.
• What is the nucleus?

  A membrane bound structure that contains DNA and controls cell's activities.
• What factors increase the rate of diffusion?

  Temperature, concentration gradient and greater surface area.
• What is mitosis?


  Mitosis is the process of cell division in which a single cell divides into two identical daughter cells. It is asexual reproduction.
• What is a meristem?

  Stem cells found in plants that can develop into all plant cells.
• What is the function of a quadrat?


  It provides a known area in which to count the number of individual species.
• What is an indicator species?


  A species that provides information about the health of an ecosystem.
• Where can stem cells be found?

  Embryos, bone marrow, and umbilical cord blood.
• What is Newton's First Law?

  An object will remain in the same state of motion unless acted on by an external force.
• What is Newton's Third Law?

  Every object has an equal and opposite reaction.
• What are risk factors?


  Factors that increase the likelihood of a negative outcome or event.
• What are examples of lifestyle risk factors?

  Smoking, poor diet, lack of physical activity, excessive alcohol consumption, UV exposure.
• What is a partially permeable membrane?

  A membrane that allows only certain substances to pass through while blocking others.
• How to calculate relative atomic mass?
• How to calculate relative atomic mass?

  Sum of (mass of each isotope x abundance) divided by 100.
• What is an isotope?

  An isotope is a variant of an element that has the same number of protons but a different number of neutrons in its nucleus.
• What is equilibrium?

  Balance
• What is inertia?


  The tendency for an object to continue in the same state of motion.
• What is a resultant force?

  The overall effect of a force.
• What is the difference between balanced and unbalanced forces?

  Balanced forces have equal magnitude and opposite direction, resulting in no change in motion, while unbalanced forces have unequal magnitude or direction, resulting in a change in motion.
• Efforts are being made into the protection and regeneration of rare and threatened.
• Farmers are being incentivised to maintain field margins and hedgerows, as these habitats can support biodiversity.
• What do decomposers secrete to break down organic matter?

  Enzymes
• When animals and plants die, decomposers return the carbon locked in their bodies back to the atmosphere via decay.
• Combustion of fossil fuels is another source of carbon entry into the atmosphere.
• Carbon is returned into the atmosphere (as carbon dioxide) because of the respiration that happens in plant and animal cells.
• The burning of trees and decomposition of wood increases the rate that carbon dioxide is released into the atmosphere.
• The growth stage occurs before mitosis. In this stage extra sub-cellular structures are produced.
• 1The two sets of chromosomes are separated by being pulled to opposite ends of cell.The nucleus divides in two.3The cytoplasm and cell membranes divide.4Two identical cells are created.
• What is the meaning of the term 'plateaus'?

  a part of a graph in which the value of the ordinate shows little or no change with increasing value
• What is the meaning of an exponential increase?

  Rapid growth.
• Explain how cell division is used in uni-celluar organisms.

  Asexual reproduction.
• What is the greenhouse effect?

  The process of trapping heat into the Earth's surface due to the greater transparency of the atmosphere to visible radiation from the sun.
• What is the meaning of mitigate?


  To reduce or lessen the severity, intensity, or impact of something.
• Photosynthesis takes place inside the chloroplasts that are found in plants and algae. The reaction is endothermic, meaning that it requires energy. The source of this energy is sunlight, which is trapped in the chloroplasts by the chemical, chlorophyll.