Biology Paper 1

• What is the focus of the AQA GCSE Biology paper 1?

  Cells, organization, infection, and bioenergetics
• What is the difference between eukaryotic and prokaryotic cells?

  Eukaryotic cells have a nucleus; prokaryotic do not
• What structures can be seen with a light microscope?

  Cells and possibly the nucleus
• What advantage do electron microscopes have over light microscopes?

  They allow us to see finer details
• How can you calculate the actual size of a cell?

  Divide image size by magnification
• What is the function of the cell membrane?

  It keeps everything inside the cell
• What is the composition of the plant cell wall?

  Made of cellulose
• What is the role of mitochondria in a cell?

  Where respiration takes place
• What do ribosomes do?

  Assemble proteins
• What is the function of chloroplasts in plant cells?

  Photosynthesis occurs here
• What is a permanent vacuole in plant cells used for?

  Storing sap
• How do bacteria multiply?

  By binary fission
• What technique is used to produce a culture on agar?

  Aseptic technique
• Why do we lift the lid of the dish towards a flame during culturing?

  To move microbes away and destroy them
• What temperature do we incubate bacterial cultures?

  25°C
• How do you calculate the area of a circle?

  $A =$$\frac{\pi d^2}{4}$
• What is the genetic material in eukaryotic cell nuclei?

  DNA stored in chromosomes
• How many pairs of chromosomes do humans have?

  23 pairs
• What are gametes in terms of chromosome number?

  They have 23 chromosomes
• What is mitosis used for?

  Growth and repair of cells
• What happens to genetic material during mitosis?

  It is duplicated and divided
• What are stem cells?

  Cells that haven't specialized yet
• Where are stem cells found in humans?

  In embryos and bone marrow
• How can stem cells be used in medicine?

  To combat conditions like diabetes
• What is diffusion?

  Movement from high to low concentration
• What is osmosis specifically?

  Diffusion of water across a membrane
• How can the rate of diffusion be increased?

  By increasing concentration difference
• What is the practical method for osmosis using potatoes?

  Weigh, place in sugar solutions, and reweigh
• How do you calculate percentage change in mass?

  $\frac{final mass - initial mass}{initial mass} \times 100$
• What is active transport?

  Movement against a concentration gradient using energy
• What do tissues form?

  Organs
• What is an organ system?

  A group of organs working together
• What is the role of bile?

  Neutralizes stomach acid and emulsifies fats
• What are enzymes?

  Biological catalysts
• What does amylase do?

  Breaks down starch into glucose
• What is the lock and key principle in enzymes?

  Substrate fits into the enzyme's active site
• What happens to enzymes at high temperatures?

  They can denature and lose function
• How do you determine the optimum temperature for enzyme activity?

  By timing starch breakdown at different temperatures
• What color does iodine turn in the presence of starch?

  Black
• What is the difference between breathing and respiration?

  Breathing provides oxygen for respiration