Biology paper 1

• Where are ciliated epithelial cells found ?

  On the surface of organs
• Give two functions of an egg cell

  To carry the female DNA and to provide nutrients to the embryo in the early stages
• Why do sperm cells contain a large number of mitochondria ?

  To provide the energy needed to swim to the egg
• What is mitosis ? What is it used for ?

  The stage of the cell cycle when the cell divides, organisms use mitosis to grow or replace cells that have been damaged, or to reproduce
• Name the four stages of the cell cycle that are part of mitosis

  Prophase, metaphase, anaphase and telophase
• What happens during cytokinesis ?

  The cytoplasm and cell membrane divide to form two separate cells
• Name the two methods that plants use to grow

  Cell division and cell elongation
• What is an embryonic stem cell ?

  An undifferentiated cell found in early human embryos, which has the potential to divide and produce any kind of cell at all
• Where can stem cells be found in an adult human ? What do they do ?

  Bone marrow, they are used to replace damaged cells, such as blood or skin cells
• What type of plant tissue contains stem cells ?

  Meristem tissue
• What is a synapse ?

  A connection between two neurones
• How are nerve signals transferred across a synapse ?

  Neurotransmitters diffuse across the synapse and set off a new electrical impulse in the next neurone
• True or false ? People with long-sightedness are unable to focus on distant objects

  False
• Give four defects of the eye that cause vision problems

  Long sightedness, short sightedness, colour blindness and cataracts
• What is a mutation ?

  A rare, random change in an organisms DNA base sequence
• Describe what is meant by a genetic variant

  A different version of a gene, caused by a mutation within the gene
• True or false ? Amino acids are joined together during transcription

  False
• Which stage of protein synthesis involves RNA polymerase ?

  Transcription
• How many pairs of chromosomes are involved in determining sex in humans ?

  One pair
• What chromosome does each sperm cell contain ?

  Either X or Y
• True or false ? Communicable diseases can be spread between people

  True
• Give two examples of non-communicable diseases

  Cancer and heart disease
• Bacteria, viruses and fungi are examples of types of pathogens, give one other example of a type of pathogen

  Protists
• True or false ? The pathogen that causes Ebola is a bacterium

  False
• Which type of pathogen causes malaria ?

  A protist
• What cells in the body are killed by HIV ?

  White blood cells
• Give the equation used to calculate the area of a circle

  Area = 3.14 r^2
• Is a plant cell a prokaryotic cell or a eukaryotic cell ?

  A eukaryotic cell
• In which subcellular structures do most of the reactions take place ?

  Mitochondria
• Which subcellular structure maintains the internal pressure in a plant cell ?

  Vacuole
• What is the purpose of the fine adjustment knob on a light microscope ?

  It’s used to focus the lens until a clear image of what’s on the slide appears
• True or false ? Electron microscopes have a smaller magnification than light microscopes, but they have a higher resolution than light microscopes

  False
• Is a picometre smaller or larger than a nanometre ?

  Smaller
• A student knows the eyepiece lens and objective lens magnification of their microscope. What formula should they use to calculate the microscopes total magnification ?

  Total magnification = eyepiece lens magnification x objective lens magnification
• How do enzymes affect the rate of reaction ?

  Enzymes increase the rate of reaction
• What is an active site of an enzyme ?

  The part of the enzyme which joins on to its substrate to catalyse the reaction
• True or false ? Enzymes have a high specificity for their substrate

  True
• True or false ? PH is the dependant variable in an experiment investigating how PH affects enzyme activity

  False
• In an experiment investigating how PH affects amylase activity, what would you use to test for the presence of starch ?

  Iodine solution
• Which type of molecule are proteins broken down into ?

  Proteins are broken down into amino acids