Biology Paper 1

• What do both animal and plant cells have?

  • nucleus
  • cell membrane
  • cytoplasm
  • mitochondria
  • ribosomes
• what are the features of a bacterial cell?

  • cell wall
  • cell membrane
  • cytoplasm
  • plasmids
  • free DNA
• What does the nucleus do?

  Contain genetic material and control the cell
• What happens in the cytoplasm?

  Chemical reactions
• What does the mitochondria do?

  Create energy for the cell through respiration (aerobic respiration)
• What happens in the ribosomes?


  Protein synthesis
• What happens in the chloroplasts?

  Photosynthesis
• What are plasmids?


  Small rings of DNA
• What cells are specialised?

  • Sperm cells
  • Nerve cells
  • Muscle cells
  • Root hair cells
  • Xylem cells
  • Phloem cells
• How are sperm cells adapted to function properly?

  • many mitochondria
  • streamlined point head
  • digestive enzymes in the top of the head
• How are nerve cells adapted to function properly?

  • long axon - impulses are carried long distances
  • lots of extensions - form connections with other cells
• How are muscle cells adapted to function properly?

  • mitochondria - provide energy for contraction and respiration
• How are root hair cells adapted to function properly?

  • large surface area - more water can move in
  • permanent vacuole - water moves in quickly
• What is differentiation?


  The process by which a cell changes to become specialised
• What is mitosis?


  a cell dividing into two identical daughter cells
• Why does cell division happen?

  To repair or replace damaged cells
• What is the formula for magnification?

  Actual size x Magnification = Image size (IAM)
• What is a gene?

  A short section of DNA that controls a characteristic
• How many chromosomes are there in each cell?

  46
• How many chromosomes are in a single sex cell?

  23
• What are the stages of mitosis?

  • Interphase - the cell grows and DNA is replicated
  • Prophase - the DNA becomes more visible
  • Metaphase - Chromosomes and their copies line up in the middle of the cell
  • Anaphase - Chromosomes and their copies are pulled apart
  • Telophase - new cell membranes form
  • Cytokinesis - two daughter cells are finally formed
• Why does mitosis take place?

  • to replace damaged cells
  • asexual reproduction
• What is a stem cell?

  An undifferentiated cell which goes under cell division to produce identical copies
• What are the types of stem cells?

  • Embryonic stem cells
  • Adult stem cells
  • Meristems in plants
• What is an embryonic stem cell?

  Cell formed of a zygote (foetus) that can be cloned and diferentiated into any other type of cell
• What is an adult stem cell?

  A cell found in bone marrow that can form many types of cells including blood cells
• What is a meristem cell?


  A cell found in plants roots and shoot tips that can differentiate into any type of plant
• What is therapeutic cloning?

  An embryo being produced with the same genes as a patient
• What can therapeutic cloning be used for?

  The embryo can be grown to form the cells that a patient needs e.g. tissue or organs
• What are the benefits of research with stem cells?

  • Can be used to replace damaged or diseased body parts
  • Unwanted embryos from fertility clinics can be put to use
• What are the disadvantages to research with stem cells?

  • hard to control them to function properly
  • could destroy the embryo trying to remove cells
  • interferes with natural process of reproduction
  • takes lots of money and time
• What is diffusion?


  The movement of particles from an area of high to low concentration
• Where does diffusion take place in the body?

  • the lungs
  • the small intestine
• What are the factors that affect the rate of diffusion?

  • concentration gradient
  • temperature
  • light intensity
  • surface area
• What is osmosis?


  The movement of water particles from less concentrated solution to a more concentrated one through a partially permeable membrane
• What is active transport?

  movement of particles from low concentration to high concentration against their own concentration gradient
• What fluid is found inside a plant cell's permanent vacuole?

  cell sap
• What is the order of the digestive system?
• What is the order of the digestive system?

  • Mouth
  • Oesophagus,
  • Liver
  • Stomach
  • Pancreas
  • Gall bladder
  • Small intestine
  • Large intestine
  • Rectum
• What does the stomach do?

  Produce digestive enzymes that break down food while we chew