biology paper one

• what is osmosis?


  Osmosis is the diffusion of water from a high to a low concentration using partially permeable membrane.
• what does homeostasis do?

  homeostasis makes sure our body has the correct levels of: glucose, water, carbon dioxide, oxygen, temperature.
• what is the definition of homeostasis?

  homeostasis involves maintaining a constant environment in the body
• what is the natural body temperature?

  37 degrees celcius
• what is the first step of meiosis?

  Before a cell divides its genetic info is duplicated, creating a chromosome that has two identical chromatids. This is DNA replication.
• what are the two types of cells?

  Eukaryotic and Prokaryotic
• What do Eukaryotic cells consist of?

  Plant cells, and Animal cells
• What do Prokaryotic cells consist of?

  Bacteria cells
• What equation do you use too work out magnification when using a microscope?

  Magnification= image size ÷ actual size
• What is a stem cell?

  A stem cell is a cell that can change into different types of specialised cell but hasnt yet
• Name types of specialised cells.

  Nerve cells, sperm cells, egg cells, brain cells, muscle cells, red blood cells and root hair cells.
• What is a specialised cell?

  A specialised cell is a cell that is adapted for a function, Eg sperm cells have a flagella too swim to the egg cell.
• What is mitosis?

  Mitosis describes the process from one cell dividing into two daughter cells. An example of this is roots of a plant growing.
• What is diffusion?

  Diffusion is the net (general) movement of particles from a high concentration to a low concentration.
• What is active transport?

  Active transport is the net movement of particles from a low concentration to a high concentration against a gradient concentration (high too low)
• What do cells make up into?

  Tissues
• What do tissues make up into?

  Organs
• What do organs make up into?

  Organs (stomachs, intestines...) make up into Organ Systems (digestive system)
• What are the three types of enzymes?

  Lipase, Protease and Carbohydrase
• What are there lots of in the digestive system?

  There are lots of enzymes.
• What is the lock and key?

  When each substrate (key) fits into one specific active site (lock)

  
• Where does the digestive sytem start?

  It starts in the mouth and moves down through the esophagus to your stomach.
• After the stomach, where does your food go too?

  Small intestine then into the large intestine.
• After the large intestine, where does your food go in the digestive system?

  The rectum where waste food is stored before excretion (pooing)
• What is the test for starch?

  The test for starch is the iodine test when you add a few drops too a food sample, which turns the starch solution from orange to blue-black in colour.
• What is the test for sugars?

  Benedict's test. You add one drops of benedict solution to a food sample, then heat it gently, if sugar is present the benedict solution will change from blue to red colour.
• What is the test for proteins?


  Add a few drops of biuret solution to a food sample, once shaken if protein is present the biuret solution will go from blue too purple.
• which way round are the left and right in the heart?

  the left side for you is the right side of the heart and the right side for you is left side of the heart.
• What are the three main blood vessels involved in the circulatory system (heart)?

  Artery, veins and capillaries.
• What are the properties of an artery and what does it do?

  Arteries carry oxygenated blood away from the heart. They have thick walls and carries blood at high pressures as it has a small lumen.

  
• What are the properties of a vein and what does it do?

  Veins carry deoxygenated blood, has valves to prevent backflow, thinner walls than arteries. Veins carry blood back too the heart through the vena cava into the right atrium.
• What are the properties of capillaries and what do they do?

  Capillaries have thin walls. They preform gas exchange in the body. They have permeable walls for easy diffusion
• What is plant organisation?

  Plant organisation involves the structure of a leaf.

  
• What is a xylem?


  Plant tissue that transports water and nutrients from the roots to the rest of the plant.
• what is a phloem?

  transporting foods up and down the plant through the phloem.
• what is a communicable disease?

  A disease that can be transmitted from one person to another.
• What are the 4 pathogen types that can be communicable?

  Bacteria, viruses, fungi, parasites.
• what is a pathogen?

  A pathogen is a microorganism that causes disease in plants or animals (animals also include humans)
• How can the 4 pathogens be spread?


  Air, direct contact(touch)and water.
• Our body can prevent disease in many different ways, What is the first line of defence our body has?


  Physical barriers, for exmaple skin and hair.