B1 Science Flashcards
Osmosis
a process by which molecules/atom of a solvent/solution tend to pass through a permeable/partially permeable membrane from a less concentrated/more concentrated solution into a less concentrated/more concentrated one.
Digestion
Digestion breaks down large food molecules into
smaller molecules such as glucose, amino acids and
fatty acids that can be easily absorbed.
Diffusion
The particles go from high to low concentration.
Diffusion - Photosynthesis
Photosynthesis uses diffusion by taking sunlight and c02 and transferring it into usable energy. It makes this energy so it can grow bigger and stronger throughout the plants life. The plants use carbon dioxide to diffuse in and diffuses out the oxygen.
Diffusion - Digestive system
The digestive system has a large surface area as well therefore the most amount of energy can be taken in and used for working the body. The energy is then diffused into the blood stream to give it energy to grow and move around every dya.
Rate of diffusion
Concentration Gradient increased - makes diffusion faster,
Having a large surface area and being able to be thin for short distances.
Diffusion - lungs
Diffusion of the lungs occurs when alveoli diffuses in oxygen and carbon dioxide goes out. Alveoli have adapted to have a large surface area which helps to diffuse the largest amount of oxygen as possible. The energy crated from the lungs diffuses through the alveoli into the blood stream to give it the energy it needs.
Osmosis - water molecules
Water moves by osmosis from a dilute solution to the more concentrated solution (less water)
Osmosis in animal cells
Animal cells placed in a concentrated solution will shrink as water goes out however when placed in a dilute or still solution they will blow up and this will be called lysis
Osmosis - Animal cells - crenation
Crenation is when the animal cell shrinks in size until it can not shrink no more.
Osmosis - Animal cells - Lysis
Lysis is when an animal cell increases in size so much that it eventually blows up after becoming too big.
Osmosis - Plant Cell
In a concentrated solution a plant cell will get smaller and get larger when placed in a dilute solution
Plasmolysis
Plasmolysis is where the cell wall stays the same size however the cytoplasm shrinks inside the cell wall.
Active Transport
Molecules going From a low to high against the concentration gradient. Active transport is when the ions or water moves from low to high concentrations.
Magnification
Magnification
To work out magnification you need to do the equation.
Magnification= size of image
—————-
Size of real object
Microscopes
Microscopes can make things look alot bigger than they really are and it is the resolving power of a microscope that affects how much detail is shown.
Light Microscopes
Light microscopes have a resolving power of around 200nm
Electron Microscopes
electron microscope has a resolving power of 0.2nm
Animal Cell
The main parts of an animal cell is the nucleus, cytoplasm, cell membrane, mitochondria and ribosomes.
Cytoplasm
Cytoplasm is a liquid gel in which the organelles are suspended
Nucleus
A nucleus controlls all activities of the cell and is surrounded by nuclear membrane.
Mitochondria
Mitochondria are structures in the cytoplasm where respiration takes place.
Ribosomes
Ribosomes are where protein synthesis takes place.
Order Of Magnitude
Orders of magnitude are used to approximate comparisons between numbers or objects. If one number is 10x bigger than the other then the order of magnitude is bigger.
When cells become specialised they…
When cells become specialised they are better at what they have to do. For example a specialised nerve cell does a better job at the nerves.
Nerve Cells
The nerve cell shown in the diagram is specialised to carry nerve impulses from one place to another. These nerve cells can be up to 25 metres long!
Sperm Cell
sperm cell, they are specialised to contain genetic information from the male parent.
Striated muscle cell
a striated muscle cell and is specialised to contract and relax.
Phloem Cells
Phloem cells are specialised to transport tissue that carries food made by photosynthesis around the plants body. They make the food usable and help the plant to grow.
Root hair cell
root hair cell, these are adapted to increase surface area for water to move easier, they have a permanent vacuole to speed up water by osmosis and have many mitochondria for mineral transport.
Photosynthesis cell
Photosynthesis cells are cells that contain specialised green structures called chloroplasts, these trap light needed for photosynthesis. They are positioned in continuous layers and have a large permanent vacuole inside them.
Eukaryotic Cell
Eukaryotic cells are those from plants or animals. They all have a cell membrane,cytoplasm and genetic material enclosed in the nucleus.
Prokaryote cell
A prokaryote is a bacteria or single celled living organisms. They are so small that they can not be seen with a naked eye.
Chloroplast
Chloroplasts are found in all the green bits of the plant and this is because they contain chlorophyll, chlorophyll absorbs sunlight which can be used as energy.
Vacuole cell
A permanent Vacuole is the space in the cytoplasm filled with cell sap. It gives support to the plant.
Turgid
Turgid a plant cell with too dilute solution
Alveoli
They are very thin – only one cell thick.
They are covered by a network of fine capillaries,
enabling gases to pass almost directly between
the lungs and bloodstream.
They are moist, encouraging gas molecules to
easily dissolve.
They have a large combined surface area,
allowing large amounts of gases to be
exchanged with each breath.
Cross section through an alveolus
Alveoli are the tiny air sacs at the end of the
bronchioles, in which gas exchange occurs.
Breathing
Oxygen in inhaled air diffuses
through the lungs and into the
bloodstream. The oxygen is
then transported throughout
the body.
Carbon dioxide is the waste gas produced by
respiration. Carbon dioxide diffuses from body tissues
into the bloodstream and is exhaled via the lungs.
Villi
These are exactly the same as the villi, except a lot smaller.
Surface area : volume ration
As objects become bigger this ratio will get smaller
Xylem Cells
This is the cell in which active transport carries water and minerals up the plant.
Relative sizes
This tells us how big things are compared to another thing
To calculate magnification
You calculate magnification of eye piece by magnification of objective lens.
Synapse
Of a nerve cell is used to transmit impulses
Isotonic
If concentration of solutes is same as internal concentration then its isotonic.
Hypertonic
If the concentration of the solute in the solution outside the cell is higher than inside then it is hypertonic to the cell.
Hypotonic
If the concentration of solutes in the solution outside the cell is lower then inside cell is hypotonic.
