B1 Flashcards
What is active transport
The movement of dissolved molecules in or out of a cell through the cell membrane. Area of low to high concentrstion. Against the concentrstion gradient. Using Energy released from respiration.
Label a plant cell
Nucleus
Chloroplasts
Cytoplasm
Permanent vacuole
Cell wall
Mitochondrion
Cell membraine
Ribosomes.
Label an animal cell
Nucleus
Ribosomes
Mitochondria
Cytoplasm
Cell membrane.
Function of the nucleus
Stores DNA and co ordinates cells activities.
Function of the chloroplasts ( plant cell )
Produce energy through photosynthesis. Responsible for biosynthesis of active compounds ( amino acids) ( lipids) etc.
Function of the cell wall ( plant cell )
Provides protection against osmotic stress.
Function of the cytoplasm
Responsible for holding parts of a cell and protecting them from damage.
Function of the Permanent vacuole ( plant cell )
Filled with cell sap to help keep the cell turgid.
Function of the mitochondria
Generate chemical energy for biochemical reactions. Chemical energy stored in ATP.
Site of aerobic cellular respiration.
What does ATP stand for.
Adenosine triphosphate.
Function of the cell membrane
Semipermeable lipid bilayer. Regulates transport in and out the cell.
Function of ribosomes
Made of RNA and protien. The site of protein synthesis in the cell. Amino acids grow into long chains forming proteins.
What is osmosis
The diffusion of water through a partially permeable membrane. From a dilute to concentrated solution. ( High to low concentrstion of water ) down the concentrsion gradient.
Hypertonic ( osmosis )
A solution that is more concentrated than the cell contents.
Hypotonic ( osmosis )
A solution that is less concentrsted than the cell contents.
Isotonic ( osmosis )
A solution that is the same concentration as the cell contents.
Eukaryotic cells
Cells from eukaryotes. Have a cell membrane. Cytoplasm. And genetic material stored in a nucleus.
Prokaryotic cells
cytoplasm surrounded by a cell membrane, and a cell wall that does not contain cellulose. The genetic material is a DNA loop that is free in the cytoplasm and not enclosed by a nucleus. Sometimes there are one or more small rings of DNA called plasmids.
NO NUCLEUS.
partially permeable membrane
a membrane that allows only certain substances to pass through.
Phloem
The living transport tissue in plants that carries dissolved foods ( sugars ) around the plant.
Xylem
The non living transport tissue in plants that transports water from the roots into the leaves and shoots.
Plasmolysis
The state of plant cells when too much water is released from osmosis so the that the vacuole and cytoplasm shrink and the membrane pulls away from the cell.
Resolving power
A measure of the ability to distinquish between two seperate points that are very close together.
Sperm
The male sex cells or gametes that carry the genetic matierial from the male parent.
Stomata
Openings in the leaves of plants. Opened and closed by guard cells. Allowing gases to enter and leave the leafs.
How to work out magnification
Magnificstion = size of image / size of real object.
Whats the difference between magnificstion and resolution
Magnification is the ability to make small objects seem larger. Resolution is the ability to distinguish two objects from each other.
Compare and contrast light and electron microscope
light microscopes are used to study living cells and for regular use when relatively low magnification and resolution is enough. electron microscopes provide higher magnifications and higher resolution images but cannot be used to view living cells.
When might you use an electron microscope
to investigate the ultra structure of a wide range of biological specimens including microorganisms, cells, large molecules, metals.
Comparing cell by magnitude
Divide larger magnitude my smaller magnitude (also width / diameter )to work out the total amount of times bigger on cell is than the other.
Describe the function of muscle cells in the wall of the stomach
It squeezes the stomach walls together to help move partly digested food into the small bowel.
Suggest why the ribosomes cannot be seen through a light microscope.
The ribosomes are too small for the maximum magnificstion of s light microscope.
