Download Cell Wall

Biology
Absorption:
Movement of the products of digestion from the small intestine into blood
Active transport:
A process requiring energy in which molecules are moved from areas of low concentration to areas
of high concentration
Alimentary Canal:
The tube that runs from mouth to anus
Benedict’s test:
The test for reducing sugars, e.g. glucose
Carbohydrate:
food substance that provides energy, e.g starch and glucose. Composed of carbon, hydrogen and
oxygen.
Cellulose:
a complex carbohydrate that makes up the cell walls of plant cells.
Cell membrane:
the boundary of the cell which controls the materials that pass into and out of it.
Cell Wall:
the outer layer of a plant, made of cellulose which supports the cell and gives it shape.
Denaturation:
Breaking bonds in an enzyme, stopping it from working
Digestion:
The breakdown of large insoluble molecules into smaller soluble ones
Diffusion:
Movement of molecules from areas of high concentration to areas of low concentration
Disaccharide:
Two molecules (monomers) of sugar joined together
Egestion:
The removal of undigested products from the body
Enzyme:
A biological catalyst (something that speeds up the rate of chemical reactions without being used up)
Excretion:
The removal of metabolic waste products from the body
Flaccid:
a plant cell that has lost water by osmosis so that the cell contents no longer push outwards against
the cell wall.
Gene:
a length of DNA, found on a chromosome that codes for a particular characteristic.
Guard Cells:
Cells which control the opening and closing of the stomata
Hypertonic:
A solution with a lower concentration of water (water potential) than the cell
Hypotonic:
A solution with a higher concentration of water (water potential) than the cell
Ingestion:
the process of taking in food
Isotonic:
A solution with the same concentration of water (water potential) as the cell
Large intestine:
the final parts of the alimentary canal that absorb water and store faeces.
Lipase:
the enzyme that digests fats to fatty acids and glycerol.
Magnesium:
Used to make chlorophyll
Monosaccharide:
A single molecule (a monomer) of sugar
Mucus:
a slimy, sticky substance that traps dust s and some microbes in the air pathways.
Nucleus:
the part of the cell that contains genetic information in the form of chromosomes. The nucleus
controls the activities of the cell.
Nitrate:
Used to make proteins. Chemical fertilisers often supply nitrate ions needed for healthy plant
growth.
Oesophagus:
the muscular tube connecting the mouth with the stomach. Food passes down the oesophagus by a
wave of muscular contraction called peristalsis.
Osmosis:
The movement of water molecules from areas of high concentration to areas of low concentration
across a partially permeable membrane
Palisade mesophyll:
Tissue in the leaves that contain many chloroplasts and are the main site of photosynthesis
Peristalsis:
Waves of muscle contraction that move food through the alimentary canal
Phloem:
Plant tissue that transports sugars and amino acids
Phosphate:
Used in photosynthesis and respiration
Photosynthesis:
6CO2 + 6H2O → C6H12O6 + 6O2
Plasmolyzed:
A plant cell that has lost so much water that the cell membrane has shrunk away from the cell wall
Polysaccharide:
Many molecules (monomers) of sugar joined together
Progesterone:
a hormone secreted by the ovaries and by the placenta that maintains the lining of the uterus
during the second half of the menstrual cycle and during pregnancy.
Protease:
an enzyme that breaks down proteins to amino acids
Proteins:
made up of amino acids. Needed for growth and repair of tissues in the body. They contain the
elements carbon, hydrogen, oxygen, nitrogen and sulphur.
Rectum:
the last part of the large intestine where faeces are stored before passing out the anus.
Respiration:
A chemical reaction that releases energy from food
Respiratory system:
An organ system whose purpose is to allow for gas exchange
Root hairs:
Specialised cells in a root that provide a large surface area for the absorption of water and mineral
salts.
Stomata:
A hole in the epidermis of the leaves that allows for gas exchange to occur
Substrate:
The molecule which an enzyme works on
Translocation:
The movement of sucrose and amino acids in the phloem
Transpiration:
Loss of water via evaporation and diffusion of water vapour out of the leaves
Tropism:
a growth response by part of a plant to a stimulus, e.g light or gravity
Turgid:
A plant cell that is full of water
Vacuole:
fluid-filled sac containing cell sap present in most plant cells.
Vein:
A blood vessel through which blood travels towards the heart.
Ventilation:
The movement of air in and out of the lungs
Villus (Villi):
tiny hair-like projection from the wall of the small intestine. Villi increase the surface area of the
small intestine for absorption of digested food.
Xylem:
Plant tissue that transports water and minerals from the roots to the leaves / flowers
Zygote:
A fertilised egg
Ventilation:
The movement of air in and out of the lungs