cell structure and organization
this structure surrounds the cytoplasm in both plant and animal cells and controls what enters and leaves
what is a cell surface membrane?
The net movement of particles from a region of higher concentration to a region of lower concentration, down a concentration gradient.
what is diffusion?
Adding this brown solution to starch turns it blue-black.
what is iodine solution?
Most absorption of digested food takes place in this part of the alimentary canal.
what is the small intestine (ileum)?
This green pigment in chloroplasts absorbs light energy for photosynthesis.
what is chlorophyll?
plant cells, but not animal cells, have the rigid layer made of cellulose outside the cell surface membrane
what is the cell wall?
The net movement of water from a dilute solution to a concentrated solution across a partially permeable membrane.
what is osmosis?
When heated with glucose, Benedict’s solution forms a precipitate of this colour.
what is brick-red(orange-red)?
This enzyme in saliva breaks starch down into maltose.
what is amylase?
These tiny pores, mostly in the lower epidermis of a leaf, allow gases to enter and leave.
what are stomata?
muscle cells and sperm cells contain many of these organelles, the site of aerobic respiration
what are mitochondria?
A plant cell placed in a concentrated sugar solution loses water until the membrane pulls away from the cell wall. This is called this.
what is plasmolysis?
At high temperatures an enzyme loses its shape and stops working. This permanent change is called this.
what is denaturation?
These wave-like muscle contractions push food along the alimentary canal.
what is peristalsis?
This is the loss of water vapour from the leaves of a plant, mainly through the stomata.
what is transportation?
A micrograph shows a cell that is 60 mm long. Its actual length is 0.03 mm. This is the magnification.
what is x2000
Root hair cells take in nitrate ions from soil where they are scarcer than inside the cell. This process, which explains the many mitochondria in these cells, is called this.
what is active transport?
Only one substrate fits the active site of an enzyme because the shapes are complementary. This property is called this.
Bile helps fat digestion by breaking large fat droplets into smaller ones, increasing the surface area for lipase. This physical process is called this.
what is emulsification?
Nitrate ions absorbed by roots are used to make these molecules, and a shortage causes stunted growth.
what are amino acids (protein)?
In the fluid mosaic model, the bilayer is made of these molecules, whose hydrophilic heads face the watery surroundings and whose hydrophobic tails face inwards
what are phospholipids
Pure water has the highest possible water potential. This is its value
what is zero (0kPa)
A competitive inhibitor reduces enzyme activity by binding to this part of the enzyme, blocking the substrate.
what is active site?
In a villus, fatty acids and glycerol are absorbed into this lymph vessel rather than into the blood capillaries
what is lacteal?
Sucrose and amino acids are moved from leaves to roots and fruits through the phloem by this process.
what is transolcation?