Answer:
Channel proteins form hydrophilic channels to passively transport substances down the concentration gradient.
Carrier proteins bind to substances to transport them actively against the concentration gradient. They do not form channels.
Explanation:
Channel proteins are the membrane proteins that serve in transport of small polar molecules and/or ions by making a hydrophilic pore across the membrane. These molecules diffusion through the pore and exhibit facilitated diffusion.
Carrier proteins are the membrane proteins that transport the substances across the membrane by binding to them. They do not form the hydrophilic channels. Carrier proteins serve in the active transport of molecules against the concentration gradient.
Oral ingestion or swallowing is the
administration method that takes the longest time for the drug to reach the
brain. When using this method, the drug is swallowed through the mouth, moves to
the stomach and then into the bloodstream before it can be transported to the
brain. This means that it takes longer for a swallowed drug to start functioning
than it does with other methods of administration such as injecting.
Answer:
A. is repeated many times to ensure that the results are accurate
Explanation:
A controlled experiment is repeated many times to ensure that the results are accurate
Answer:
chemical change.
Explanation:
There are two types of changes in matter: physical change and chemical change.
physical change- it is a change in matter that alters only its physical properties or its physical appearance. This type of change is reversible. For example- freezing of water, the water turns into solid ice and it can be reversed by melting the ice.
chemical change- it is a change in matter that alter its chemical and thus its physical properties. Most chemical changes are irreversible. for example- burning of paper, results in black soot and ashes- Thus changing both physical and chemical properties.
