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.
Answer:
C
Explanation:
Due to technology being ubiquitous, more and more gadgets that are produced are consuming more and more energy. This means that there is a need for cheap energy. Currently, cheaper sources of energy are non-renewable such as coal and crude oil. These pollute the environment causing climate change.
Answer:
Should be D. Breathable gases
Explanation:
The carrying capacity of an environment is the maximum population size of a biological species that can be sustained by that specific environment, and abiotic factors are non-living chemical and physical parts of the environment that affect living organisms and the functioning of ecosystems.
Answer:
A
Explanation:
<em>The correct option would be </em><em>A.</em>
<u>The presence of ammonia in the atmosphere of primitive earth provided the nitrogen found in the amine groups of amino acid and the nitrogenous bases in DNA. This has been proven through the simulation experiment of the primitive earth's atmosphere by Stanley Miller and Harold Urey.</u>
The water in the primitive atmosphere was formed from the condensation of water vapour from volcanoes that were characterics of the earth's environment while oxygen in itself is not needed for photosynthesis but a by-product of it.
