Answer:
b. to amplify the signal
Explanation:
A multi-enzyme phosphorylation cascade is a series of signaling events where one enzyme phosphorylates to another, then this last enzyme acts to phosphorylate another protein and so successively, thereby triggering a chain reaction that leads to the phosphorylation of hundreds or even thousands of proteins. A multi-enzyme phosphorylation cascade is known to increase the number of activated (phosphorylated) proteins at each step of the signaling cascade. Phosphorylation is a posttranslational modification capable of activating proteins during long periods, thereby a phosphorylation cascade also enables the activation of multiple proteins before these proteins become inactive again.
 
        
             
        
        
        
Answer is A Sunlight because the grass are staying in the shade which they’re not getting sun light
        
             
        
        
        
Question 1 The world's population is spread very unevenly. Some spaces are empty or very sparsely populated: we speak of human deserts:
• Cold polar environments are the least populated regions: the ground, frozen permanently, prevents any form of agriculture, the very low temperatures make the habitat difficult.
• The hot or cold desert environments are also not busy: the lack of rain and the strong heat during the day limit the activities of men. The only exceptions are oases.
• The role of relief is more difficult to define. High temperate mountains like the Alps are generally sparsely populated but tropical chains like the Andes have a high population density. However, men have generally settled in the plains, in the valleys (along with the rivers) and on the coasts.
There are also other factors unrelated to land factors that influence population density such as job availability, or even historical factors.
Question 2: Birth rate:
The birth rate (sometimes called the crude birth rate) is the ratio of the annual number of births to the average total population for that year. When the population grows, the contact between people will be more permanent, and it will increase the marriage rate, and thus the birth rate. Age structure:The age structure is a mode of graphical representation of the structure (of age as well as of sex) of a population which constitutes a synthetic image of the past, present and future of the population.When a population resides for a long time in the same place (in favorable conditions, not raising the death rate and without moving), this will vary the age structure by observing an increase in the elderly population.
 
        
                    
             
        
        
        
Answer: Natural Causes and Human Activities 
Explanation:
The factors influencing kelp forest stability are diverse: kelp harvesting; grazing by fishes, sea urchins, and crustaceans; plant competition; storms; sedimentation; and pollution; global warming and the association with rising ocean temperatures. 
 
        
                    
             
        
        
        
Answer:The Food Chain: The answer has to do with trophic levels. As you probably know, the organisms at the base of the food chain are photosynthetic; plants on land and phytoplankton (algae) in the oceans. These organisms are called the producers, and they get their energy directly from sunlight and inorganic nutrients. The organisms that eat the producers are the primary consumers. They tend to be small in size and there are many of them. The primary consumers are herbivores (vegetarians). The organisms that eat the primary consumers are meat eaters (carnivores) and are called the secondary consumers. The secondary consumers tend to be larger and fewer in number. This continues on, all the way up to the top of the food chain. About 50% of the energy (possibly as much as 90%) in food is lost at each trophic level when an organism is eaten, so it is less efficient to be a higher order consumer than a primary consumer. Therefore, the energy transfer from one trophic level to the next, up the food chain, is like a pyramid; wider at the base and narrower at the top. Because of this inefficiency, there is only enough food for a few top level consumers, but there is lots of food for herbivores lower down on the food chain. There are fewer consumers than producers.
Land and aquatic energy pyramids
Trophic Level	Desert Biome	Grassland Biome	Pond Biome	Ocean Biome
Producer (Photosynthetic)	Cactus	Grass	Algae	Phytoplankton
Primary Consumer (Herbivore)	Butterfly	Grasshopper	Insect Larva	Zooplankton
Secondary Consumer (Carnivore)	Lizard	Mouse	Minnow	Fish
Tertiary Consumer (Carnivore)	Snake	Snake	Frog	Seal
Quaternary Consumer (Carnivore)	Roadrunner	Hawk	Raccoon	Shark
Food Web: At each trophic level, there may be many more species than indicated in the table above. Food webs can be very complex. Food availability may vary seasonally or by time of day. An organism like a mouse might play two roles, eating insects on occasion (making it a secondary consumer), but also dining directly on plants (making it a primary consumer). A food web of who eats who in the southwest American desert biome might look something like this:
Explanation: