Each sieve tube element is normally associated with one or more nucleated companion cells, to which they are connected by plasnodesmata (channels between the cells). Each companion cell is derived from the same mother cell as its associated sieve tube member. Sieve tube members have no cell nucleus, ribosomes, or vacues. Thus, they depend on companion cells to provide proteins, ATP, and signalling molecules
MRNA is always single stranded
Answer:
protein
Explanation:
see attached for human skill
Energy (caloric) value of foods is indicated by calories, which measure the amount of heat that the food releases in the metabolic process. In physiology, it is determined by the energy balance of the organism, ie the heat exchange between the organism and the external environment.
Calories of nutrients:
1 g of protein = 4 kcal (kilocalories)
1 g of fat = 9 kcal
1 g of carbohydrates = 4 kcal
1 g of alcohol = 7 kcal
1 g of organic acid = 3 kcal
According to the table above, we can calculate required value:
29x4 + 6x4 + 1x9= 149 kcal/g
The main function of the PNS is to connect the CNS to the limbs and organs. The PNS sends information to the CNS as quickly as possible.
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