Answer:
Mitochondria and chloroplasts are much larger than prokaryotic cells.
Explanation:
According to the Endosymbiotic theory, all the components of eukaryotic cells were once individual prokaryotic cells which were able to function on their own.
The mitochondria was independent enough to perform aerobic respiration and produce energy and the chloroplasts were able to independently convert the energy from the Sun to the chemical energy through the process of photosynthesis.
Later, these cells were engulfed by a single cell and these prokaryotes combined to form a eukaryote that was capable of performing all the functions that the independent cells could.
So, the mitochondria and chloroplasts were able to reproduce on their own, had their own ribosomes and had DNA resembling that of bacteria as they were prokaryotic in nature.
However, mitochondria and chloroplasts could not be larger than the prokaryotic cells to support the endosymbiotic theory.
This is because in order to establish a relationship between the bacteria and the mitochondria and chloroplasts, and for these organelles to have developed from bacteria as their ancestors, they must have sizes comparable to bacteria and other prokaryotes.
At the same time, size in itself is not enough evidence to support origin of these organelles from the bacteria.
Answer:
Outside factors are not always constant meaning that there is little way to control them.
Explanation:
Agents that paralyze skeletal muscle by simple competitive inhibition of acetylcholine at muscle receptor sites are called?
a. nondepolarizing
b. depolarizing
c. antagonizing
d. repolarizing
Answer:
a. nondepolarizing
Explanation:
As the nerve impulse arrives, the synaptic end bulbs of the motor neurons release acetylcholine in the synapse. Acetylcholine binds to its receptors present at the motor endplate. This results in the opening of an ion channel in the ACh receptor to allow the movement of the Na+ into the cell. This makes the inside of the muscle fiber more positively charged, that is, depolarized.
Depolarization triggers a muscle action potential. Drugs or chemicals that paralyze skeletal muscle by competitive inhibition of acetylcholine at muscle receptor sites are called non-depolarizing as they do not allow the acetylcholine to facilitate the depolarization of the muscle fiber.
Answer: position of the carbonyl carbon
Explanation:
In the linear structure of sugars having an aldehyde group, are called aldoses, and sugars having a keto group are called ketoses.
Like adehydes H-C=O the carbonyl carbon is the first/last in the chain it is bounded to Hydrogen, double bounded to oxygen and a single bond to the chain. An aldose linear sugar like D-glucose have the carbonyl carbon as it first carbon.
But ketones R-COR the carbonyl carbon is in between the chain, it is bounded to two carbons on both sides. Like D-fructose the keto carbon is the second carbon.
In a open ring structure the 1st carbon, adehyde group is condensed with the hydroxy group (OH) of the 5th carbon forming a ring. The first carbon is now bound to the chain, Hydrogen, OH and oxygen which forms the ring.
In the keto open ring structure of D-fructose, the second carbon(keto group) is condensed with the OH of the 5th carbon
Answer:
a & c.
Explanation:
small local populations depend on a specific food source. If the food source is depleted because of the existing populus, chances are, there will be no reproduction. If the populus, does not look beyond their boundaries for food, the species will die.