Cause mammals are the only species that are well developed before birth unlike marsupial and monotremes
Answer:
d. more permeable to sodium ions.
Explanation:
The binding of Acetylcholine with the receptors at motor end plate facilitate membrane permeability to sodium ions therefore opening of voltage gated channels for sodium ions.
Sodium ions diffused into the synapse of post synaptic neuron at the neuromuscular junction.
If the stimulus is up to threshold levels; more chemical(neurotransmitter) gated sodium channels opens, and sodium ions move into the synapse to depolarize the membrane with reversal of charges to generate action potential.
The continuous binding of Acetycholine , leads to permanent opening of sodium ions,and over excitation from depolarization. Acetycholinesterase enzymes breakdown Acetycholine to choline and Acetyl Co -A. These are recycle back to Acetycholiine
Answer:
the cell would not be able to produce vacuoles
Answer:B) progress towards the replication fork.
Explanation:
Replication fork is a point on the parental DNA where the DNA is being unwound and separated; and the separated strands are being replicated. Synthesis of a new DNA strand occurs in a 5' -> 3' direction, as the DNA strand serving as the template is read from its 3' -> 5' direction. During replication, two strands of DNA are synthesized: The leading strand is synthesized continuously in the same direction as the replication fork movement while the lagging strand is synthesized discontinuously in the direction opposite to the direction of fork movement, that is, towards the replication fork. The lagging strand is synthesized in short fragments known as Okazaki fragments.