When a muscle receives nerve signal contracts and pulls on a tendon.
Answer:
Capacity.
Explanation:
If there are too many people first of all space would run out first then food and water its hard sometimes to consider factors like this so you have to make sure that your reasoning with your point.
Answer:
<u>Pro:</u>
May hold answers to cure various diseases including Alzheimer's and Parkinson's - these may be answers to various diseases that are not able to cure.
Requires a small number of cells because of the fast replication rate - these are able to produce a high amount of cells in the lab as they are able to replicate faster.
Medical benefits such as regenerating organ tissue and therapeutic cell cloning
<u>cons:</u>
ethical controversy over use of stem cells from lab fertilized human egg - there is an ethical controversy around the use of lab fertilized human egg
unproven treatments often come with high rejection rates - these researches provide uncertain results and not tested and easily affected so the rate of rejection is high
The cost can be prohibited for many patients - these require high cost and can not be in the budget of every patient.
Natural selection leads to increases in the mean fitness of populations and so will reduce the frequency of disease-associated alleles, but other evolutionary processes, such as mutation and gene flow, may introduce or increase the frequency of these deleterious alleles.
