Answer:
The duplication of a cluster of four Hox genes is equally likely as the duplication of a single Hox gene.
Explanation:
This comes from the definition of the parsimony principle, which is the action of choosing the simplest scientific explanation fitting the given evidence, meaning that all other elements are equal when evaluating the hypothesis. In biology the best hypothesis is the one that requires the fewest evolutionary changes.
Since three independent duplications of an individual Hox gene is in evolutionary terms, more complex than a single duplication or a cluster, then that hypothesis would be the most parsimonious.
Answer:
Blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium.
Explanation:
The correct answer is: the wail of a loud car alarm.
Sensory adaptation is a term that refers to the changes that stimuli can trigger on the sensory receptors. The process involves changes in the receptors' sensitivity and it is believed that all of the senses exhibit this adaptation. In particular, the sense of touch can quickly adapt to hot and cold stimulation, but not when the stimulus is extremely intense (such as too hot or too cold). Also, our olfactory sense presents the characteristic of odour fatigue. A prolonged exposure to a specific smell leads to a temporary inability to sense this smell and this is a type of sensory adaptation. Finally,
our hearing undergoes a sensory adaptation as well, but not when it comes to sudden, unexpected and instantaneous loud noises. That is why the wail of a loud car alarm will be the least likely to cause sensory adaptation.
Answer:
yes
Explanation:
because the only thing that is changing is the number of cells, mitosis causes cells to split and multiply forming organisms
<span>The formation of the fertilization envelope (slow-block to polyspermy) requires an increase in the availability of </span>calcium ions.
Slow-block to polyspermy is also called cortical reaction. In this reaction, the sperm will be permanently blocked by cortical granules. The release of calcium ion will trigger this reaction.