Answer:
As insect nymphs grow larger, their exoskeleton becomes too tight and they must replace it. Once a nymph outgrows its exoskeleton it will go through a process called molting, in which it leaves the old “skin” or exoskeleton behind. The new “skin” will harden and become the new exoskeleton
Explanation:
Both. You can use it as singular or plural.
Answer:
Both A and C is the right
1 - A ground level plant develops curling tendrils that wrap around other objects so it can "climb".
This is a species changing over time as it was originally a ground level plant but began to climb higher.
2 - Over many generations.
This is because diversity takes time and has to be integrated through generations; for instance, marriage. In a family, it becomes more diverse after the next generation as each generation is likely to marry someone of another ethnicity and allow the family tree to become more diverse.
3 - Mutate or Survive
It depends on what it means by mutate - develop a mutation to make it adaptable? If that's the case, then mutations within the DNA would be a result of adaptation and increase survival. Otherwise, survive is the obvious answer as adaption allows for species to move around and live longer.
Hope this helps!
The Mitral valve which is also known as left atrioventricular prevents blood movement from left ventricle to left atrium.
Explanation:
- Human heart is four chambered.
- Two of these are receiving chambers known as atria and the other two are distributing chamber known as Ventricles.
- Atria are superior chambers and ventricles are inferior chambers.
- The heart has four valves broadly grouped as Atrioventricular valves and Semi lunar valves.
- Atrioventricular valves allows flow of blood from atria to ventricle. These are tricuspid valve and bicuspid valve.
- Semi-lunar valves allow blood to pass out of the heart. These include the pulmonary and aortic valves.
- The pulmonary valve allows blood to flow from right ventricle to the heart while aortic valve allows blood to flow from left ventricle to the Aorta.
- The Tricuspid valve located between the right atrium and right ventricle allows blood to flow from right atrium to the right ventricle.
- The Bicuspid valve ( Mitral valve) located between the left atrium and left ventricle allows the blood flow from left atria to left ventricle.
- Valves maintain the unidirectional flow of blood and thus prevent its back flow.