Covalent Bonds hold together atoms within a molecule
Answer:
A circuit is a closed loop that electrons can travel in. A source of electricity, such as a battery, provides electrical energy in the circuit. Generally, there is some appliance that uses electricity in the circuit. The appliance may, for example, provide light or heat or mechanical energy.
Explanation:
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!
Cohesion. Cohesion is the property of water that attracts other water molecules so they can stick together. Water is sticky because it has positive and negative charge in the oxygen and hydrogen ends that attracts one water molecule to another. Adhesion is also a property of water that attracts it from other substances, making it easy for water to travel upwards through transpiration.
Answer:
Small external openings of lungs help in two ways:
1. It helps in trapping the dust and pathogens like bacteria, fungal spores et cetera. Larger opening would provide dust and pathogen a wider area to enter into the body.
2. The smaller opening prevents the drying of the respiratory membrane. A moist membrane is essential for the successful exchange of oxygen and carbon dioxide in the lungs.