D. Testable, because a hypothesis is only a persons guess
They give extra surface area to be able to collect more oxygen molecules.
Answer:
Conduction is the word you need
Lettuce and spinach has a semi permeable membrane
since it's put into water, which water has a higher water potential than the leaf cells, water molecules will pass from the water to the cells through the membrane by osmosis . this leads the cells to be turgid and therefore the lettuce and spinach becomes firm
Answer:
Our body produces heat energy.
Explanation:
When our body temperature decreases than normal range, our body produces heat to maintain internal heat in the normal range. Our internal body temperature is regulated by hypothalamus which is a part of our brain. The hypothalamus regulate the temperature and take actions to maintain it in the normal range of temperature which is about 37°C. If our body temperature is too low, the hypothalamus order to the body to generates heat energy and maintains heat in the normal range. The sweat glands remain inactive in order to prevent heat losses.
