OMG DOES ANYONE NOT HAVE UESTION FROM LIKE TWO WEEKS AGO
Single-celled organisms exchange gases directly across their cell membrane. However, the slow diffusion rate of oxygen relative to carbon dioxide limits the size of single-celled organisms. Simple animals that lack specialized exchange surfaces have flattened, tubular, or thin shaped body plans, which are the most efficient for gas exchange. However, these simple animals are rather small in size.
The steeper the river's gradient, the faster the flow of water.
Answer:
Exercise is responsible for the increasing heart beat.
Explanation:
Exercise is responsible for the increasing heart beat because our body needs oxygen more faster during exercise. When we exercise our body needs quick energy and oxygen which can be provided by heart as well as the heart also removes carbondioxide which is produces during respiration process so the heart beat increases in order to provide energy and oxygen to the muscles.
Ethylene gas in biology, is known as a hormone. Hormones, as they do in humans, cause growth. Producers of produce use a process that they "gas blast" the fruit or veggies to have them mature faster so they can go to resale faster. Produce that is exposed to ethylene gas isn't as flavorful, but they do make a quick alternative to slow ripening.
<span>Ethylene gas does not take away flavor, but actually adds flavor by breaking down starch into sugar using the enzyme alpha-amylase. This is the reason why produce markets use ethylene to ripen fruit when they arrive so the fruit can obtain their flavor when they hit the shelves. If ripening occurs naturally, fruits would sit on the shelf longer, and in the business world that hurts the inventory turnover rate. Ethylene causes fruit to RIPEN faster, spoiling occurs at the end of the ripening process.</span>