Enzymes are proteins and they control the speed of chemical reactions in your body. Without them, the reactions would happen too slowly to keep you alive.
Some break down larger molecules into smaller ones and those enzymes are in your stomach.
Answer: A. before history was written.
Explanation:
I'm not sure if you need an explanation, but prehistoric means "very old or out of date." Hope this helps, Good luck! :)
Answer:
The process of respiration in plants involves using the sugars produced during photosynthesis plus oxygen to produce energy for plant growth. In many ways, respiration is the opposite of photosynthesis. In the natural environment, plants produce their own food to survive.As with photosynthesis, plants get oxygen from the air through the stomata. Respiration takes place in the mitochondria of the cell in the presence of oxygen, which is called "aerobic respiration".
In plants, there are two types of respiration: dark respiration and photo respiration. The first kind occurs in the presence or absence of light, while the second occurs exclusively in the presence of light.<em>Plant respiration occurs 24 hours per day</em>, but <em>night respiration is more evident since the photosynthesis process ceases.</em> During the night, it is very important that the <em>temperature is cooler than during the day</em> because plants can experience stress. Imagine a runner in a marathon.
roots respire too!
One of the functions of the substrate is <em>to serve as a site for air exchange between the root zone and atmosphere</em>. In other words, <em>roots breathe oxygen like we do</em>. Different plants have different oxygen requirements for their root systems.
For example,
<em><u>the root system of a poinsettia requires a lot of oxygen, so it is best to use a substrate with high air porosity, while hostas can live well in a substrate with a high water holding capacity. </u></em>
The proteins are called Histone proteins. Chromosomal DNA is packaged such that the strands of DNA are wound around histone proteins and fold into complex ways to form chromosomes. The histone proteins are positively charged proteins that strongly adhere to negatively charged DNA and form complexes called nucleosomes. Each nucleosome is composed of double-helical DNA wrapped.
