Answer:
D. There is no enough oxygen in the culture fluid
Explanation:
The cells in the test tube need to carryout one of the important metabolic processes of living organisms - respiration. The process involves the breakdown of glucose to generate energy for other metabolic processes in the cell.
Respiration can be carried out in the presence of oxygen (aerobic) or in the absence of oxygen (anaerobic). Human cells are primarily aerobic but can carryout respiration anaerobically in the presence of inadequate oxygen.
For aerobic respiration, glucose is broken down in the presence of oxygen to produce carbon-dioxide, water and energy in the form of ATP:
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<em>In the absence of oxygen, the glucose becomes converted to lactic acid and a smaller amount of ATP is produced as compared to aerobic respiration.</em>
<em>Hence, lactic acid gradually builds up in the absence of oxygen due to anaerobic respiration.</em>
The correct option is D.
A short period of time, after the onset of puberty. The first mature eggs starts to be released from the ovaries during menstruation. Menstruation may first occur during the start of puberty in women, it may start as early as 8 years old and can start late as 16 years old. Menstruation is the process wherein not fertilized eggs are being broken down and released from the body.
Answer: the amount of silica minerals in granite
Explanation:
Usually, 70-77 percent silica, 11-13 percent alumina, 3-5 percent potassium oxide, 3-5 percent soda, 1 percent lime, 2-3 percent total iron, and less than 1 percent magnesia and titania are the chemical composition of granite. Rhyolite is another kind of volcanic rock with a similar or equivalent chemical composition and mineralogy. Due to high precense of silica the color of granite appears lighter.
A simple example is a connection between the circulatory and respiratory systems. <span>As </span>blood<span> circulates through your body, it eventually needs fresh oxygen </span><span>from the air. When the </span>blood<span> reaches the lungs, part of the </span>respiratory system<span>, the </span>blood<span> is re-oxygenated.</span>