why are leaves red in the fall?
The red color of leaves in the fall is due to pigments called anthocyanins. Anthocyanins are responsible for the red, purple, and blue hues seen in various plants and fruits.
During the spring and summer, chlorophyll pigments dominate and give leaves their green color. Chlorophyll is essential for photosynthesis, the process by which plants convert sunlight into energy. However, as days become shorter and temperatures drop in the fall, the production of chlorophyll decreases.
As the chlorophyll breaks down, other pigments, including anthocyanins, become more visible. Anthocyanins are produced in leaves to protect them from high light intensity and to act as a natural sunscreen. They also help to prolong the life of leaves, allowing plants to maximize the nutrients that can be withdrawn before the leaves ultimately fall.
The red coloration of leaves in the fall is influenced by other factors such as sunlight, temperature, and the accumulation of sugars in the leaves. These factors can vary from year to year, resulting in variations in the intensity and timing of the red color display during fall.
is "The Calvin cycle is the light-independent (does not need light) step of photosynthesis and happens in the stroma" true or false?
True. The Calvin cycle is the light-independent step of photosynthesis and occurs in the stroma of the chloroplasts. It is named after Melvin Calvin, who elucidated this process. In the Calvin cycle, carbon dioxide (CO2) is converted into glucose using ATP and NADPH generated during the light-dependent reactions. The stroma is the fluid-filled space surrounding the thylakoid membranes where the Calvin cycle takes place.
what is the equation for cellular respritation?
The equation for cellular respiration is:
C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP
This equation represents the aerobic respiration of glucose, which is the most common form of cellular respiration. In this process, glucose (C6H12O6) reacts with oxygen (O2) to produce carbon dioxide (CO2) and water (H2O) as byproducts, along with the release of energy in the form of adenosine triphosphate (ATP).
what is the equation for latic acid fermentation?
The equation for lactic acid fermentation is:
C6H12O6 → 2C3H6O3
In lactic acid fermentation, glucose (C6H12O6) is converted into lactic acid (C3H6O3) without the involvement of oxygen. This process occurs in certain microorganisms, including bacteria and muscle cells, when there is an insufficient supply of oxygen for aerobic respiration. Lactic acid fermentation is important in producing energy in the absence of oxygen, and it is commonly observed during intense exercise when the muscles cannot get enough oxygen to meet the energy demands.
in the kerbs cycle, how is citric acid formed?
In the Krebs cycle, also known as the citric acid cycle or tricarboxylic acid (TCA) cycle, citric acid is formed through a series of enzyme-catalyzed reactions. Here is a simplified overview:
1. Acetyl-CoA, derived from the breakdown of glucose or fatty acids, joins with oxaloacetate (a four-carbon molecule) to form citrate (also known as citric acid), a six-carbon molecule.
Acetyl-CoA + Oxaloacetate → Citrate
2. Citrate is then isomerized to isocitrate, which undergoes oxidative decarboxylation.
Citrate → Isocitrate
3. Isocitrate is further converted into alpha-ketoglutarate. This step releases a molecule of carbon dioxide and reduces NAD+ to NADH.
Isocitrate → Alpha-ketoglutarate + CO2
4. Alpha-ketoglutarate is decarboxylated, producing another molecule of carbon dioxide and reducing NAD+ to NADH. This step also generates a molecule of Guanosine-5'-triphosphate (GTP) which can be subsequently converted to ATP.
Alpha-ketoglutarate + CoA + NAD+ → Succinyl-CoA + NADH + CO2
5. Succinyl-CoA is converted into Succinate, producing another molecule of GTP.
Succinyl-CoA + GDP + Pi → Succinate + GDP + CoA + GTP
6. Succinate is converted into Fumarate by losing two electrons, which are accepted by FAD (Flavin adenine dinucleotide) to form FADH2.
Succinate + FAD → Fumarate + FADH2
7. Fumarate is then converted into Malate.
Fumarate + H2O → Malate
8. Malate is oxidized, producing oxaloacetate. NAD+ is reduced to NADH in this step.
Malate + NAD+ → Oxaloacetate + NADH
Oxaloacetate formed at the end of the Krebs cycle can then start the cycle again by combining with Acetyl-CoA, and the process continues.
the following are steps of cellular respritation except
electrolysis
the kerbs cycle
electron transport chain
glycolysis