1)State two differences between glycosis and Krebs cycle
2)Compare between respiration and photosynthesis
3)State two situations where the rate of respiration rises above normal
4)Define the following terms;
a)Oxygen debt
b)Respiratory quotient
5)Study the equation below and answer the equations below;
2C51 H95 O6+145O2-102Co2+98H2O+energy;
a)Calculate the respiratory quotient
b)Identify the food substrate
6)Two applications of anaerobic respiration
7)State two differences between aerobic and anaerobic respiration
8)Describe the;
a)Krebs cycle
b)Glycoysis
9)Name the site of gaseous exchange in;
a)Mammals
b)Paramecium
c)Roots
d)Frogs
e)Insects
10)State four characteristics of respiratory surfaces
11)Describe how oxygen enters the haemolymph of an insect
12)Draw and label the gill from a bony fish
1) Two differences between glycolysis and Krebs cycle are:
- Glycolysis occurs in the cytoplasm of cells, while Krebs cycle occurs in the mitochondria.
- Glycolysis produces a net gain of 2 ATP molecules and 2 NADH molecules, while Krebs cycle produces 2 ATP molecules, 6 NADH molecules, and 2 FADH2 molecules.
2) Respiration and photosynthesis are two opposite metabolic processes that occur in living organisms. Respiration is the breakdown of food molecules (usually glucose) to release energy in the form of ATP, while photosynthesis is the conversion of light energy into chemical energy (glucose) by plants and some other organisms. Some comparisons between respiration and photosynthesis are:
- Respiration releases carbon dioxide and water as waste products, while photosynthesis uses carbon dioxide and water as reactants to produce oxygen as a waste product.
- Respiration occurs in all living cells, while photosynthesis only occurs in some organisms with specialized structures (e.g. chloroplasts in plants).
3) Two situations where the rate of respiration rises above normal are:
- During exercise, when muscle cells require more energy to contract and maintain their functions.
- During fever, when body temperature increases and more energy is needed to maintain homeostasis.
4) The definitions of the terms are:
- Oxygen debt: The temporary shortage of oxygen in the body tissues after strenuous exercise, due to the buildup of lactic acid and other byproducts of anaerobic respiration.
- Respiratory quotient: The ratio of carbon dioxide produced to oxygen consumed during respiration, which reflects the type of substrate being metabolized (e.g. carbohydrates, fats, proteins).
5) For the equation 2C51 H95 O6+145O2-102Co2+98H2O+energy:
- The respiratory quotient is 0.7 (calculated as the ratio of CO2 produced to O2 consumed).
- The food substrate is a lipid (since it has a high ratio of carbon to hydrogen atoms).
6) Two applications of anaerobic respiration are:
- Producing alcoholic beverages and bread dough by yeast cells.
- Generating energy in certain bacteria, such as those in the gut of animals and in some extreme environments where oxygen is absent.
7) Two differences between aerobic and anaerobic respiration are:
- Aerobic respiration requires oxygen as the final electron acceptor in the electron transport chain, while anaerobic respiration uses other molecules (such as nitrate or sulfate) or fermentation pathways.
- Aerobic respiration yields much more ATP per glucose molecule than anaerobic respiration (38 ATP vs 2 ATP in humans).
8) The descriptions of the two processes are:
- Krebs cycle: A series of enzymatic reactions that occur in the mitochondrial matrix and oxidize acetyl-CoA (generated from the breakdown of glucose, fatty acids, or amino acids) to release carbon dioxide, hydrogen atoms, and ATP. The Krebs cycle also yields intermediates that feed into other metabolic pathways, such as the electron transport chain and gluconeogenesis.
- Glycolysis: A series of enzymatic reactions that occur in the cytoplasm of cells and break down glucose (or other sugars) into pyruvate, generating ATP and NADH in the process. Glycolysis can produce energy either aerobically or anaerobically, depending on the availability of oxygen.
9) The sites of gaseous exchange in different organisms are:
- Mammals: The alveoli of the lungs.
- Paramecium: The cell membrane and cytoplasm.
- Roots: The root hairs and intercellular spaces.
- Frogs: The skin and the lungs (when submerged).
- Insects: The tracheal tubes and tracheoles.
10) Four characteristics of respiratory surfaces are:
- Large surface area to volume ratio, to maximize gas exchange.
- Thin and moist, to facilitate diffusion across the membrane.
- Close proximity to a transport system, to ensure rapid exchange of gases.
- Selectively permeable, to allow the exchange of specific gases while preventing the loss of water.
11) Oxygen enters the haemolymph of an insect through a series of tracheal tubes that penetrate the body tissues. The tracheal tubes are lined with chitin and are connected to external openings called spiracles. When an insect needs oxygen, it opens the spiracles and allows air to flow into the tracheae. The oxygen diffuses through the moist walls of the tracheae and into the haemolymph, where it binds to haemoglobin or dissolves in the plasma.
12) I'm sorry, I cannot draw a diagram as I am a text-based program.
1) Two differences between glycolysis and Krebs cycle are:
- Location: Glycolysis takes place in the cytoplasm of the cell, while the Krebs cycle occurs in the mitochondria.
- Production of ATP: Glycolysis produces a small amount of ATP (2 molecules), while the Krebs cycle generates a larger amount of ATP (up to 24 molecules).
2) Comparison between respiration and photosynthesis:
- Energy Source: Respiration involves the breakdown of organic molecules (such as glucose) to release energy, while photosynthesis uses light energy to convert carbon dioxide and water into glucose and oxygen.
- End Products: Respiration generates carbon dioxide and water as metabolic byproducts, while photosynthesis produces glucose and oxygen.
3) Two situations where the rate of respiration rises above normal are:
- During exercise or physical activity: Muscles require more energy during exercise, leading to an increase in respiration rate.
- Fever or illness: Infections or illnesses can raise the body's metabolic rate, resulting in an elevated respiration rate.
4) Definitions of the following terms:
a) Oxygen Debt: Oxygen debt refers to the amount of oxygen required to restore normal levels of oxygen in the body following strenuous exercise. It is used to metabolize the lactic acid built up during anaerobic respiration.
b) Respiratory Quotient: The respiratory quotient (RQ) is the ratio of the amount of carbon dioxide (CO2) produced to the amount of oxygen (O2) consumed during cellular respiration. It provides information about the type of substrate being used for respiration. RQ values range from 0.7 to 1.0, with different ratios corresponding to different substrates.
5) Studying the given equation:
2C51 H95 O6 + 145O2 - 102CO2 + 98H2O + energy
a) To calculate the respiratory quotient (RQ), we compare the ratio of CO2 produced to O2 consumed. In this equation, the ratio is 102CO2:145O2, which simplifies to 0.703. Therefore, the respiratory quotient is 0.703.
b) Based on the equation, the food substrate being used for respiration is a complex organic molecule with the formula C51 H95 O6.
6) Two applications of anaerobic respiration are:
- Production of alcoholic beverages: Anaerobic respiration carried out by yeast converts glucose into ethanol and carbon dioxide, which is utilized in the fermentation process to produce alcoholic beverages like beer and wine.
- Biogas production: Anaerobic bacteria break down organic matter in the absence of oxygen to produce biogas, which mainly consists of methane and carbon dioxide. This process is utilized in biogas plants to produce renewable energy.
7) Two differences between aerobic and anaerobic respiration are:
- Oxygen Requirement: Aerobic respiration requires oxygen to take place, while anaerobic respiration occurs in the absence of oxygen.
- ATP Production: Aerobic respiration produces a larger amount of ATP through the complete breakdown of organic molecules, while anaerobic respiration generates a smaller amount of ATP due to partial breakdown or fermentation.
8) Descriptions of the following:
a) Krebs cycle: The Krebs cycle, also known as the citric acid cycle, is a series of chemical reactions that occur in the mitochondria of cells. It is the second stage of cellular respiration and occurs after glycolysis. During the Krebs cycle, acetyl-CoA, derived from the breakdown of glucose or fatty acids, is oxidized, resulting in the production of ATP, NADH, FADH2, and carbon dioxide as a byproduct.
b) Glycolysis: Glycolysis is the initial stage of cellular respiration and occurs in the cytoplasm of the cell. It involves the breakdown of glucose molecule into two molecules of pyruvate through a series of enzymatic reactions. Glycolysis produces a small amount of ATP and NADH.
9) Sites of gaseous exchange in:
a) Mammals: The site of gaseous exchange in mammals is the alveoli of the lungs.
b) Paramecium: Paramecium exchange gases primarily through their cell membrane.
c) Roots: In roots, gaseous exchange occurs in the air spaces within the soil.
d) Frogs: Frogs mainly exchange gases through their moist skin.
e) Insects: Insects have tiny tubes called tracheae that carry gases directly to and from their cells.
10) Four characteristics of respiratory surfaces include:
- Large surface area: Respiratory surfaces tend to have a large surface area to maximize gas exchange.
- Thin and permeable: The respiratory surface should be thin and permeable to allow for the diffusion of gases.
- Moist: Moisture helps facilitate the exchange of gases through respiratory surfaces.
- Rich blood supply: An extensive network of blood vessels near the respiratory surface ensures efficient exchange of gases with the circulatory system.
11) Oxygen enters the haemolymph of an insect through a network of tubes called tracheae. These tracheae open to the external environment through small openings called spiracles. Oxygen diffuses directly from the atmosphere into the tracheae and then dissolves in the haemolymph for distribution to the cells.
12) Unfortunately, as an AI text-based assistant, I am unable to draw or label images. I can provide you with a verbal description of the gill structure in a bony fish if that would be helpful to you.