(3) Maintenance of Life _Part II

The FDA allows companies to label a product as having 0 grams of trans fat even if it contains up to 0.5 grams of trans fat.

Cookies and crackers were the most likely food products to still contain trans fats.

Even low levels of trans fats could pose a health risk, as there is no benefit to consuming them and they are not healthy for anyone.

The high levels of trans fats in baked goods pose a risk of heart disease.

The baked goods include puff pastries and cookies.

The term 'organic' refers to a molecule that contains carbon (C) and hydrogen (H), and is usually associated with living things.

Macromolecules are synthesized from basic building blocks of subunits and most of them exist as polymers, except for lipids which do not form polymers.

The process is called dehydration synthesis or condensation reaction. It is catalyzed by a polymerase enzyme.

Dehydration reactions are significant because they allow for the linking of monomers to form polymers, which are essential for storing energy and building complex structures in biological systems.

Hydrolysis is the process of splitting a polymer by adding water to a covalent bond, which is catalyzed by a hydrolase enzyme. This process results in the breaking of the bond between monomers, allowing for the release of energy that can be used to build other molecules.

In hydrolysis, a water molecule is added to a covalent bond in a polymer, which facilitates the breaking of that bond, resulting in the separation of the polymer into its monomer components.

Hydrolysis is significant in biological systems as it allows for the breakdown of complex macromolecules into simpler monomers, releasing energy that can be utilized for various cellular processes and building new molecules.

The four main types of carbon compounds are Carbohydrates, Lipids, Nucleic acids, and Proteins.

The incorrect statement is: 4. All of them can be made in absence of enzymes. Enzymes are crucial for the synthesis and breakdown of biological molecules.

Carbohydrates are characterized by the presence of the atomic grouping H-C-OH, which includes hydrogen, carbon, and hydroxyl groups.

The ratio of hydrogen atoms (H) to oxygen atoms (O) in carbohydrates is approximately 2:1, which is the same as the ratio in water, indicating their hydrophilic nature.

Carbohydrates serve as a source of quick and short-term energy storage in biological systems.

A monosaccharide is a carbohydrate with a low number of carbon atoms, typically ranging from 5 to 7. They serve as the building blocks of larger carbohydrates and can be found in nature or synthesized. The most common monosaccharide is glucose (C6H12O6).

Disaccharides are formed by the joining of two monosaccharides through a glycosidic linkage. The specific type of disaccharide created can vary based on the placement and combination of the bonds between the monosaccharides.

The molecular formula of sucrose is C12H22O11.

The glycosidic bond in disaccharides is significant because it determines the structure and properties of the disaccharide, influencing how the sugars interact and their biological functions.

Polysaccharides are a group of complex carbohydrates made up of many molecules of monosaccharides. They are formed through glycosidic bonds, which are the bonds that hold the separated monosaccharides together.

Polysaccharides are not sweet in taste, distinguishing them from simpler carbohydrates like monosaccharides and disaccharides.

Carbohydrates can be referred to as saccharides.

Carbohydrates are classified as simple or complex sugars.

Carbohydrates serve as an essential source of short-term energy.

Nutritionally, carbohydrates are not essential food sources, but they provide energy (calories).

Simple carbohydrates are found in foods such as fruits, milk, and vegetables. They include refined sugar products like cake and candy, which provide energy but lack essential vitamins, minerals, and fiber.

Complex carbohydrates provide vitamins, minerals, and fiber. They are found in foods such as breads, legumes, rice, pasta, and starchy vegetables.

The extracellular enzyme responsible for the digestion of Amylose, Amylopectin, and Glycogen is α Amylase.

The end products of Sucrose digestion are Glucose and Fructose.

Lactose is digested by Lactase, resulting in the end products Glucose and Galactose.

Trehalase is the enzyme that digests Trehalose, resulting in the end product Glucose.

Galactose is a nutritive sweetener found in:

• Dairy products
• Sugar beets
• It is also synthesized in the body and present in breastmilk.

Disaccharidases are enzymes that are required for the absorption and digestion of disaccharides such as sucrose, lactose, and maltose. They break down these sugars into their monosaccharide components, allowing for proper absorption in the intestine.

Human milk has higher concentrations of lactose than cow's milk, which contributes to its sweeter taste.

Maltose, known as malt sugar, is a disaccharide formed from two glucose molecules. The majority of maltose in the intestine comes from the digestion of starch.

Starch serves as a storage molecule in plants, allowing them to store energy for later use.

Glycogen is a storage molecule in animals, primarily found in the liver and muscles, where it stores energy that can be quickly mobilized when needed.

Cellulose is a major component of the plant cell wall, providing structural support and rigidity to plant cells.

Starch is a storage polysaccharide of plants that consists entirely of glucose monomers.

Plants store surplus starch as granules within chloroplasts and other plastids.

Glycogen is a storage polysaccharide in animals, primarily stored in the liver and muscle cells.

Glycogen consists of branched polymers of glucose, similar to amylopectin found in plants.

Polysaccharide cellulose is primarily found in plant cell walls, providing structural support and rigidity.

The glucose units in cellulose are joined by a slightly different type of linkage compared to the linkages in starch or glycogen.

Cellulose cannot be digested by humans due to the specific type of linkage between glucose units, which human digestive enzymes cannot break down.

Potatoes can be used as a food source because they contain starch, which our bodies can break down into glucose. In contrast, wood contains cellulose, which our bodies cannot digest due to the absence of the enzyme cellulase needed to break the bonds between glucose molecules in cellulose.

Complex sugars are mainly found in processed or refined food is incorrect; complex sugars are typically found in whole foods like grains, legumes, and vegetables.

The low-carb food pyramid consists of the following main components:

1. Fibrous Fruits: Kiwi, berries, and melon
2. Fats and Oils: Butter and olive oil
3. Nuts
4. Fibrous Vegetables: Lettuce, cucumbers, tomatoes, and broccoli
5. Eggs and Cheese
6. Proteins: Lobster, roast chicken, ham, and chicken drumsticks

A low-carb diet reprograms the body to burn fat for energy first, followed by carbohydrates.

Low-carb dieters can eat foods rich in protein such as:

1. Meats
2. Poultry
3. Fish
4. Eggs
5. Vegetable oils
6. Low-carb vegetables (e.g., salad greens)
7. Low-carb fruits (e.g., berries, melon)

Individuals can see results from a low-carb diet within the first 1-2 weeks.

A low-carb diet leads to a loss of water weight because carbohydrates are stored in the body with water molecules. When glycogen is used for energy, it releases water, creating a false impression of weight loss.

Low-carb diets are typically higher in fats and proteins, which take longer to digest, thereby increasing the feeling of fullness and reducing hunger.

Low-carb diets often lead to reduced overall calorie intake as they limit the variety of food consumption, resulting in a significant decrease in calorie intake.

A high animal protein diet can lead to:

1. Loss of calcium, increasing the risk of osteoporosis.
2. High levels of uric acid, raising the risk of gout.
3. Increased risk of kidney disease in individuals already at risk, such as those with diabetes or high blood pressure.

Low carbohydrate diets can cause:

• Dizziness, possibly due to dehydration.
• Constipation, due to low fiber intake.

The ketogenic diet primarily consists of 75% fats, 20% protein, and 5% carbohydrates.

The main metabolic state achieved by following a ketogenic diet is ketosis, where the body breaks down protein and fat for energy instead of carbohydrates.

The ketogenic diet is supposed to be a short-term diet focused on weight loss.

There is a lack of substantial evidence on the health benefits of the ketogenic diet.

1. Amylose and amylopectin are both forms of starch. Amylase is an enzyme that breaks down starch, while cellulose is a structural component of plant cell walls and not a starch. Amylopactase is not a recognized term in this context.

Bread will replace rice as the major calorie intake is INCORRECT; low-carb diets typically reduce carbohydrate intake, including bread and rice.

Lipids have little or no affinity for water, making them hydrophobic due to their composition of hydrocarbons that form non-polar covalent bonds.

Lipids are considered hydrophobic because they consist mostly of hydrocarbons, which form non-polar covalent bonds, resulting in little or no affinity for water.

The most biologically important lipids are fats, phospholipids, and steroids.

No, lipids are the one class of large biological molecules that do not form polymers.

Fats are constructed from glycerol and fatty acids.

Glycerol is a three-carbon alcohol with a hydroxyl group attached to each carbon.

A fatty acid consists of a carboxyl group attached to a long carbon skeleton.

When three fatty acids are joined to glycerol, they create a triacylglycerol, also known as a triglyceride.

The process is called dehydration synthesis, which involves the removal of water molecules to form ester linkages between glycerol and fatty acids.

A triglyceride molecule is composed of one glycerol molecule and three fatty acid molecules linked together through ester bonds.

The bond formed between glycerol and fatty acids in triglycerides is called an ester linkage.

The dehydration reactions are significant because they facilitate the formation of ester linkages, which are essential for creating the triglyceride structure from glycerol and fatty acids.

Saturated fatty acids have the maximum number of hydrogen atoms possible and no double bonds, while unsaturated fatty acids contain one or more double bonds.

A diet rich in saturated fats may contribute to cardiovascular disease through the formation of plaque deposits in the arteries.

Unsaturated fats are liquid at room temperature due to the presence of one or more double bonds in their fatty acid chains. These double bonds create kinks in the structure, preventing the molecules from packing closely together. This loose arrangement results in a lower melting point compared to saturated fats, which have no double bonds and can pack tightly, making them solid at room temperature.

Saturated fatty acids have no double bonds between carbon atoms, resulting in a straight chain structure. In contrast, unsaturated fatty acids contain one or more double bonds, causing a bend in the chain due to the presence of a cis double bond.

The cis double bond in unsaturated fatty acids causes a bending in the molecular structure, which affects the physical properties of the fat, such as its melting point and fluidity.

Hydrogenation is the process of converting unsaturated fats to saturated fats by adding hydrogen. This process can lead to the formation of trans fats when vegetable oils are partially hydrogenated, resulting in unsaturated fats with trans double bonds.

Trans fats may contribute more to cardiovascular disease than saturated fats, despite both being types of fats. The presence of trans double bonds in trans fats is associated with increased health risks.

The legal limit for trans fats in processed food set by the EU from 2021 is 2 g per 100 g of fat.

Trans fatty acids (TFAs) occur naturally in small amounts in certain foods such as meat and cheese.

The primary public health risk associated with trans fats is related to industrial or artificial trans fats, which are produced by partially hydrogenating vegetable oils and are linked to non-communicable diseases such as heart disease and stroke.

High levels of trans fat consumption are associated with non-communicable diseases such as heart disease, stroke, and a higher risk of developing type 2 diabetes.

Industrially produced trans fats are associated with an increased risk of heart disease.

The goal set by WHO and its Member States is to eliminate industrially produced trans fats from the food supply by 2023.

The Eurasian Economic Union, the European Union, and individual countries in the Region are taking measures to eliminate trans fats.

Many countries in the Region have already taken strong action, moving closer to becoming the first WHO region in the world to become trans-fat free.

About 84 percent of food products that contain trans fats still carry a 'zero gram' label.

The report indicates that these baked goods contain unsaturated fats above the recommended daily consumption.

Lipids serve several structural roles, including:

1. Cell Membrane Composition: Lipids and phospholipids are essential components of cell membranes, providing structural integrity and fluidity.
2. Protective Wax Cuticle: They form a protective wax cuticle on the outside of leaves, helping to prevent water loss.
3. Heat Insulation: In animals, lipids provide heat insulation, helping to maintain body temperature.
4. Organ Protection: Lipids protect internal organs in animals by providing cushioning and support.

A phospholipid consists of two fatty acids, a phosphate group, and a glycerol backbone.

The two fatty acid tails are hydrophobic (water-repelling), while the phosphate group and its attachments form a hydrophilic head (water-attracting).

Phospholipids self-assemble into a bilayer, with the hydrophobic tails pointing toward the interior and the hydrophilic heads facing outward toward the water.

The bilayer arrangement of phospholipids is crucial as it forms the major component of all cell membranes, providing a barrier that separates the interior of the cell from the external environment.

Steroids are characterized by a carbon skeleton consisting of four fused rings, which include three cyclohexane rings and one cyclopentane ring.

Cholesterol is an important steroid that serves as a component in animal cell membranes.

High levels of cholesterol in the blood may contribute to cardiovascular disease.

The two essential sex hormones that are classified as steroids are testosterone and estradiol.

HDL (High-Density Lipoprotein) helps to transport and remove bad cholesterol from the bloodstream, while LDL (Low-Density Lipoprotein) is considered bad cholesterol as it can lead to plaque build-up and atherosclerosis.

In the bloodstream, 75% of cholesterol is made by our body, while 25% comes from food sources, particularly animal products which contain high levels of cholesterol.

Too much cholesterol can lead to health risks such as plaque build-up in arteries, which can result in atherosclerosis and other cardiovascular diseases.

Cholesterol is important as a cell membrane component and for hormone synthesis. A small amount is sufficient for these functions, but excess can be harmful.

• More fruits and vegetables
• Less red and processed meat
• Choose whole grains instead of refined grains
• Include nonfat dairy foods, legumes, nuts, and seafood
• Reduce foods with added sugars, saturated fat, and sodium
• Moderate consumption of eggs is now considered acceptable, with research showing a weak link between dietary cholesterol and blood cholesterol levels.

• More fruits and vegetables
• Less red and processed meat
• Whole grains instead of refined grains
• Nonfat dairy foods, legumes, nuts, and seafood
• Fewer foods with added sugars, saturated fat, and sodium
• Moderate egg consumption (up to one egg a day) is considered acceptable

About 80% of the cholesterol in the bloodstream is produced by the body, while only 20% comes from food.

Cholesterol is vital for several functions, including:

1. Building block in cell membranes
2. Production of vitamin D
3. Synthesis of hormones (like testosterone and estrogen)
4. Formation of fat-dissolving bile acids

Cholesterol is viewed negatively because excess cholesterol in the bloodstream contributes to artery-clogging plaque, which can lead to heart disease and increase the risk of heart attacks.

Scientists now emphasize the importance of studying humans rather than relying primarily on experimental animals like rabbits, which do not process cholesterol effectively due to their herbivorous diet.

• Energy storage: Lipids provide more than twice the energy of carbohydrates or proteins.
• Energy source: The energy from lipids is released during respiration.
• Absorption of fat-soluble vitamins: Lipids aid in the absorption of vitamins such as A, D, E, and K.
• Hormonal functions: Some lipids function as hormones, playing crucial roles in various physiological processes.

The extracellular enzymes involved in the digestion of triglycerides are Lipase and Colipase, resulting in the end products of B-mono-glyceride and Fatty Acids.

The digestion of phospholipids involves the extracellular enzyme Phospholipase and the intestinal mucosal enzyme Phosphatase, resulting in the end products of Alcohols, Fatty Acids, and Phosphate.

Cholesterol Esterase is the extracellular enzyme involved in the digestion of cholesterol esters, producing Cholesterol and Fatty Acid as end products.

The digestion of waxes involves the extracellular enzyme Lipase, resulting in the end products of Monohydric Alcohol and Fatty Acid.

Bile salts from the liver emulsify fats by breaking down large fat globules into smaller droplets, increasing the lipid surface area for enzymatic exposure.

Emulsification increases the lipid surface area, allowing lipase from pancreatic juice to more effectively cleave off fatty acids from the fat droplets.

Emulsification is the process where large fat droplets from the stomach are acted upon by bile salts from the liver, forming smaller emulsion droplets that facilitate digestion.

Digestion of dietary fats primarily occurs in the emulsion droplets formed during the emulsification process.

Micelles, formed from monoglycerides and fatty acids associating with bile salts and phospholipids, transport lipids to the surface of enterocytes (intestinal absorptive cells) for absorption.

Monoglycerides and fatty acids are re-synthesized into triglycerides and packaged into chylomicrons along with cholesterol and fat-soluble vitamins.

Chylomicrons are lipoproteins designed for the transport of lipids in the circulation. They are released by exocytosis and enter lacteals (lymphatic capillaries) due to their large size, eventually flowing into the general circulation via lymphatic vessels.

Fat serves several important functions in the body:

1. Energy Source: Provides a significant source of energy.
2. Brain Composition: Comprises about 60% of the brain's structure.
3. Cell Membrane Structure: Acts as building blocks for cell membranes and hormones.
4. Nutrient Absorption: Aids in the absorption of vitamins and minerals.

Trans fats are considered bad fats that can negatively impact health.

Consuming the right amount of fat is crucial because:

• It supports essential bodily functions.
• It helps maintain overall health and well-being.
• Excessive intake of bad fats can lead to health issues.

The oxidation of cholesterol initiates the inflammatory response in atherosclerosis.

Macrophages eat and digest cholesterol, turning into foam cells that accumulate to form plaques.

The covering of plaques by smooth muscle cells reduces blood flow and may even result in a blood clot.

The saturation of a lipid is determined by the structure of its fatty acids. Specifically, the presence of double bonds in the fatty acid chains indicates that the lipid is unsaturated, while the absence of double bonds indicates that it is saturated. Therefore, the correct answer is Fatty Acid 1, 2, and 3.

Emulsification is the process that facilitates lipid digestion and absorption by breaking down fats into smaller droplets, increasing the surface area for lipase action.

Testosterone is primarily responsible for:

1. Development of male reproductive tissues such as the testes and prostate.
2. Promotion of secondary sexual characteristics including increased muscle and bone mass, and the growth of body hair.
3. Regulation of libido (sex drive) and sexual function.
4. Influencing mood and energy levels.
5. Supporting sperm production.

Estrogen is primarily responsible for:

1. Regulating the menstrual cycle and reproductive system.
2. Development of female secondary sexual characteristics such as breast development and body fat distribution.
3. Maintaining bone density and cardiovascular health.
4. Influencing mood and cognitive function.
5. Supporting pregnancy and fetal development.

The pituitary gland, located in the center of the brain, tells the testicles to produce testosterone.

Low testosterone can lead to reduced muscle mass and strength, as well as increased body fat, such as a 'pot belly.'

Prolonged periods of low testosterone decrease bone density, increasing the risk of osteoporosis.

Low testosterone can lead to problems achieving or maintaining erections.

The brain regulates testosterone production by sending a signal to the pituitary gland.

The testicles produce testosterone and help maintain normal levels in the body.

Creatine and DHEA can raise testosterone levels, which then converts to Dihydrotestosterone (DHT). DHT is known to attack hair follicles, potentially speeding up the hair-thinning process, particularly in men predisposed to male pattern baldness.

The Guevedoces males are affected by a deficiency in the enzyme 5-alpha-reductase, which prevents the conversion of testosterone into dihydro-testosterone, leading to the absence of male genitalia at birth.

At puberty, Guevedoces males experience a second surge of testosterone, which leads to the development of male characteristics such as muscles, testes, and a penis.

The Guevedoces condition illustrates that despite having an XY chromosome, the physical development of males can be influenced by genetic factors, such as the deficiency of the enzyme 5-alpha-reductase, affecting the expression of male genitalia until puberty.

Estrogen helps to:

• Maintain body temperature
• Potentially delay memory loss
• Regulate parts of the brain for sexual and reproductive development

Estrogen helps to preserve bone density, which is crucial for maintaining strong bones and preventing osteoporosis.

Estrogen stimulates the development of the breasts at puberty and prepares the glands for future milk production.

Estrogen helps to regulate the liver's production of cholesterol, decreasing plaque buildup in coronary arteries and lowering the risk of heart attack.

Some research suggests that prolonged exposure to estrogen may increase a woman's risk of breast cancer.

Anabolic steroids are drugs that mimic the effects of testosterone in the body. They primarily increase protein synthesis within cells, particularly in skeletal muscles, leading to enhanced muscle growth and development. Additionally, they contribute to the development and maintenance of masculine characteristics.

Anabolic steroid use is growing rapidly in Britain's gyms, leading to the installation of needle bins as the number of users surpasses that of heroin addicts who inject.

The study confirmed that synthetic anabolic androgenic steroids, injectable testosterone, and adjunctive therapies can be easily purchased over the Internet without a prescription.

The study examined synthetic anabolic steroids, injectable testosterone, recovery agents, erectile dysfunction medications, herbal supplements, and non-steroid hormones commonly abused with steroids, such as human growth hormone and insulin-like growth factor.

Despite the Covid lockdown, there has been a sustained growth in the use of anabolic steroids, with an increase in the number of units seized by authorities.

More than 120,000 anabolic steroid units were seized last year, compared to just under 100,000 the previous year.

The Health Protection Regulation Agency (HPRA) is responsible for overseeing the use of medicines in Ireland, including anabolic steroids.

Bodybuilding supplements containing steroids or steroid-like substances can lead to serious health risks, including:

1. Liver injury - Some cases can be life-threatening.
2. Severe acne
3. Hair loss
4. Altered mood
5. Irritability
6. Increased aggression
7. Depression
8. Kidney damage
9. Heart attack
10. Stroke
11. Pulmonary embolism (blood clots in the lungs)
12. Deep vein thrombosis (blood clots in deep veins)

Young adults under 25 have reported medical issues linked to dietary supplement use, with some supplements posing greater risks than others. Additionally, supplements are not regulated like medications, leading to uncertainty about their contents.

Researchers found that some bodybuilding supplements contained anabolic steroids that were not listed on the label, indicating a risk of undisclosed synthetic steroids that mimic testosterone.

Unapproved prescription drugs masquerading as dietary supplements can pose significant risks to consumers, including life-threatening reactions such as liver toxicity, heart attack, and stroke.

Cochcroft misled consumers by using fictitious business names, multiple addresses, collaborating with Chinese suppliers to mislabel drug products, and failing to seek FDA approval for his products.

The FDA has cautioned against the use of SARMs, highlighting their association with serious health risks and the requirement for FDA approval before lawful distribution.