Metabolism is the range of chemical reactions necessary for survival in living organisms. It includes processes like growth, reproduction, structural maintenance, and responsiveness to the environment (Metabolism). These reactions convert consumed food into vital energy that our bodies need. Metabolism can be divided into two main categories: Anabolism and Catabolism. These divisions help facilitate the chemical reaction process. Special proteins within the body closely regulate these metabolic reactions, which are closely connected to other bodily functions (Dowshen).
Metabolism is essential for the survival of all living creatures, including humans. It is a continuous process that begins at birth and persists until death. The key elements of metabolism revolve around food consumption and our digestive system. In the digestive system, enzymes break down proteins into amino acids, fats into fatty acids, and carbohydrates into simple sugars such as glucose. Apart from glucose, both amino acids and fatty acids can serve as energy sources for the body when needed.
When these compounds enter the bloodstream, they are transported to cells in different parts of the body. Inside these cells, certain enzymes facilitate and regulate the necessary chemical reactions for metabolizing these compounds. This allows the body to either use their energy or store it in organs like the liver, muscles, and body fat. Essentially, metabolism involves a coordinated interplay between two distinct activities.
These are the building up of body tissues and storing energy, then breaking down the body tissues and energy stored to generate more fuel for body function.
These are the roles of Anabolism and Catabolism (Dowshen).
“Anabolism, also known as biosynthesis, is the process by which organisms make complex molecules and substances from less complex components.” (Liden)
Anabolism leads to growth in organisms as molecules are produced from smaller components and added to bones or muscles.
The process of growth relies on raw components and energy generated through catabolism, which breaks down large molecules into simpler substances. Anabolic and catabolic processes together form metabolism, the series of chemical reactions that sustain life in organisms. Anabolic processes produce the majority of the chemicals found in organisms.
Both anabolism and catabolism are crucial processes in the body’s metabolism. Anabolism is responsible for producing important substances like proteins, lipids, and nucleic acids that are vital for development, growth, maintenance, and repair. It converts simple molecules into more complex ones. In contrast, catabolism complements anabolism by breaking down large and complex molecules into simpler forms. This breakdown provides raw materials and energy that can be utilized in anabolic processes. Digestion is a well-known example of catabolism.
Anabolism is the process of generating new molecules, while catabolism involves the breakdown of molecules. The energy released during catabolism serves various purposes: it fuels anabolism, produces body heat, and helps with muscle contraction and movement. Catabolism transforms complex chemicals into simpler substances and eliminates waste via the skin, kidneys, lungs, and intestines. When anabolic activity exceeds catabolic activity, there is overall growth; however, if catabolism outweighs anabolism, there is a net loss (Liden).
Metabolism is the key factor in determining weight gain or loss. Hormones associated with metabolism can be categorized as anabolic or catabolic, depending on their effects on anabolic or catabolic pathways. Specific hormones are necessary for proper metabolic function, while others may be used artificially to enhance growth, strength, and energy levels through legal or illegal methods. For example, anabolic steroids have legitimate medical uses such as treating delayed puberty.
These substances enhance muscle growth and are closely associated with testosterone, which also promotes other masculine characteristics like a deep voice and hair growth. Some anabolic hormones include:
- Growth hormone – synthesized in the pituitary gland, it stimulates the liver to produce somatomedin, leading to growth.
- IGF1 and other insulin-like growth factors – hormones that stimulate the production of protein and sulfate. IGF I and II play a role in uterine, placental, and fetal development during pregnancy.
- Insulin – produced by the pancreas’ beta cells, this hormone regulates blood sugar levels as cells require insulin to utilize glucose.
- Testosterone – primarily produced in the testes, this male hormone induces male sexual characteristics such as a deep voice, facial hair, while also enhancing muscle and bone mass.
- Estrogen – primarily produced in the ovaries, this female hormone contributes to strengthening bone mass and developing female traits like breasts.
The text explores different functions of catabolism, which include thickening the inner membrane (endometrium) of the uterus and regulating the menstrual cycle. It presents examples of catabolic processes, such as the degradation of polysaccharides (e.g., starch, glycogen, and cellulose) into monosaccharides (such as glucose, ribose, and fructose). Furthermore, it refers to another process that entails breaking down nucleic acids into nucleotides necessary for encoding genetic information and transmitting it.
Nucleic acids, such as RNA and DNA, contain purines, pyrimidines, and pentoses. These molecules provide energy for our body. Proteins undergo catabolism to break down into amino acids which can be reused or converted into other compounds. In certain instances, proteins are broken down to produce glucose in the bloodstream.”(Nordqvist). Metabolism plays a significant role in weight management but is not directly responsible for being overweight or underweight. Overweight individuals consume more calories than their body can burn while those struggling to gain weight do not consume enough calories for their body’s needs. This leads to insufficient enzyme processing in the bloodstream resulting in low energy levels. Many dietary supplements claim to increase metabolism and aid weight loss; however, relying solely on these products can be risky due to potential unwanted side effects.”Products claiming to boost metabolism often have more hype than help and may cause unwanted or even dangerous side effects.”
To achieve weight loss, a combination of exercise and diet is necessary. The key is to consume fewer calories than you expend. It can be beneficial to understand your basal metabolic rate (BMR), which determines the minimum amount of calories your body needs. Factors such as height, weight, gender, genetics, and muscle mass influence your BMR. Online BMR calculators are available to estimate your daily caloric intake accurately based on these factors. Occasionally, our metabolism may not function properly within our bodies.
A metabolic disorder is a condition that arises from abnormal chemical reactions occurring within the cells of the body. Such disorders frequently entail imbalances or problems with enzymes, hormones, and their respective activities. Disruption of the typical metabolism of chemicals in the body can result in an excess buildup of harmful substances or a shortfall of vital substances required for normal bodily processes. Certain metabolic diseases are inherited and known as inborn errors of metabolism.
If metabolic disorders are not detected and treated early in life, they can result in severe health complications or even death. Some examples of common metabolic disorders include:
- “G6PD deficiency,” a condition where there is an insufficient amount of normal G6PD to assist red blood cells in handling harmful substances, leading to potential hemolytic anemia.
- Galactosemia, a genetic disorder that causes babies to lack the enzyme needed for breaking down galactose, a sugar found in milk.
- Hyperthyroidism, which occurs when the thyroid gland is overactive.
- Hypothyroidism.
The text highlights the significance of hypothyroidism, which occurs when the thyroid gland is absent or underactive due to a developmental issue or destructive disease. It also explains that type 1 diabetes mellitus results from insufficient insulin production and release by the pancreas, while type 2 diabetes stems from the body’s inability to respond properly to insulin (Dowshen). Furthermore, it emphasizes the crucial role of metabolism in maintaining energy levels and facilitating digestion. Metabolism is essential for overall health as without it, survival would be impossible.
