Biochemistry Flashcards
(14 cards)
The difference between organic and inorganic molecules
Organic substances are comprised of complex molecules that are made by living organisms. Organic molecules contain many atoms of carbon, hydrogen, oxygen and others, e.g. nitrogen & phosphorus in various proportions. Examples of organic molecules include proteins, carbohydrates (including glucose), lipids, nucleic acids and vitamins. Cells are made up of organic molecules.
Inorganic substances include many simple compounds. They do not have long chains of carbon atoms. They can occur without being made by living organisms e.g. chemical weathering. They mostly do not contain carbon atoms e.g. water, salts, oxygen gas. When they do include carbon, they are small and simple molecules e.g. carbon dioxide.
Main functions of water in organisms
Water and metabolism:
In cells, chemical and metabolic reactions can only take place if the chemicals that are reacting are dissolved in water
Water and transport:
In animals, water forms the main component (part) of blood plasma (the liquid part of the blood). Plasma carries oxygen and nutrients like glucose to all the cells in the body.also carries away wastes like carbon dioxide and urea from all the cells in the body
Water and support:
Water is needed in plants and animals to help keep their shape and support them. In plants, cells are filled with water to keep the plant upright.
Water and cooling:
The process of evaporation has a cooling effect
Water as a habitat:
Aquatic animals and plants use sea- and freshwater environments as a habitat.
macro vs microelements
Macroelements: Calcium (Ca), Phosphorus (P), Magnesium (Mg), Sodium (Na), Potassium (K) and Chloride (Cl), the requirement is more than 100 mg/day.
Microelements: Iron (Fe), Copper (Cu), Zinc (Zn), Fluoride (F), Iodine (I), Selenium (Se) and Cobalt (Co), the requirement is from 1 to 100 mg/day.
Trace elements: Bromine (Br), Chrome (Cr), Nickel (N), Lithium (Li), Silicon (S), Tin (Sn) and others.
Calcium is a macroelement for animals name its source/s, its function and effects of a deficiency
Calcium is an example of a macroelement for humans. We get calcium from the foods that we eat. The most concentrated absorbable calcium sources are green leafy vegetables and legumes, or “greens and beans” for short.
Essential for the structure of bones and teeth.
Calcium ions are needed for blood clotting.
Plays a part in cell membrane permeability (allowing substances into and out of cells).
Plays a role in muscle contraction and the transmission of nerve impulses.
Deficiency disease: rickets in children and osteoporosis in adults.
Iron is a microelement for animals name its source/s, its function and effects of a deficiency
Iron is an example of an essential microelement for humans. We get iron from the foods we eat. The most concentrated and absorbable iron sources are from heme in meat (e.g. beef, chicken), fish and shellfish. Vegetable sources of iron are less easily absorbed and need to be eaten in the right combinations (e.g. vitamin C increases the absorption of iron).
Forms part of haemoglobin in red blood cells to carry oxygen in the blood
Deficiency disease: anaemia (a lack of red blood cells or haemoglobin)
Carbohydrates are? 1. polysaccharides 2. disaccharides 3. monosaccharids with sugar monomers
The structure of carbohydrates as polymers (polysaccharides) with sugar monomers
The food tests for glucose (1) starch (2) proteins (3)
(1.benedict’s solution) (2.iodine solution) (3. biuret solution)
lipids are (fats and oils) polymers with
1.monomers
2.polymers
of glycerol and fatty acids
The structure of lipids (fats and oils) as polymers with monomers of glycerol and fatty acids
Saturated vs Unsaturated
Saturated lipids
Saturated lipids or fats have triglycerides that include only single-bonded carbons in the fatty acid molecules and are called saturated lipids.
Unsaturated lipids
Unsaturated lipids or oils have triglycerides that contain some double-bonded carbons in the fatty acid molecules and are called unsaturated lipids.
Lipids are insoluble in water and are hydrophobic, meaning they repel water and do not mix with water. They are soluble in alcohol.
proteins as polymers with
- amino acid monomers
- amino acid polymers
- sugar monomers
The structure of proteins as polymers with amino acid monomers
The function and actions of enzymes?
Enzymes are proteins that act as biological catalysts. Catalysts speed up chemical reactions without being used up in the chemical reaction itself. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzymes in order for chemical reactions (metabolism) to occur at rates fast enough to sustain life.
Factors that influence enzyme action
Temperature
In humans, enzymes function best at 37°C. This is the optimum temperature. At very high temperatures proteins denature and the protein’s three-dimensional shape breaks down, unravelling the protein into its primary structure, a long chain of amino acids. When a protein is denatured, the shape of its active site, as well as the rest of the protein shape is altered. The substrate can no longer fit in the active site of the enzyme and chemical reactions cannot take place. Low temperatures can slow down or even inactivate enzymes..
pH
Enzyme activity is also sensitive to pH. Enzymes have an optimum pH, but they can function effectively within a pH range. The effectiveness of the enzyme falls sharply when the pH is outside its optimum range. An enzyme can become denatured when exposed to a pH outside its pH range.
Vitamin C as an example vitamin name its sources, its function and effects of a deficiency
Vitamin C
Vitamin C is also called ascorbic acid. It is found in fresh fruits and vegetables e.g. guavas and broccoli.
It helps maintain the intercellular substances (the matrix) in bones, cartilage, and dentine (teeth).
It helps to form connective tissues e.g. collagen under the skin
Deficiency disease: scurvy
Define:
monosaccharides - single saccharide
disaccharides - two saccharides
polysaccharides - many saccharides
Monosaccharides
Examples of monosaccharides include glucose, fructose and galactose. These are all different carbohydrate monomers. They are relatively small molecules and are soluble in water. They have a sweet taste.
Disaccharides
Disaccharides are made up of two saccharide monomers bonded together. Examples include sucrose (glucose + fructose), maltose (glucose + glucose) and lactose (glucose + galactose). They are also soluble in water and also taste sweet.
Polysaccharides
Polysaccharides are made up of many saccharide monomers bonded together. Examples include starch (plants), glycogen (animals) and cellulose (plants). They are not soluble in water and are tasteless (i.e. not sweet).
Importance:
Carbohydrates are important as a source of energy in living organisms, especially glucose. Carbohydrates store chemical potential energy (fuel) as starch in plants and glycogen in animals. Some carbohydrates, e.g. cellulose, form the cell walls in plants and therefore give it structure.
