Biology Test

Front 1

Nucleic acid

Back 1

DNA: Nucleic acids are composed of DNA and RNA they are chemicals used to create genes. They are biopolymers. A polymer is a large molecule, or macromolecule, composed of many repeated subunits and biopolymer just means that it is produced by a living organism.

Front 2

proteins

Back 2

Proteins: are varied in structure and carry out a wide range of tasks including controlling chemical reactions of the cell by acting as enzymes

DNA and Proteins are the most complex molecules

Front 3

Synthesis of Urea

Back 3

Urea is a compound produced by living organisms but can also be artificially synthesized

Front 4

Carbon 1

Back 4

Carbon atoms can form four bonds which allows a diverse compound existence.

15th most abundant element on earth.

Carbon is used to make a huge range of different molecules.

The diversity of carbon compounds is explained by the properties of carbon.

Front 5

Carbon 2

Back 5

Carbon atoms form covalent bonds with other atoms. Covalent bonds are formed when two adjacent "close to" atoms share a pair of electrons.

Each carbon atom can form up to four covalent bonds, which is more than most atoms.

Fatty acids contain chains up to 20 carbon atoms.

Front 6

Classifying carbon compounds 1

Back 6

Life is based on carbon compounds including carbohydrates, lipids, proteins and nucleic acid.

Four main classes of carbon compounds are used by living organisms.

Carbohydrates: characterized by their composition. Composed by carbon, hydrogen and oxygen. 2 hydrogen atoms to 1 oxygen

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Classifying carbon compounds 2

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Lipids: Broad range of molecules that are non-dissolvable in water ( including steroids, waxes, fatty acids and triglycerides.

Proteins: composed of one or more chains of amino acids. All amino acids in these chains contains the elements carbon, hydrogen, oxygen and nitrogen. Two of the amino acids also contain sulphur.

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Classifying carbon compounds 3

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Nucleic acids: are chains of subunits of nucleotides, which contain carbon, hydrogen, oxygen, nitrogen and phosphorus.

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Anabolism and Catabolism 1

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Anabolism is powered by catabolism, where large molecules are broken down into smaller parts and then used up in respiration.

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Anabolism and Catabolism 2

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Anabolism includes these processes:

Protein synthesis using ribosomes.

DNA synthesis during replication.

Photosynthesis (including production of glucose from carbon dioxide and water.)

Synthesis of complex carbohydrates including starch, cellulose and glycogen.

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Anabolism and Catabolism 3

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Catabolism: The breakdown of complex molecules into simpler molecules including the hydrolysis of macromolecules into monomers.

Catabolic reactions release energy and in some cases this energy is captured in the form of ATP "Adenosine Tri Phosphate" which can then be used in the cell.

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Anabolism and Catabolism 4

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Catabolism includes these processes:Digestion of food in the mouth, stomach and small intestine.Cell respiration in which glucose or lipids are oxidized to carbon dioxid and water.Digestion of complex carbon compounds.

Front 13

Monosaccharides, Disaccharides and Polysaccarides (Carbohydrates) 1

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Monosaccharide monomers (molecules) are linked together by condensation reactions to form disaccharides and polysaccharides polymers. This process is called anabolic process.

Monosaccharides combine by condensation. examples : Glucose, fructose and ribose

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Monosaccharides, Disaccharides and Polysaccarides (Carbohydrates) 2

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Monosaccharides are single sugar units.

Disaccharides consist of two monosaccharides linked together.

e.g maltose is made linking two glucose molecules together. Polysaccharides consist of many monosaccs. E.g starch, glycogen and cellulose are polysaccs. Polysaccharides: "Humans= Glycogen" "Plants=Cellulose"

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Hydrogen bonding in water 1

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Water molecules are polar and hydrogen bonds form between them. The attraction between water molecules is a "hydrogen bond."

Hydrogen bonds are a weak intermolecular force. A water molecule is formed by covalent bonds between oxygen atom and two hydrogen atoms.

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Hydrogen bonding in water 2

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An equal sharing of electrons in water molecules that leads to hydrogen atoms having a partial positive charge and oxygen has a partial negative charge.

Positive charged particles (positive ions) and negatively charged particles (negative ions) form ionic bonds.

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Properties of Water 1

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Cohesive:

The binding of two molecules of the same type for instance two water molecules.

Water molecules cohere due to hydrogen bonding. This is useful for water transportation in plants.

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Properties of Water 2

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Adhesive: Attraction with different molecules. Hydrogen bonds can form between water and other polar molecules, causing water to stick to them. e.g water on glass.Useful in leaves where water adheres to cellulose molecules in cell walls.

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Properties of Water 3

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Thermal Properties:

High specific heat properties: High amount of energy needed to raise temperature of water, the same with cooling it down.High latent heat of vaporization: When a molecule evaporates it separates from other molecules in a liquid and becomes a vapor.Large amount of heat is needed for water to evaporate since hydrogen bonds need to be broken. A good evaporative cooler e.g sweating.

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Properties of Water 4

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One of the best solvents:

The polar nature of water molecules leads to it forming shells around the charged and polar molecules which prevents them from clumping together and instead keeps the solution.

Front 21

Hydrophilic and hydrophobic 1

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Substances can be hydrophilic or hydrophobic:

Substances that dissolve in water are hydrophilic and substances that adhere to (cellulose e.g) are also hydrophilic.

some substances are insolvable in water although they dissolve in there substances such are called hydrophobic.

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Hydrophilic and hydrophobic 2

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all lipids are hydrophobicthe forces that cause non polar molecules to join together into groups in water are known as hydrophobic interactions

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Different Proteins 1

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Blood clotting: Plasma proteins act as clotting factors that cause blood to turn from a liquid to get into wounds

Transport of nutrients and gases: Proteins in blood help transport oxygen carbon dioxide, iron and lipids.

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Different Proteins 2

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Cell adhesion: Membrane proteins cause adjacent animal cells to stick to each other within tissues.Membrane transport: Membrane proteins are used for facilitated diffusion and active transport, and also for electron transport during cell respiration and photosynthesis. Hormones: Some such as insulin, FSH and LIT are proteins, but hormones are chemically very diverse.Receptors: binding sites in membranes and cytoplasm for hormones neurotransmitters, tastes and smells, and also for light in the eye and in plants.

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Different Proteins 3

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Packing of DNA:

Histones are associated with DNA in eukaryotes to condense during mitosis.Immunity: This is the most diverse group of proteins and cells can make huge numbers of different antibodies.