Aim: How do enzymes work?

Aim: How do enzymes work? Enzymes are a particular kind of protein that have the ability to catalyze reactions in living organisms. Proteins are very long chain molecules made up of amino acid building blocks. The protein chain is folded in a complex three dimensional shape known as its tertiary structure. Work with your group and write everything you know about amino acids. There are 20 amino acids. They differ by what is on the central carbon. All amino acids contain a N atom in the chemical formula. Amino acids come into our body as food that we eat. Proteins are made up of amino acids. Twenty amino acids arrange.

What do you know about amino acids? Group work - 1 minute http://www.hcc.mnscu.edu/programs/dept/chem/V.27/amino_acid_structure_2.jpg How many proteins can you make with 20 amino acids? Activity: Let students use numbers to represent amino acids. Let students make a chain of numbers in any arrangement, any length so they get the idea that there can be thousands of different chemical proteins.

They differ by what is on the central carbon. There are 20 amino acids. They differ by what is on the central carbon. All amino acids contain a N atom in the chemical formula. Amino acids come into our body as food that we eat. Proteins are made up of amino acids. Twenty amino acids arranged in an endless array yields an infinite number of proteins. Digestive enzymes are proteins

The Digestive Enzymes Mouth Stomach Small intestine (from pancreas) Section 38-2 Site Mouth Stomach Small intestine (from pancreas) Small intestine Enzyme Role in Digestion Salivary amylase Pepsin Amylase Trypsin Lipase Maltase, sucrase, lactase Peptidase Breaks down starches into disaccharides Breaks down proteins into large peptides Continues the breakdown of starch Continues the breakdown of protein Breaks down fat Breaks down remaining disaccharides into monosaccharides Breaks down dipeptides into amino acids. Discuss conditions of pH and temperature

ENZYMES There are more than 3,000 known enzymes in the human body. The body’s ability to function and repair itself is directly related to the strength and number of enzymes that are present. Every second, they are changing and renewing, sometimes at unbelievable rates. The function of enzymes – promote chemical reaction by breaking bonds or putting bonds in place.

The enzyme shape fits the shape of the substance it will break down. Because enzymes are proteins and there made up of many (100’s) of amino acids they chain can fold on itself to form a particular shape. The enzyme lipase catalyses the breakdown of fatty acids. Proteins have a three dimensional shape.

Enzymes work in specific ways Substrate is what will be digested (broken down) by the specific enzyme Activity: students will make an enzyme. Make parts so that they fit. Each groups enzymes will not fit another groups substrate. Example: enzyme is lipase, substrate is fat

Enzyme action The enzyme and substrate come together at the active site. The shape of the enzyme fits the shape of the substrate

Digestive enzymes ..break down larger molecules into smaller ones

Products are … ..different from what we started with Go to internet site

Real life application of enzymes Many biological washing powders contain enzymes to help with the removal of stains. The enzyme may be a protease to break down protein stains or a lipase to break down fat and oil (lipids) stains.

Digestion of starch Starch is a much larger molecule. Digestion breaks the bonds between the units.

Salivary Amylase This enzyme breaks the bonds that hold the polymer together

Digestion of starch produces simple sugars

Enzymes are proteins Enzymes are needed for synthesis also.

Protease digests proteins All enzymes have a particular shape that fits the molecules they act on.