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Week 4 By: Andrews and Edmond. [image].

[image] Welcome.

[image]. [image] EXPER"AENTS- O ST RAT ION S _ & M ORE.

[image]. In our previous lesson, ended our discussion on Chemical bonds..

Today we shall be looking at: Enzymes.

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TOPIC: Enzymes SUB-TOPIC: Enzyme action OBJECTIVE: by the end of the lesson, the pupil will be able to:.

[image] , ENZYMES .O The workers in our body.

[image] What are Enzymes? • Enzymes are proteins which act as biological catalysts. — A catalyst is a substance that starts or speeds up a chemical reaction. — It lowers the activation energy required for the reaction to take place. • Enzymes are used by cells to trigger and control chemical reactions. • Without enzymes, several reactions in cells would never occur or happen too slowly to be useful..

[image] 1. What are enzymes? Enzyme • Enzyme band to snate Free enzyme • What are enzymes (short video clip) 1. Enzymes are found in all living cells. 2. Enzymes are made of protein. 3. Enzymes are Biological Catalysts 4. Enzymes speed up reactions 5. Enzymes are unchanged by the reaction.

[image] WHAT ARE ENZYMES? They are biological catalysts. o A catalyst is a chemical that can speed up chemical o reactions without being changed or used up. They are molecules made of protein that have a certain o shape "dent" to attach to a certain molecule. O o O.

[image] The molecule to which an enzyme attaches is o called a substrate. The site of attachment is called the active site o The molecule(s) resulting from the catalytic reaction o is named the product(s). The theory developed to explain how enzymes o work is called the key and lock theory. O O Enzyme-substrate complex.

[image] ENZYME PROPERTIES o o o o o o o Enzymes are made of proteins. They are "specific"= they can only work on one type of molecule. Their activity is affected by changes in temperature. Their activity is a affected by changes in PH. Every enzyme has a temperature at which it works best; it is called the optimum temperature. Every enzyme has a pH at which it works best; it is called the optimum PH. The enzyme would not be active if its active site is permanently changed, we say it is denatured. O.

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[image] EFFECT OF TEMPERATURE temperature As the temperature o increases, molecules gain more kinetic energy and move faster. Bumping into each other more often, this speeds up the reaction. But if the temp rises above the optimum the enzyme's shape changes and it no longer works; it is now O denatured..

[image] EFFECT OF pH If the solution where o enzymes work becomes more acidic or more basic this changes the lengths of the bonds holding it in that special shape. The farther away from the optimum pH the more the change in the enzyme's shape. It is also denatured by extreme changes in PH..

[image] EFFECT OF ENZYME CONCENTRATION As the concentration of o enzymes increase more active sites are available to speed up the reaction. enzyme.

[image] EFFECT OF SUBSTRATE CONCENTRATION o o substrate As the concentration of substrate increases the chance of a substrate bumping into the enzyme increases. This speeds up the reaction. After a certain concentration; adding more substrate doesn't speed up the reaction. O.

[image] EFFECT OF SURFACE AREA If both of these cells o had digestive enzymes on their cell membrane to digest food that has reached the small intestine. Which of these cells will the enzymes finish their job faster?.

[image] time As the reaction proceeds the amount of substrate decreases while the amount of product increases. This continues till the reaction stops. O.

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Summary; Today, we learnt that;. [image] • • • Enzymes are specialized proteins that act as catalysts; they speed up chemical reactions by lowering the activation energy required. Enzymes are NOT used up during a reaction. Enzymes are specific to a particular substrate (reactant)..

[image] How do enzymes work? Each enzyme has a unique 3-D shape. including a surface groove called The enzyme works by binding a specific chemical reactant (—) to its active site. causirv the substrate to become unstable and react. The resulting (a) Reaction (s) is then released from the active site. products.

Week 4 By: Mr. Andrews Aabesagr. [image].

[image] Welcome.

[image]. [image] EXPER"AENTS- O ST RAT ION S _ & M ORE.

[image]. In our previous lesson, we started looking at enzymes.

Today we shall continue our talk on: Enzymes.

[image] Psalm 27:1 The LORD my light ana my dalpation- whom dhall I fear? The LORD id the dtrongbolå of my life- of whom dhall I be afraD?.

TOPIC: Enzymes SUB-TOPIC: Enzyme action OBJECTIVE: by the end of the lesson, the pupil will be able to:.

[image] Enzymes in Germination.

[image] The seed contains the embryo plant and cotyledons (starch stores) Testa Plumule (embryo shoot) Radicle (embryo root) Micropyle Water enters the seed through the micropyle and activates enzymes. The water also softens the testa to allow it to split. Cotyledon.

[image] Enzymes are used in seed germination Plumule embryo plan Radicle This is the first part to grow out of the seed as it needs to absorb more water starch secreted maltose The enzymes break starch down into maltose and then glucose. The glucose is used in respiration to provide energy for growth.

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[image] Enzymes aid in germination • Seeds imbibe water and swell. The testa softens and splits. • Enzymes are activated and the following reactions take place in the cotyledon where food is stored. • Starch is broken down to Glucose by Amylase and Maltase.( energy for growth and making cell wall).

[image] Enzymes aid in germination • Insoluble products are converted to soluble forms to facilitate uptake by the growing seedling. • Proteins are broken down to Amino Acids by Proteases(cell membranes, cytoplasm and cell organelles). • Any Lipids are broken down to Fatty Acids and Glycerol by Lipase..

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