What Happes In Cells

Question 1

How does the sequence of DNA affect the protein made in protein synthesis?

Answer 1

DNA is a triplet code where 3 bases code for one amino acid and the order of amino acids determine the protein
produced

Question 2

Enzymes

Answer 2

Enzymes are biological catalysts that speed up the rate of metabolic reactions

Question 3

Enzyme structure

Answer 3

Enzymes are proteins that contain an active site that fits a specific substrate

Question 4

Lock and key hypothesis

Answer 4

The idea that only a specific substrate fits the specific active site of the enzyme, and only then a reaction occurs.

Question 5

Affect enzymes

Answer 5

• Temperature
• рН
• Substrate concentration
• Enzyme concentration

Question 6

Describe the effect of temperature on the rate of an
enzyme-controlled reaction

Answer 6

As the temperature increases, so does the rate of reaction
- Once the temperature exceeds the optimum, the enzyme denatures and the rate of reaction decreases

Question 7

What is the function of MRNA and DNA in protein synthesis

Answer 7

• the dna is contains the genetic code that codes for the function of an organism, and this code is needed to code for the correct amino acids during protein synthesis. However, the dna is too large to fir through the nucleus, so mRNA is used to complement the genetic code and then travels to the ribosome where translation can then take place

Question 8

What is the function of TRNA in protein synthesis

Answer 8

When the mrna reaches the ribosomes, the complemented code is read by the ribosome, and arranged in to groups of three called triplet code or condons. These codons code for the amino acid that needs to be used. The TRNA is what brings the amino acid to the correct codon that codes for it

Question 9

What are the 4 bases

Answer 9

Adenine, thymine, guanine, cytosine

Question 10

What bases bond together

Answer 10

Adenine <—> thymine
Guanine <—> cytosine

Question 11

DNA

Answer 11

DNA is made up of two linked strands that wind around each other to form a double helix it is made up of lots of small units called nucleotides DNA is a polymer. Nucleotides are made up of sugars, phosphate and a base and are held together by hydrogen bonds between them. There are four such found in DNA: adenine, thymine, guanine and cytosine

Question 12

What is DNA 6 MARK answer

Answer 12

DNA is genetic code that could for the function of every cell in an organism. DNA is found in both multicellular and unicellular organisms and is made up of two linked strands that wind around each other to form a double helix. It is made of lots of small units called nucleotides. This means that DNA is a polymer. Every nucleotide is made up of a sugar, phosphate and a base and are held together by hydrogen bonds between the two complementary bases . There are four bases found in DNA: adenine, thymine, guanine and cytosine. In DNA, adenine always pairs and binds with thymine, and guanine binds and pairs with cytosine

Question 13

What are enzymes (long answer)

Answer 13

Enzymes are biological catalysts. This means that they can speed up reactions without being used up themselves. Enzymes are highly specific. This means that they only bond with a certain substrate which fits in their active site. The active site is a place in the enzyme where the substrate can fit with it. This is called the lock and key theory if the enzymes active site is changed or denatured, to be reaction slowing down or reaction may not take place at all. there are many factors that can affect the rate of enzyme reaction and affect the shape of the active site. They are: temperature, pH, concentration of enzyme and concentration of substrate. By increasing all of these factors you can speed up the reaction however if these factors are increased beyond a certain point the enzyme will start to denature and lose its shape. This will result in the reaction slowing down and eventually stopping due to the shape of the active site and the substrate no longer fitting. Enzyme has an optimum temperature for example in our bodies the enzymes have an optimum temperature of around 36° which is our body temperature anything above or below this temperature could result in them and slowing down the chemical reactions we need for our body to survive.

Question 14

How to test for proteins

Answer 14

Place two spatulas of the food sample into a test tube or 1 cm3 if the sample is liquid. Add about 1 cm3 depth of water to the tube and stir to mix.
Add an equal volume of Benedict’s solution and mix.
Place the tube in a water bath at about 95°C for a few minutes.

Question 15

Test for proteins

Answer 15

Mash up substance, add it to beaker, add buirets solution and wait for reaction

Question 16

Test for sugars

Answer 16

Mash up item, add sample to boiling tube with a few drops of Benedict’s solution. Heat the mixture in a water bath and observe the reaction.

Question 17

Test for fats

Answer 17

Mash up substance, mix your substance and water and stir vigorously, add in one to two drops of ethanol and twist for reaction to take place