Module 1

Question 1

What are nutrients

Answer 1

Substances needed by the organism for assembly of structural components, provision of energy and optimal function of the biochemical machinery

Question 2

What are macronutrients

Answer 2

Substances that are required in large amounts

Question 3

What are micronutrients

Answer 3

Substances that are required in trace amounts

Question 4

Give examples of macronutrients

Answer 4

Carbs, proteins and fats

Question 5

Give examples of micronutrient

Answer 5

Minerals and vitamins

Question 6

What are the elemental composition of life and give an example

Answer 6

• highly abundant
  Ex: carbon, hydrogen, oxygen, nitrogen

-small amounts
Ex: calcium, potassium, iron, sodium

• detectable
  Ex: boron, bromine, tin

Question 7

What are the 2 things absolutely necessary for life

Answer 7

Energy ( light, heat, chemical) and raw materials ( carbon source, water, oxygen)

Question 8

What are the polymers of carbs, proteins, nucleus acid and lipids

Answer 8

Carbs - polymers of simple sugars
Protein- polymers of amino acids
Nucleic acid- polymers of deoxyribonucleic acids
Lipids - no polymers

Question 9

Explain why metabolism is anabolism and catabolism

Answer 9

Metabolism used nutrients as substrates to facilitate the assembly of high order structures and maintenance of life. So the metabolism destroys the food that we eat ( catabolism) and we absorb the nutrients and then the nutrients are put together to build blocks ( anabolism)

Question 10

Life used raw materials for what?

Answer 10

Construction of strife, development and propagation of genetic material

Question 11

Nutrients are bioactives. What do they do

Answer 11

1)components of cellular structures
2) substrates for energy production
3) regulates of cellular activity

Question 12

True or false
Does gene control the metabolism of nutrients

Answer 12

True

Question 13

What does it mean when the gene is repressed

Answer 13

It means that they are not completely turned off but they have very low basal activity

Question 14

Explains lac operon of E.Coli

Answer 14

So lac I : encodes a repressor
There is 1 promoter that encodes 3 genes
The operator is not functional if it is not bind to the repressor. When the repressor binds t the operator it prevents the transcription of these genes

Question 15

What sugars make lactose and what enzyme is responsible to break lactose

Answer 15

Galactose and glucose. B-galactosidase breaks lactose

Question 16

Explain the metabolism of lactose in the mammalian gut

Answer 16

Someone ingest lactose, it will go to the small intestine where digestion will take place. In the small intestine is where lactose is present if someone doesn’t have enough, the bacteria in the colon will use the lactose and make glucose and galactose. The bacteria will cause a fermentation and it will produce gas

Question 17

Explain how the lactose regulates the E.Coli lac operon

Answer 17

When there is not a lot lactose, the repressor will bind to the operator and it will block gene expression.

When there is a lot of lactose, the lac permease (LacY) is a channel that will let lactose come inside the cell. When there is a lot of lactose, the repressor will bind to the lactose instead of binding to the operator and so the promoter can activate the expression of the genes

Question 18

Explains how cholesterol regulates the processing and activity of transcription factor SREBP

Answer 18

In low cholesterol concentration the SREBP and the other constitutes will migrate from the ER to the Golgi and by proteolytic cleavage it will release SREBP. SREBP will go to the nucleus and bind to the SRE ( sterial response element) and this will stimulate the expression of cholesterol synthesis and fatty acid biosynthesis. The cholesterol will bind to the structure in the membrane and INSIG will come along and make them stay together.

The presence of cholesterol will inactivate the system. And when it is not present it will activate in order to make more cholesterol

Question 19

Regulation of gene expression by nutrients

Answer 19

Nutrients can affect gene expression in different areas. It can affect the translation, the transduction, transcription and even when the protein is already done iron can affect

Question 20

Explain the regulation of protein and lipid biosynthesis

Answer 20

Nutrients affect MTORC1 which affects the increases proteins in the cell. And MTORC 1 also affect STRBP which increase synthesis of lipids

Growth factors can also increase protein and lipids

Cellular energy inhibits proteins and lipids biosynthesis

Question 21

Tell if this will increase or decrease protein and lipids biosynthesis
1. Grow factor
2. Nutrients
3. Cellular energy status

Answer 21

1 and 2 : increase
3. Decrease