Introduction to Biochemistry: Definition, Scope, History, and Key Biomolecules

Summary

This lecture introduces biochemistry as the study of life's chemical processes at the molecular level, covering the history, development, and key biomolecules. It highlights the importance of proteins, nucleic acids, lipids, and carbohydrates, their structures, and functions in living organisms. The script also touches on the significance of biochemistry in healthcare, nutrition, genetics, and environmental science, emphasizing its role in diagnosing diseases and developing personalized medicine.

Takeaways

• 🔍 Biochemistry is the study of life's chemical reactions and processes within and relating to living organisms.
• 📚 The term 'biochemistry' was coined by Carl Neuberg in 1903, emphasizing the chemical reactions in life.
• 🌿 Biochemistry covers more than humans; it includes the study of animals, plants, and their chemical processes at the molecular level.
• 🧬 The four main biomolecules studied in biochemistry are proteins, nucleic acids, carbohydrates, and lipids.
• 🕰 A brief history of biochemistry includes ancient practices and the significant contributions from various scientists across centuries.
• 🏆 Emil Fischer was awarded the Nobel Prize in 1902 for his work on the structure of proteins and enzymes.
• 🧬 Nucleic acids are crucial for the storage and transmission of genetic information and protein synthesis.
• 🥚 Proteins serve various functions, including structural support, catalysis of biochemical reactions, and immune response.
• 🍬 Carbohydrates are the body's primary energy source, with glucose being a common monosaccharide.
• 🥑 Lipids function as energy storage, provide insulation, and are integral to cell membranes, with different types including saturated and unsaturated fats.
• 🧪 Biochemistry is vital in healthcare for diagnosing and treating diseases, as well as in nutrition, genetics, and environmental science.

Q & A

What is the definition of biochemistry?

Biochemistry is defined as the study of life's chemical reactions, or alternatively, the study of chemical processes within and relating to living organisms.

What are the four main biomolecules studied in biochemistry?

The four main biomolecules studied in biochemistry are proteins, nucleic acids, carbohydrates, and lipids.

How does the history of biochemistry date back to ancient times?

The history of biochemistry dates back to ancient times as ancient Egyptians, Chinese, and Greeks used biochemistry in making herbal medicines, although they did not understand the underlying processes.

Who is considered the father of modern chemistry and what was his contribution to biochemistry?

Anton Lavoisier is considered the father of modern chemistry. He identified the role of oxygen in combustion and respiration, which laid the foundation for the understanding of metabolism.

What significant event in the 19th century challenged the vitalism theory?

In the 19th century, Friedrich Wöhler synthesized urea from ammonium cyanate, challenging the vitalism theory that organic compounds cannot be made from inorganic ones.

Who coined the term 'biochemistry' and when?

Carl Neuberg coined the term 'biochemistry' in 1903, defining it as the chemistry of life and the chemical reactions happening in our lives.

What is the primary function of carbohydrates in living organisms?

The primary function of carbohydrates is to store energy and serve as the body's main energy source.

What are the building blocks of proteins and what role do they play in the body?

The building blocks of proteins are amino acids. Proteins play various roles in the body, including providing structural support, catalyzing biochemical reactions as enzymes, transporting molecules, and participating in immune responses.

What are the differences between the structures of saturated and unsaturated lipids?

Saturated lipids have no double bonds in their fatty acid chains and are typically solid at room temperature, while unsaturated lipids have one or more double bonds, making them liquid at room temperature.

What are the functions of nucleic acids and what are their building blocks?

Nucleic acids function in the storage and transmission of genetic information, and in protein synthesis. Their building blocks are nucleotides, composed of a sugar, phosphate group, and a nitrogenous base.

How do biomolecules serve as markers in various medical tests?

Biomolecules serve as markers in medical tests by indicating the presence of certain conditions. For example, C-reactive proteins can indicate inflammatory diseases, PCR testing uses nucleic acids to detect genetic mutations, and lipid profile tests can reveal conditions like atherosclerosis.

Outlines

00:00

🧬 Introduction to Biochemistry

This paragraph introduces the field of biochemistry, defining it as the study of life's chemical reactions and chemical processes within living organisms. It outlines the learning objectives, which include understanding the definition of biochemistry, its history, the four main biomolecules (proteins, nucleic acids, carbohydrates, and lipids), and their functions in biological systems. The historical development of biochemistry is traced from ancient civilizations to modern advancements, including the work of key scientists and the emergence of genetic engineering and the Human Genome Project.

05:04

🍬 Biochemistry of Carbohydrates and Lipids

This section delves into the role and structure of carbohydrates and lipids in biochemistry. Carbohydrates, the body's primary energy source, are described in terms of their monosaccharide building blocks, disaccharides, and polysaccharides like starch and glycogen. The importance of lipids, including fats, is highlighted, with a focus on their functions in energy storage, insulation, and as components of cell membranes. The distinction between saturated and unsaturated fats, and their health implications, is also discussed.

10:05

🥚 Proteins: Structure and Function

Proteins are explored in this paragraph as essential biomolecules with roles in structural support, catalysis, transport, communication, and immune response. The composition of proteins, including their elements and amino acid building blocks, is detailed. The structure of proteins, from primary to quaternary, is explained, with examples such as hemoglobin and the significance of peptide bonds. The importance of protein folding and the variety of amino acids, including essential and nonessential types, are also covered.

15:06

🧬 Nucleic Acids: Genetic Material and Beyond

The final paragraph focuses on nucleic acids, the carriers of genetic information within cells. Their function in heredity, protein synthesis, and as the building blocks of DNA and RNA is explained. The structure of nucleic acids, composed of nucleotides with sugar, phosphate, and nitrogen bases, is described. The differences between DNA and RNA, particularly in their nitrogen bases, are highlighted. Additionally, the role of ATP as the energy currency of the cell is briefly mentioned.

Keywords

💡Biochemistry

Biochemistry is the central theme of the video, defined as the study of life's chemical reactions or chemical processes within and relating to living organisms. It encompasses the molecular understanding of life, including the study of biomolecules and their functions. The script uses the term to introduce the subject and discusses its history and development, highlighting its importance in various fields.

💡Biomolecules

Biomolecules are the fundamental units discussed in the script, including proteins, nucleic acids, lipids, and carbohydrates. They are essential for various biological functions and are the focus of biochemical study. The video script mentions these molecules in the context of their roles in the body and their significance in biochemistry.

💡Proteins

Proteins are large biomolecules composed of amino acids and are vital for structural support, catalyzing biochemical reactions, transporting molecules, and facilitating communication between cells. The script explains that proteins are essential for building muscle and are an example of how biochemistry relates to everyday life, such as in the context of gym-goers consuming protein.

💡Nucleic Acids

Nucleic acids, such as DNA and RNA, are the genetic material of living organisms, responsible for storing and transmitting genetic information and facilitating protein synthesis. The script describes the structure of nucleic acids and their importance in heredity and cellular processes, emphasizing their role in biochemistry.

💡Lipids

Lipids, including fats, are biomolecules that serve as energy storage, provide insulation, and are integral to cell membrane structure. The script differentiates between saturated and unsaturated fats, discussing their dietary sources and the health implications of consuming different types of lipids.

💡Carbohydrates

Carbohydrates are the body's primary energy source, consisting of sugars derived from food. The script explains the different types of carbohydrates, such as monosaccharides, disaccharides, and polysaccharides, and their role in energy storage and providing quick energy for the body.

💡Enzymes

Enzymes are a type of protein that catalyze biochemical reactions, facilitating various metabolic processes. The script mentions enzymes as an example of proteins' function in biochemistry, highlighting their importance in the chemical reactions that sustain life.

💡Metabolism

Metabolism refers to the set of life-sustaining chemical reactions in organisms. The script mentions Anton Lavoisier's contribution to the understanding of metabolism by identifying the role of oxygen in combustion and respiration, thus linking biochemistry to the broader concept of metabolic processes.

💡Vitalism Theory

The vitalism theory, which the script briefly mentions, is an outdated belief that organic compounds cannot be synthesized from inorganic substances. The script uses the historical context of this theory to illustrate the progress of biochemistry and the overturning of such beliefs with the synthesis of urea by Friedrich Wöhler.

💡Genetic Engineering

Genetic engineering is a technique in biochemistry that allows for the manipulation of an organism's genes. The script refers to the late 20th-century development of genetic engineering and its role in advancing the field of biochemistry, including the Human Genome Project.

💡PCR Testing

PCR (Polymerase Chain Reaction) testing is a molecular biology technique used to amplify a single copy or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence. The script mentions PCR testing as an application of nucleic acids in detecting genetic mutations and variations.

Highlights

Introduction to biochemistry, defining it as the study of life's chemical reactions.

Biochemistry's scope includes animals, plants, and is not limited to human beings.

Historical roots of biochemistry dating back to ancient civilizations and alchemists.

Anton Lavoisier's contribution to metabolism by identifying oxygen's role in combustion and respiration.

19th-century advancements with Friedrich Wöhler's synthesis of urea, challenging vitalism theory.

Louis Pasteur's demonstration that fermentation is a process carried out by living organisms.

Eduard Buchner's discovery of cell-free fermentation using yeast.

Harden and Young's elucidation of the biochemical pathway for alcoholic fermentation.

Emil Fischer's Nobel Prize-winning work on protein and enzyme structures.

Carl Neuberg's coining of the term 'biochemistry' and proposing a chemical pathway for fermentation.

Development of genetic engineering and the Human Genome Project in the late 20th century.

Biochemistry's practical applications in healthcare, diagnostics, and personalized medicine.

Role of carbohydrates as the body's primary energy source and their structure from monosaccharides to polysaccharides.

Lipids as energy storage, their types, and their importance in cell membranes and insulation.

Proteins' functions in structural support, catalysis, transport, communication, and immune response.

Amino acids as the building blocks of proteins, with 20 types including essential and nonessential.

Nucleic acids' role in genetic information storage, transmission, and protein synthesis.

Nucleotides, the building blocks of nucleic acids, composed of a sugar, phosphate, and nitrogen base.

Transcripts

hi everyone so today we're going to have

the introduction to biochemistry here

are your learning targets at the end of

the lecture you should be able to Define

what biochemistry is identify the key

events in the history and development of

biochemistry describe the biological

molecules distinguish the basic

structure of proteins nucleic acids

lipids and carbohydrates and finally

identify the general functions of

biomolecules and cells including their

structural and functional roles so what

is biochemistry if we're going to

dissect the word biochemistry we're

going to have two words first is bio and

chemistry bio means life that's why we

have biology the study of life and

chemistry is the science of matter and

its interactions or chemical reactions

therefore we can Define biochemistry as

the study of life's chemical reactions

now other books would Define

biochemistry as the study of chemical

processes within and relating to living

organisms now take note living organisms

doesn't say human beings biochemistry

includes or covers animals and plants

basically we can say that biochemistry

is the study of Life at the molecular

level now in Biochemistry we're going to

study four

biomolecules namely the proteins the

nucleic acids the carbohydrates and the

lipids so here we're just going to have

an overview and in the next video we're

going to study them one by one before

anything else let's have a brief history

biochemisty is not entirely new okay it

started way back in ancient history

ancient Egyptians used biochemistry in

making te the same goes in the ancient

Chinese and this one is the ancient

Greek so they've been using biochemistry

to make herbal medicines but they don't

know or they don't understand the

processes now now in the Middle Ages

there have been Alchemists who started

doing experiments in this picture you

will see an alchemist doing a

distillation experiment in the 14th

century there were advancements in

anatomy And phology scientists named

paracelsus introduced idea that disease

could be the result of chemical

imbalances in the body then in the 18th

century Anton Laos was named as the

father of Modern Chemistry or actually

it's just lately but yeah lavas say

identified the role of oxygen in

combustion and respiration so this laid

the foundation for metabolism now in the

19th century Fredick Waller was able to

synthesize urea from ammonium cyanate

this one challenge the vitalism theory

the vitalism theory states that organic

compounds cannot be made from inorganic

ones then we have Louie pasture who

demonstrates ated that fermentation and

metabolic processes are carried out by

living organisms in 1987 Edward Buckner

was able to discover cellfree

fermentation so here he used yeast in

the 20th century Harden and yang

elucidated the biochemical pathway for

alcoholic fermentation and then in early

1900s the discovery of vitamins and then

1902 Emil Fischer was awarded the Nobel

Prize for his work on the structure of

proteins and enzymes okay so later we're

going to see the structure of proteins

and then very important 1903 Carl

Newberg coined the term biochemistry he

said that biochemistry is the chemistry

of life the chemical reactions happening

in our lives in 1912 he proposed a

chemical pathway for fermentation and in

1913 the nor M Elis and M menen

published a paper describing the

properties of enzyme catalyzed reactions

so this one gave birth to the melis

Menon equation which we will discuss

soon now here in the late 20th century

the development of genetic engineering

to place then we have the Human Genome

Project then we have the Human Genome

Project and then up until the present

advancement in metabolomics and

proteomics again we said that

biochemistry she studies the chemical

reactions at the molecular level but

biomolecules they don't only work at the

molecular level or they don't just do

their work at the molecular level they

are also

markers okay for example proteins

proteins are used in C reactive proteins

test so this one will show the

inflammatory diseases for example if

your test is high it could mean you have

inflamed joints or organs so one example

would be arthritis or lupus nolic acids

are used in PCR testing polymerase Chain

Reaction testing okay so this one tests

genetic mutations and variations and I'm

sure you know this picture it's the

covid-19 virus right and then we have

the carbohydrates used in blood sugar

testing detect your glucose level or the

sugar level in your body and then we

have lipids we have the lipid profile

test so it could detect let's say

atherosclerosis atherosclerosis is the

deposition of fats in your veins which

could lead to heart attacks so the

question is why biochemistry why is it

important as mentioned it is important

in healthcare in diagnosing and treating

diseases nutrition promotes health and

well-being genetics we have now the

personalized medicines right

Pharmaceuticals related to healthcare

biochemistry is used in drug development

a nasty environment using biochemistry

we can see the contamination levels of

the soil now let's talk about the

different

biomolecules let's start with

carbohydrates carbohydrates these are

your sugars here in the nutrition facts

you will see that total carbohydrates 4

to6 gram then you have dietary fiber

these are the carbohydrates that will

help in digestion and you will also see

sugars so you have 2 G added sugar

that's from your carbohydrates the main

function of your carbohydrate is to

store energy okay it is the body's

energy source and carbohydrates are the

most common organic compound so since

it's an organic compound the elements

present are usually carbon hydrogen and

oxygen and they are in 1 is to 2 is to

one ratio remember this that's why they

are called carboh hydrates carbon

hydrates meaning water hydrates of

carbon so the building block are the

monosaccharides so these is your monomer

the prefix means one so one example or

the most common example would be glucose

now if you join different monomers if

you add different monomers you'll have

your polymer and the polymer is called a

polysaccharide poly meaning many

examples include starch glycogen

cellulose kene okay so carbohydrates

they came mostly from the food we

consume we can produce our own

carbohydrates using met metabolic

pathways The Source would be bread

vegetables um chocolates and honey here

are your sugars and their structure

monosaccharide just one disaccharide two

and polysaccharides many so there are

two types of monosaccharides you have

the glucose and the fructose then for

this disaccharides you have the sucrose

meaning a glucose and a fructose

combined lactose is the galactose and a

glucose combined and maltose you have

the glucose and another glucose now when

you combined a lot of sugars you'll have

the polysaccharide okay one example

would be starch okay that is very long

okay it's just a portion of starch okay

so I have here a table summarizing the

different types of polyc right so for

starch it is the energy storage for

plants one example example would be and

I think the best example would be potato

pasta and rice are also starch so starch

is a quick energy source for the body

that's why we eat rice then we also have

glycogen it is the energy storage for

animals and you have to remember that it

is formed in the liver followed by

cellulose which gives structural support

in Plants they are mostly found in the

cell ball we also have the kenee which

provides structural support and

protection they are found in the

exoskeletons of the arthropods and the

fungal cells next we'll have the lipid

next we'll have the lipids these are

your fats okay and as you can see you

have here a saturated fat and a trans

fat okay when we say saturated fat

meaning it's a fat that doesn't have any

double Bonds in their structure later

I'm going to show you so saturated fat

is actually bad okay because it

increases LDL or your bad cholesterol so

if you have high bad cholesterol you're

prone to heart attack but trans fat on

the other hand is actually worse because

it doesn't only increase your bad

cholesterol it also reduces your good

cholesterol so you can avoid fats but

it's not really 100% avoidable because

again there are good so yeah you can eat

that burger now the function of lipids

are energy storage okay so if for

example you're fasting intermittent

fasting once your body consumes all the

carbohydrates it can start using or

utilizing lipids or the fats to get

energy so in turn you're getting energy

and then you're losing fat we have

insulation so if you notice people who

are um horizontally challenged they

don't get cold easily because they have

a lot of insulation in the form of ose

tissues and then most important is that

they make up the cell membrane so the

common elements found are carbon

hydrogen and oxygen but sometimes they

have phosphorus so the building block or

the monomer are fatty acids and a

glycerol the polymer would be

triglycerides phospholipids steroids

which we will discuss soon so lipids

came from the food we consume such as

oils butter avocados and nuts this part

is very important you should know that

lipids are

hydrophobic and of course they do not

dissolve in water because again they are

water fearing that's why if you eat oily

fruit food and you just wash it with

water they don't get removed right you

have to use dishwashing liquid because

this swashing liquid is a surfactant and

there are two types of lipids again as

mentioned you have the unsaturated and

the saturated lipids so saturated lipids

as you can see in the structure this is

linear it's straight here and you don't

see a double bond in the longest chain

saturated lipids are solid at room

temperature best example would be butter

so they are predominantly found in

animal

fats

unsaturated lipids they have at least

one double or triple bonds because of

that they are liquid at room temperature

unsaturated lipids they are mostly found

in plant-based oils and oily fish next

let's have the proteins or the building

blocks the green one okay so this is why

people who go to the gym eat a lot of

proteins because it builds muscle they

build us up now the function again is

for structural support it catalyzes

biochemical reactions so these are

called enzymes enzymes are proteins by

the way they transport molecules in and

out of the system and they also function

in communication between cells so these

are your hormones and receptors finally

proteins also help in the immune

response you have the antibodies so your

hair nails muscles they are all proteins

yes including your cuticle so here are

the common elements of proteins you have

carbon hydrogen oxygen nitrogen and some

or few proteins have sulfur so the

building block of proteins are amino

acids and there are 20 Amino acids nine

of them are essential amino acids

meaning your body cannot produce this

amino acids that's why you have to get

it from the food that you consume 11 of

them are nonessential amino acids it's

not important for you to take this from

the food that you eat because your body

can produce this and then the polymer

would be a protein and a polypeptide sir

what's the difference between protein

protein and

polypeptides okay you should remember

that proteins are

polypeptides but not all polypeptides

are proteins for a polypeptide to be

considered protein it needs to have a

certain fold in the red blood cell you

have hemoglobin hemoglobin is an example

of proteins now what is the structure of

protein actually they're all the same

it's like this you can see the nitrogen

carbon oxygen and the bonds so the bond

that connects these elements are called

the peptide bonds so the only thing that

differs in each protein are the amino

acids or the R Group now there are four

structures of protein first is the

primary structure as you can see primary

structure it's just linear so you can

think of it as the friendship bracelet

then if you fold this primary structure

you'll have the secondary structure okay

so a secondary structure that looks like

a spiral shape is called the alpha Helix

however if it looks like a folded one it

will be called as a beta Helix for the

tertiary you just have to fold the

secondary structure again it is the 3D

structure of polypeptide chain and they

are held by different forces like

hydrogen bonding etc etc and finally you

have the quinary structure so this is

when two or more polypeptide chains come

together so proteins have quinary

structures lastly we're going to have

the nucleic acids this is the genetic

material it doesn't necessarily come

from the food because nuclic acids are

basically in our body but yes we can

still get nuclic acids from the food

that we eat so the function of nucleic

acids are the following first storage

and transmission of genetic information

so heredity then you have protein

synthesis for the elements it contains

carbon hydrogen oxygen nitrogen and

phosphorus the building block of nucleic

acids are the nucleotides so this

picture shows a nucleotide and a

nucleotide is composed of three things

again it must be composed of three

things things you have the sugar

phosphate and the nitrogen base so the

sugar here is the

pentos sugar why pen because you have

five carbon 1 2 3 4 five and the suffix

o meaning it's sugar then you have the

phosphate group and the nitrogen base

now the nitrogen base differs if you

have DNA the nitrogen base would be

Adine thymine guanine and cytosine but

if you have an RNA your nitrogen bases

would be adenine guanine cytosine and

uracil okay and then if you have a lot

of

nucleotides then you will form DNA which

is the genetic material RNA which is the

recipe for protein and ATP which is the

energy currency of the body