just 1 lesson of my biology notes
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you don’t actually have to thoroughly read it, it’s just to get the gist of how much of it there is
Proteins are the most abundant and functionally versatile of the cellular macromolecules.
Remember macromolecules are large molecules that make up the chemical components of
the cell.Structure
● Consist of long chains of subunits called amino acids.
Amino acids are made up of a carboxyl group
(COOH), side chain, hydrogen and an amino group
(NH2).
● Amino acids are held together by peptide bonds. This
makes a polypeptide chain.
● Proteins are formed by twisting up one or more
polypeptide chains. It is the shape, or conformation, of
the protein that gives it its properties.
● Found in 4 levelsFunction
Proteins are used for structure –
EX: hair and nails, muscle fibers
Proteins act as messengers.
EX: hormones - chemical messengers that aid
communication between your cells, tissues and organs.
Proteins support immune health
EX: antibodies - help protect the body from harmful
invaders
Proteins are used for transport –
EX: hemoglobin transports oxygen in the blood
Proteins are involved in chemical reactions
EX: enzymes - speed up reactionsAn amino acid contains both a
carboxyl group and an amino
group.Each molecule contains a central
carbon © atom, called the α-carbon,
to which both an amino (NH2) and a carboxyl group (COOH) are
attached. The remaining two bonds of
the α-carbon atom are generally
satisfied by a hydrogen (H) atom and
the R group.Proteins have 4 structural levels: Primary, Secondary, Tertiary and Quaternary
Primary: Sequence of amino acids, determined by gene DNA held together by peptide bonds between the amino acids, to make a polypeptide chainSecondary: Repeated patterns of folding of the protein backbone. The two most common folding patterns are the alpha helix and the beta sheet, held together byhydrogen bonds.
Tertiary: Folding of the entire protein into a characteristic shape. Folding is based on the interactions of the side chain (R groups) may be globular (enzymes) or fibrous (hair and proteins) may be held together by covalent, ionic, and hydrogen bonds
Quaternary:
Association of 2 or more polypeptide (protein) chainsHow do proteins work in the body?
Our bodies are made up of thousands of different proteins, each with a specific function. They make up the structural components of our cells and tissues as well as many enzymes, chemical
reactions - Digestion, energy production, muscle contraction, hormones and the makeup of our immune cells. What we think of as “protein” is actually a large category of molecules. These body proteins are continually being repaired and replaced throughout our lives. This process (known as ‘protein synthesis’) requires a continuous supply of amino acids. Although some amino acids can be recycled from the breakdown of old body proteins, this process is imperfect. This means we must eat dietary protein to keep up with our body’s amino acid demand.
As protein is essential for cell and tissue growth, adequate intake of protein is particularly important during periods of rapid growth or increased demand, such as childhood, adolescence, for example.
Amino acids are classified as either essential or non-essential. Essential amino acids cannot be produced by the body and therefore must come from our diet. Whereas, non-essential amino acids can be produced by the body and therefore do not need to come from the diet. The nutritional value of a protein is measured by the quantity of essential amino acids it contains.
● Animal products (such as chicken, beef or fish and dairy products) have all of the essential amino acids and are known as ‘complete’ protein (or ideal or high-quality protein).
● Plant proteins (beans, lentils, nuts and whole grains) usually lack at least one of the essential amino acids and are considered
‘incomplete’ proteins.There are two main types: DNA and RNA
DNA provides the code for the cell’s activities, while RNA converts that code into proteins to carry out cellular functions.Structure
Made up of repeating monomers called nucleotides.
Nucleotide - made up of three parts: a monosaccharide sugar (deoxyribose or ribose), a nitrogen base (A,T,C,G or U) , and a phosphate group.
Example of single nucleotide – Adenosine triphosphate (ATP). ATP is the energy molecule of the cell.Function
Store and transmit inherited information in the forms of DNA and
RNA.
DNA controls all of the cellular activities by turning the genes “on” or “off. ”. Many genes contain the information to make protein products; other genes code for RNA products.
Cells access the information stored in DNA by creating RNA to
direct the synthesis of proteins through the process of translation.
In eukaryotes, such as plants and animals, DNA is found in the nucleus. as well as in certain other types of organelles (such as mitochondria and the chloroplasts of plants).In prokaryotes, such as bacteria, the DNA it’s located in a specialized region - nucleoid.
In eukaryotes, DNA is typically broken up into a number of very long, linear pieces called chromosomes. A chromosome may contain tens of thousands of genes, each providing instructions on how to make a particular product needed by the cell. While we need nucleic acids in your body, we don’t need them in our diet. As humans, we have a very limited ability to take up the building blocks of nucleic acids, called nucleotides, from the digestive tract. Instead, we tend to make our own nucleotides, using amino acids as precursors.
As such, when you consume protein and digest it into amino acids, you’re obtaining the building blocks for both proteins and, eventually, nucleic acids.What is the relationship between nucleotide sequence and amino acid sequence? Amino acid sequence originates from an mRNA sequence. The mRNA sequence originates as a result of the transcription of a gene in which the order of the nucleotides in the coding sequence decides the resulting protein. Three nucleotides collectively make a codon, which in turn decides the amino acid. (This process will be introduced in future classes)
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I actually kinda understand this not really but a bit- -
jun bro it gave me a stomach ache ;-;
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jun aint no way yo biology notes gave me a damn stomach ache
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jun Thanks
