C,H,O,N,P,S,K,Ca,Mg

Fe,Mn,Zn,Cu,B,Mo

Protein (7%~10%)

Lipids (1%~2%)

Sugars and nucleic acids (1%~1.5%)

Water (70%~90%)

Inorganic salt (1%~1.5%)

Liquid A: 01g/ml NaOH solution

Liquid B: 0.05g/ml CuSO₄ solution

Water bath heating 50℃~65℃ 2min

Mix equal parts ready for use

Formation of brick red precipitate

Wash away the floating color with 50% alcohol solution by volume

Observe orange fat particles under low magnification

Solution A: 0.1g/ml NaOH solution

Liquid B: 0.01g/ml CuSO₄ solution

Ready for use, add drops in sequence

A purple reaction occurs

Easy to flow and easy to evaporate

Loss of free water when dried

effect

Not easy to flow and not easy to lose

Loss of bound water during drying

Role: an important component of cell structure

Cooling: free water → bound water (warming and vice versa)

Free water → bound water (life activities slow down, metabolism slows down)

Bound water → free water (strong life activities and accelerated metabolism)

Free water/bound water↑strong cell metabolism and weak stress resistance

Free water/bound water↓Slow ​​cell metabolism and strong stress resistance

When the oxygen end of one water molecule is close to the hydrogen end of another water molecule, the electrostatic attraction between them forms a weak attraction - a hydrogen bond.

The temperature of water is relatively difficult to change

Hydrogen bonds are weak, easily broken, and can only last for a very short time. Hydrogen bonds are constantly broken and formed.

Important component of complex intracellular compounds

Maintain normal life activities of cells and organisms

Maintain cell acid-base balance

Maintain osmotic pressure balance inside and outside cells

Carbohydrates abbreviated as CH₂O

Five-carbon sugar (cannot be oxidized to provide energy)

six carbon sugar

Maltose (reducing sugar)

Sucrose (non-reducing sugar)

Lactose (reducing sugar)

starch

glycogen

cellulose

Chitin (chitin)

Compared with sugars, the H content is higher and the O content is much lower than sugars.

One molecule of glycerol, three molecules of fatty acid → triacylglycerol (triglyceride)

effect

Fat is generally only broken down to provide energy when carbohydrates are insufficient and cannot be converted into carbohydrates in large quantities.

One hydroxyl group of glycerol is combined with phosphoric acid and its derivatives (C H O N P)

Mainly distributed in the brains, egg cells, livers and soybean seeds of humans and animals

It is an important component of cell membranes and various organelle membranes.

cholesterol

sex hormones

Vitamin D

The difference between amino acids is the difference in the R group

Side chain groups determine the type and physical and chemical properties of amino acids

Essential Amino Acids (8)

Non-essential amino acids (13)

Dehydration condensation: The carboxyl group of one amino acid molecule is connected to the amino group of another amino acid molecule, and a molecule of water is removed at the same time.

The chemical bond that connects two amino acid molecules is called a peptide bond

Compounds formed by the condensation of multiple amino acids and containing multiple peptide bonds are called polypeptides

Different types of amino acids

Different amounts of amino acids

Amino acids are arranged in different order

The way polypeptide chains twist and fold and the spatial structures they form vary widely.

Physical changes are recoverable

Does not affect protein properties

peptide bond cleavage

Proteins can be broken down into short peptides or amino acids

Mainly distributed in the nuclei of eukaryotic cells & nucleoids of prokaryotic cells

Mitochondria and chloroplasts also contain small amounts of

Mainly distributed in the cytoplasm

Small amount in cell nucleus

Nucleotide: one molecule of five-carbon sugar, one molecule of phosphate, one molecule of nitrogenous base

DNA: Deoxyribonucleotide

RNA: Ribonucleotide

Made up of two deoxyribonucleotide chains

characteristic

Carbon is the core element of life. Without carbon, there would be no life.

Made up of a chain of ribonucleotides

is the substance that carries genetic information within cells

It plays an extremely important role in the genetic variation of organisms and protein biosynthesis.

polysaccharide

protein

nucleic acid

The basic unit of biological macromolecules

Each monomer has a carbon chain composed of several adjacent carbon atoms as a backbone.

Biological macromolecules are polymers composed of many monomers linked together