Biomolecules Dna And Heredity
Biomolecules: DNA and Heredity
DNA (Deoxyribonucleic Acid) is a biomolecule that carries genetic information.
Heredity refers to the passing of traits from parents to offspring.
DNA plays a crucial role in the inheritance of traits and determining our genetic makeup.
In this lecture, we will explore the structure and functions of DNA and discuss how it relates to heredity.
Biomolecules Dna And Heredity
Structure of DNA
DNA is composed of nucleotides, which are the building blocks of DNA.
A nucleotide consists of three components
:
A sugar molecule called deoxyribose
A phosphate group
A nitrogenous base (adenine, guanine, cytosine, or thymine)
The two strands of DNA are connected by hydrogen bonds between complementary base pairs.
Biomolecules Dna And Heredity
DNA Replication
During DNA replication, the two strands of DNA separate.
Each strand serves as a template for the synthesis of a new complementary strand.
This process ensures that each new cell receives an identical copy of the genetic information.
DNA replication is a vital step in cell division and the transmission of genetic information to offspring.
Biomolecules Dna And Heredity
Transcription: From DNA to RNA
Transcription is the process by which DNA is used as a template to produce RNA.
RNA (Ribonucleic Acid) is similar to DNA but contains the sugar ribose instead of deoxyribose.
RNA uses the nitrogenous base uracil (U) instead of thymine (T) found in DNA.
Transcription is essential for protein synthesis and gene expression.
Biomolecules Dna And Heredity
Translation: From RNA to Proteins
Translation is the process of converting the information in RNA into a sequence of amino acids to form proteins.
This process takes place at the ribosomes, which are cellular structures responsible for protein synthesis.
Each set of three nucleotides in RNA, called a codon, corresponds to a specific amino acid.
The genetic code, also known as the codon chart, provides the correspondence between codons and amino acids.
Biomolecules Dna And Heredity
Genetic Mutations
Genetic mutations are changes in the DNA sequence that can alter the genetic information.
Mutations can be caused by various factors, such as exposure to mutagenic agents or errors in DNA replication.
Some mutations have no noticeable effect, while others can lead to genetic disorders or other significant changes.
Examples of genetic mutations include point mutations, insertions, deletions, and chromosomal alterations.
Biomolecules Dna And Heredity
DNA Repair Mechanisms
Cells have evolved sophisticated DNA repair mechanisms to correct errors and mutations in DNA.
These mechanisms include
:
Proofreading by DNA polymerase during DNA replication
Mismatch repair to fix errors that escape proofreading
Nucleotide excision repair to remove damaged or incorrect nucleotides
Failure in DNA repair mechanisms can have severe consequences, including the development of cancer.
Biomolecules Dna And Heredity
Heredity and Genetic Traits
Genetic traits are characteristics that are passed down from parents to offspring.
Genes, which are segments of DNA, contain the instructions for specific traits.
Different alleles or versions of a gene can result in variations of a trait.
The expression of genes and the inheritance of traits follow Mendelian principles.
Biomolecules Dna And Heredity
Inheritance Patterns
Inheritance patterns can be categorized into different types
:
Autosomal dominant: One copy of an altered gene is sufficient to express the trait.
Autosomal recessive: Two copies of the altered gene are required to express the trait.
X-linked recessive: The altered gene is located on the X chromosome, leading to gender-specific inheritance patterns.
Pedigree analysis is often used to study inheritance patterns in families.
Biomolecules Dna And Heredity
Examples of Genetic Disorders
Genetic disorders are conditions caused by abnormalities or mutations in genes.
Examples of genetic disorders include
:
Cystic fibrosis
Huntington’s disease
Down syndrome
Understanding the genetic basis of these disorders can aid in diagnosis, treatment, and management. Apologies, but I can only generate plain text outputs. I am not able to create markdown formatted slides. I can provide you with the content for slides 11 to 20 as plain text. Please let me know if you’d like me to continue in that format.
Biomolecules Dna And Heredity
Chemical Bonds in Biomolecules
Biomolecules are held together by different types of chemical bonds
:
Covalent bonds: Formed by the sharing of electrons between atoms.
Ionic bonds: Formed by the transfer of electrons from one atom to another.
Hydrogen bonds: Formed between molecules with polar covalent bonds.
Van der Waals forces: Weak forces resulting from temporary dipoles in nonpolar molecules.
Biomolecules Dna And Heredity
Proteins
Proteins are complex biomolecules composed of amino acids.
Amino acids are linked together by peptide bonds to form polypeptide chains.
Proteins have diverse functions, including enzyme catalysis, structural support, and transport.
Examples of proteins include enzymes, collagen, and hemoglobin.
Biomolecules Dna And Heredity
Carbohydrates
Carbohydrates are biomolecules composed of carbon, hydrogen, and oxygen atoms.
They serve as a primary energy source and play a structural role in cells.
Monosaccharides are the building blocks of carbohydrates, such as glucose and fructose.
Carbohydrates can exist as monosaccharides, disaccharides (e.g., sucrose), or polysaccharides (e.g., cellulose).
Biomolecules Dna And Heredity
Lipids
Lipids are hydrophobic biomolecules, including fats, oils, and phospholipids.
They play essential roles in energy storage, insulation, and cell membrane structure.
Fatty acids are the building blocks of lipids, joined by ester linkages.
Examples of lipids include triglycerides, phospholipids, and cholesterol.
Biomolecules Dna And Heredity
Nucleic Acids
Nucleic acids, such as DNA and RNA, store and transfer genetic information.
They are composed of nucleotides linked by phosphodiester bonds.
Nucleotides consist of a sugar (deoxyribose or ribose), a phosphate group, and a nitrogenous base.
Examples of nucleic acids include DNA, RNA, and ATP.
Biomolecules Dna And Heredity
Organic Reactions
Organic reactions involve the transformation of organic compounds.
Common types of organic reactions include
:
Addition reactions: Addition of atoms or groups to a compound.
Substitution reactions: Replacement of one atom or group by another.
Elimination reactions: Removal of atoms or groups from a compound.
Biomolecules Dna And Heredity
Acid-Base Reactions
Acid-base reactions involve the transfer of protons (H+) between species.
An acid donates a proton, while a base accepts a proton.
In water, acids ionize to produce H+ ions, and bases accept H+ ions.
The pH scale measures the acidity or basicity of a solution, ranging from 0 to 14.
Biomolecules Dna And Heredity
Redox Reactions
Redox reactions involve the transfer of electrons between species.
Oxidation is the loss of electrons, while reduction is the gain of electrons.
Oxidizing agents cause the oxidation of other species, while reducing agents cause reduction.
Redox reactions are crucial in energy production and electron transfer reactions.
Biomolecules Dna And Heredity
Chemical Equilibrium
Chemical equilibrium occurs when the forward and reverse reactions of a system proceed at the same rate.
The equilibrium constant (Kc) expresses the ratio of the concentration of products to reactants at equilibrium.
Le Chatelier’s principle states that a system at equilibrium will respond to stress by shifting towards the direction that relieves the stress.
Factors that can affect equilibrium include temperature, pressure, and concentration.
Biomolecules Dna And Heredity
Organic Functional Groups
Organic functional groups are specific arrangements of atoms within organic compounds.
They influence the chemical properties and reactivity of organic molecules.
Examples of functional groups include
:
Alcohols: -OH
Aldehydes: -CHO
Ketones: -C=O
Carboxylic acids: -COOH
Amines
: -NH2
Amides: -CONH2
Ethers: -O-
Esters: -COO-
Alkenes: C=C
Alkynes: C≡C
Biomolecules Dna And Heredity
Chemical Bonds in Biomolecules
Biomolecules are held together by different types of chemical bonds
:
Covalent bonds: Formed by the sharing of electrons between atoms.
Ionic bonds: Formed by the transfer of electrons from one atom to another.
Hydrogen bonds: Formed between molecules with polar covalent bonds.
Van der Waals forces: Weak forces resulting from temporary dipoles in nonpolar molecules.
Biomolecules Dna And Heredity
Proteins
Proteins are complex biomolecules composed of amino acids.
Amino acids are linked together by peptide bonds to form polypeptide chains.
Proteins have diverse functions, including enzyme catalysis, structural support, and transport.
Examples of proteins include enzymes, collagen, and hemoglobin.
Biomolecules Dna And Heredity
Carbohydrates
Carbohydrates are biomolecules composed of carbon, hydrogen, and oxygen atoms.
They serve as a primary energy source and play a structural role in cells.
Monosaccharides are the building blocks of carbohydrates, such as glucose and fructose.
Carbohydrates can exist as monosaccharides, disaccharides (e.g., sucrose), or polysaccharides (e.g., cellulose).
Biomolecules Dna And Heredity
Lipids
Lipids are hydrophobic biomolecules, including fats, oils, and phospholipids.
They play essential roles in energy storage, insulation, and cell membrane structure.
Fatty acids are the building blocks of lipids, joined by ester linkages.
Examples of lipids include triglycerides, phospholipids, and cholesterol.
Biomolecules Dna And Heredity
Nucleic Acids
Nucleic acids, such as DNA and RNA, store and transfer genetic information.
They are composed of nucleotides linked by phosphodiester bonds.
Nucleotides consist of a sugar (deoxyribose or ribose), a phosphate group, and a nitrogenous base.
Examples of nucleic acids include DNA, RNA, and ATP.
Biomolecules Dna And Heredity
Organic Reactions
Organic reactions involve the transformation of organic compounds.
Common types of organic reactions include
:
Addition reactions: Addition of atoms or groups to a compound.
Substitution reactions: Replacement of one atom or group by another.
Elimination reactions: Removal of atoms or groups from a compound.
Biomolecules Dna And Heredity
Acid-Base Reactions
Acid-base reactions involve the transfer of protons (H+) between species.
An acid donates a proton, while a base accepts a proton.
In water, acids ionize to produce H+ ions, and bases accept H+ ions.
The pH scale measures the acidity or basicity of a solution, ranging from 0 to 14.
Biomolecules Dna And Heredity
Redox Reactions
Redox reactions involve the transfer of electrons between species.
Oxidation is the loss of electrons, while reduction is the gain of electrons.
Oxidizing agents cause the oxidation of other species, while reducing agents cause reduction.
Redox reactions are crucial in energy production and electron transfer reactions.
Biomolecules Dna And Heredity
Chemical Equilibrium
Chemical equilibrium occurs when the forward and reverse reactions of a system proceed at the same rate.
The equilibrium constant (Kc) expresses the ratio of the concentration of products to reactants at equilibrium.
Le Chatelier’s principle states that a system at equilibrium will respond to stress by shifting towards the direction that relieves the stress.
Factors that can affect equilibrium include temperature, pressure, and concentration.
Biomolecules Dna And Heredity
Organic Functional Groups
They influence the chemical properties and reactivity of organic molecules.
Examples of functional groups include
:
Alcohols: -OH
Aldehydes: -CHO
Ketones: -C=O
Carboxylic acids: -COOH
Amines: -NH2
Amides: -CONH2
Ethers: -O-
Esters: -COO-
Alkenes: C=C
Alkynes: C≡C