Introduction to Anatomy

• Anatomy involves studying the structure and organization of living organisms.
• This includes cells, tissues, organs, and body systems.
• Anatomy can be explored through dissection, imaging, and microscopic analysis.

Levels of Anatomical Organization

• The study of anatomy is hierarchical.
• Chemical level includes atoms and molecules.
• Cells are the basic biological units at the cellular level.
• Tissues are groups of similar cells with specific functions.
• Organs consist of different tissues working together.
• Organ systems are different organs working closely together.
• The organismal level represents the complete organism with all structural levels combined.

Anatomical Terminology

• Standardized anatomical terms are used to describe the body.
• Anatomical position is the reference: body erect, feet slightly apart, palms forward.
• Directional terms: superior/inferior, anterior/posterior, medial/lateral, proximal/distal, superficial/deep.
• Body planes: sagittal, frontal (coronal), transverse (horizontal).

Key Anatomical Structures

• Bones provide support, protection, and enable movement.
• Muscles facilitate movement, maintain posture, and generate heat.
• The heart pumps blood throughout the body.
• Lungs facilitate gas exchange.
• The brain is the control center of the nervous system.
• The stomach aids in digestion.
• Kidneys filter waste from the blood and regulate fluid balance.
• The liver produces bile, metabolizes drugs, and stores glycogen.

RNA (Ribonucleic Acid)

• RNA is in all living cells.
• RNA carries instructions from DNA to control protein synthesis.
• RNA is single-stranded, unlike DNA.

Types of RNA

• Messenger RNA (mRNA) carries genetic information from DNA to ribosomes.
• Transfer RNA (tRNA) transfers amino acids during protein synthesis.
• Ribosomal RNA (rRNA) is a structural component of ribosomes.
• Small nuclear RNA (snRNA) processes pre-mRNA in the nucleus.
• MicroRNA (miRNA) regulates gene expression.

RNA Structure

• RNA comprises nucleotides.
• Each nucleotide has a ribose sugar, a phosphate group, and a nitrogenous base.
• RNA nitrogenous bases: adenine (A), guanine (G), cytosine (C), and uracil (U).
• Uracil replaces thymine (T) in DNA.
• RNA molecules form complex 3D structures based on their sequence.

RNA Synthesis (Transcription)

• Transcription synthesizes RNA from a DNA template.
• RNA polymerase is the enzyme for transcription.
• Transcription occurs in the nucleus in eukaryotes and involves initiation, elongation, and termination.
• mRNA undergoes processing like splicing, capping, and polyadenylation.

Chemistry of Life

• Life's chemistry is based on carbon molecules.
• Organic chemistry studies carbon compounds.
• Key elements include carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur (CHONPS).
• Water is essential for its solvent properties, high heat capacity, and role in chemical reactions.

Biomolecules

• Carbohydrates provide energy and structural support, including monosaccharides, disaccharides, and polysaccharides.
• Lipids such as fats, oils, phospholipids, and steroids function in energy storage, insulation, and cell membrane structure.
• Proteins have diverse roles, including enzymes, structural components, hormones, and antibodies, and are composed of amino acids.
• Nucleic acids, including DNA and RNA, store and transmit genetic information.

Water

• Water is polar due to unequal electron sharing between oxygen and hydrogen.
• Water's properties include cohesion (molecules stick together), adhesion (molecules stick to other substances), high specific heat (resists temperature changes), and being a versatile solvent.

Carbon and Organic Molecules

• Carbon can form four covalent bonds.
• Carbon skeletons vary in length and shape, including double bonds and rings.
• Functional groups attached to carbon skeletons determine chemical properties.

Carbohydrates

• Simple sugars like glucose and fructose are monosaccharides.
• Disaccharides form by joining two monosaccharides (e.g., sucrose and lactose).
• Complex carbohydrates like starch, glycogen, and cellulose are polysaccharides.

Lipids

• Fats and oils are triglycerides of glycerol and fatty acids.
• Saturated fatty acids have no double bonds, while unsaturated fatty acids have one or more.
• Phospholipids are major components of cell membranes.
• Steroids include cholesterol and hormones like testosterone and estrogen.

Proteins

• Proteins are amino acid polymers linked by peptide bonds.
• Primary protein structure: amino acid sequence.
• Secondary protein structure: local folding patterns (alpha helices and beta sheets).
• Tertiary protein structure: three-dimensional structure.
• Quaternary protein structure: arrangement of multiple polypeptide chains.
• Enzymes catalyze biochemical reactions.

Nucleic Acids

• DNA stores genetic information.
• RNA is involved in protein synthesis.
• Nucleic acids are nucleotide polymers.
• Nucleotides consist of a sugar (deoxyribose or ribose), a phosphate group, and a nitrogenous base.
• DNA nitrogenous bases: adenine (A), guanine (G), cytosine (C), thymine (T).
• RNA nitrogenous bases: adenine (A), guanine (G), cytosine (C), uracil (U).

Overview of anatomy, the study of the structure and organization of living things. Includes levels of organization from chemical to organismal. Covers anatomical terminology, planes, and directional terms for standardized body description.