Biology Notes - Introduction to Anatomy

UNIT 1: INTRODUCTION TO ANATOMY A\) What is Anatomy? study of internal and external body structures relationships between structures e.g. bone and muscle Subdivisions: 1\) Microanatomy microscope required cytology is \_\_\_study of cells\_ histology is the study of tissues (grou...

UNIT 1: INTRODUCTION TO ANATOMY A\) What is Anatomy? study of internal and external body structures relationships between structures e.g. bone and muscle Subdivisions: 1\) Microanatomy microscope required cytology is \_\_\_study of cells\_ histology is the study of tissues (groups of cells) 2\) Gross Anatomy visible to the eye e.g. bone, heart, stomach, etc. body cavities (e.g. cranial, thoracic, abdominopelvic) B\) Levels of Organization (simple to complex) 1\) Chemical level (basic level) atoms e.g. Hydrogen (H) and Oxygen (O) atoms atoms join to form molecules e.g. H~2~O (water) 2\) Cellular level molecules form organelles which form cells cells are the basic unit of structure and function of the body all cells contain chemicals, but the function of different types of cells may differ e.g. erythrocytes (red blood cells), neurons, muscle cells 3\) Tissue level a group of structurally similar cells with a common function 4 major types: epithelial connective muscle nervous 4\) Organ level Two or more \_\_\_\_\_\_\_tissues\_\_\_\_\_ working together for a common function e.g. stomach is made up of all four major tissues function is digestion 5\) Organ system level several related organs that work together to accomplish a common purpose e.g. respiratory system lungs, larynx, trachea, and other organs. function is respiration 6\) Organism All systems function together to maintain life Note: This is a [Hierarchy] - each level contains those below. UNIT 2: Chemical Level of Organization Knowledge of basic chemistry is needed for understanding anatomy and physiology and the difference between healthy and diseased person. A\) Structure of an atom All matter, including all parts of the human body, is made from particles called atoms Atoms have three types of subatomic particles: The nucleus of an atom contains: \_\_\_\_\_\_\_\_\_\_protons\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_neutrons\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ Orbiting (floating around) the nucleus there are: electrons (e^-^): negative charge B\) [Ions] if an atom loses or gains an electron, it is [no longer neutral] and becomes an ion atom gains electrons it becomes a \_\_\_\_\_\_\_negative\_\_\_\_\_\_\_\_\_\_\_\_\_ ion (**anion**) atom loses electrons it becomes a \_\_\_\_\_\_\_\_\_positive\_\_\_\_\_\_\_\_\_\_\_ ion (**cation**) Important ions (also known as electrolytes): Calcium: Ca^2+^ Sodium: Na^+^ Potassium: K^+^ Hydrogen: H^+^ Chloride: Cl^-^ C\) Chemical Bonds Bond (hold) atoms together to form molecules [Types of bonds:] \_\_\_ionic\_\_\_\_\_\_\_\_ bond (ions formed) - atom to atom transfer of electrons e.g. NaCl (table salt): not all salts are table salt! Salts consist of positively charged ions (cations) and negatively charged ions (anions) (e.g. NaCl, KCl) Na loses one electron and becomes Na^+^ Cl gains one electron and becomes Cl^-^ the positive (Na^+^) and negative (Cl^-^) ions attract forming the bond in H~2~O NaCl dissociates (dissolves/separates/ionizes) into ions: Na^+^, Cl^-^ \_\_\_\_\_\_covalent\_\_\_\_\_\_\_bond - sharing electrons between atoms e.g. O~2~ These chemical bonds allow the formation of chemical compounds which may be organic or inorganic: Organic substances - covalently bonded carbon (C) atoms e.g. carbohydrates, proteins, lipids and nucleic acids inorganic substances -- usually lack C atoms water (H~2~O) salts - consist of positively charged ions (cations) and negatively charged ions (anions) (e.g. NaCl) gases (O~2~) with the exception of these inorganic compounds which contain carbon atoms: H~2~CO~3~ (Carbonic Acid) HCO~3~^-^ (Bicarbonate) CO~2~ (Carbon Dioxide) CO (Carbon Monoxide) D\) Water (inorganic) Most abundant substance in cells 2 hydrogen (H) atoms and 1 Oxygen (O) \_\_\_\_\_polar\_\_\_\_\_\_\_ molecules -- unequal sharing of electrons leads to a slight charge difference Many reactions in the body take place in H~2~O because it is a universal solvent Transports chemicals e.g. O2, nutrients Maintains body temperature (\~37°C) E\) Acids and Bases can be organic [OR] inorganic Like salts, acids and bases are electrolytes, though they also play a critical role in maintaining the pH balance of cells, organs, and blood within narrow ranges. Acids: dissociate in H~2~O releasing H^+^ ions ↑\[H^+^\] =↓pH (high hydrogen ion concentrations indicate a low or acidic pH) e.g. hydrochloric acid (HCl) in H~2~O H^+^ + Cl^-^ Bases: substances that bind to (or *buffer*) free H^+^ ions (in H~2~O) ↓ \[H^+^\] =↑pH (low hydrogen ion concentrations indicate a high pH) e.g. 1: NaOH (base) in H~2~O Na^+^ + OH^-^ (hydroxyl ion) e.g. 2: [HCO~3~^-^] (bicarbonate) + H^+^ H~2~CO~3~ (carbonic acid) H2O + CO2 OH^-^ and HCO~3~^-^ act as bases by binding to the free H^+^ ions pH Scale: a measure of the \[H^+^\] of free H^+^ in solution Basic Acidic ↑\[H^+^\] e.g. pH of blood = 7.35 - 7.45 0 \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-- 7 \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-- 14 acidic Neutral basic/alkaline [OH^-^ ] + H^+^ H~2~O (neutralization) F\) Important Organic Substances Carbohydrates consist of C,H, and O formula: (CH~2~0)~n~ \[n = \#\] Functions: Source of energy for cells e.g. C~6~H~12~O~6~ (glucose) Cellular structures e.g. DNA + RNA Naming: monosaccharides (simple sugars) e.g. glucose, fructose, ribose, deoxyribose basic building blocks of other carbohydrates disaccharides - 2 monosaccharides covalently bonded together e.g. glucose + fructose sucrose polysaccharides - many monosaccharides (basic building blocks) bonded together e.g. glycogen (animals), starch (plants) Lipids C, H, O (ratio different from carbs) e.g. fats, oils, waxes, fatty acids (FA) Insoluble (nonpolar) in water Functions: protect organs (padding) build cell membranes source of stored energy Types: Glycerides most common lipid in body and diet composed of 2 building blocks: glycerol (backbone) fatty acids (FAs) naming: glycerol + 1 FA = monoglyceride glycerol + 2 FAs = diglyceride glycerol + 3 FAs = triglyceride Phospholipids 3 building blocks: Phosphate "Head" Group (polar) hydrophillic (water soluble) Glycerol backbone and iii. 2 FAs "tails" (non-polar) hydrophobic (water insoluble) ie: diglyceride with a phosphate head group Cholesterol found in cell membranes and used to synthesize steroids Steroids derived from cholesterol e.g. bile salts, vitamin D, some hormones (e.g. testosterone, estrogen) Proteins consists of C, H, O, N, (also sometimes S) e.g. collagen Functions: structural materials e.g. collagen enzymes, hormones, transporters antibodies source of energy (especially when carbs & lipids in low supply) [Naming:] Amino acids basic building blocks of all proteins use the name of the aa itself e.g. glycine dipeptides two amino acids polypeptides many amino acids protein one or more polypeptides folded into its final shape Nucleic Acids consists of C, H, O, N, P 2 forms: DNA (deoxyribonucleic acid) RNA (ribonucleic acid) building blocks called nucleotides each nucleotide contains: PO~4~^-^ (phosphate) monosaccharide (simple sugar) ribose in RNA or deoxyribose in DNA organic bases: Adenine (A) Thymine (T) -- DNA only Uracil (U) -- RNA only Cytosine (C) Guanine (G) structure: DNA PO~4~ - deoxyribose - A, T, C, or G Bases bind to form double-stranded helix (twisted ladder) A to T G to C alternating sugar and phosphate form "uprights" bases "rungs" Functions: cellular reproduction used as a template to make RNA RNA PO~4~ - ribose - A, U, C, or G single stranded A to U G to C Function: protein synthesis Adenosine Triphosphate (ATP) -- modified RNA nucleotide Energy stored in covalent bonds - powers cellular activities Structure: adenosine (ribose and adenine ) + PO~4~ (phosphate group) in fig. 2.26 "\~" = high energy bond (Adenosine - P\~P\~P) breaking bond creates immediately useable energy ATP ADP (adenosine diphosphate) + P~i~ (inorganic phosphate) UNIT 3: Cellular Level of Organization A\) The Cell Basic structural and functional unit of the body can perform all basic life functions B\) Principal Parts of the Cell: Cell Membrane/Plasma Membrane/Plasmalemma Cytoplasm Nucleus C\) Cell Membrane / Plasma Membrane / Plasmalemma Boundary between the inside and outside of a cell. Composed of: 1\) Phospholipid bilayer phosphate head group (hydrophilic) FA tails (hydrophobic) divides ICF and ECF Intracellular Fluid (ICF) = inside cell Extracellular Fluid (ECF) = outside cell 2\) Cholesterol scattered throughout membrane adds stability to the cell membrane 3\) Membrane proteins 2 types: a\) integral proteins integrated within the membrane, therefore have a hydrophobic region some extend across entire membrane, and are called transmembrane proteins b\) peripheral proteins attached to either surface of integral proteins i.e. on the periphery of the cell membrane Functions of Membrane Proteins: enzymes transporters channels receptors anchors identity markers (for immune system) 4\) Membrane carbohydrates only on **[outer]** surface bound to proteins (glycoproteins) or lipids (glycolipids) Functions: a\) cell recognition e.g. sperm recognize egg cell b\) anchor cells together 5\) Microvilli small projections of cell membrane function is to increase surface area best seen on cells of the small intestine and kidney ** 1) and 3) = Fluid Mosaic Model** of the cell membrane: fluid - membrane constituents can move around (phospholipids and some proteins) mosaic -- proteins dot surface like tiles in a mosaic D\) Cytoplasm AREA between the inside of the cell membrane and the outside of the nucleus. 2 divisions: 1\) Cytosol = gel-like intracellular fluid contains water, ions (e.g. K^+^, Na^+^) and a suspension of carbohydrates, proteins, and lipids may contain inclusions e.g. melanin (pigment), glycogen (stored glucose) 2\) Organelles structures that perform a specific function and are essential for life are either: a)non-membranous -- in direct contact with cytosol b)membranous -- surrounded by membrane that isolates them from cytosol Non-membranous organelles 1\) Ribosomes sites for protein synthesis contain ribosomal RNA (rRNA) and proteins may be: Free ribosomes -- float in cytosol and make proteins that go to cytosol, mitochondria, and/or nucleus attached to endoplasmic reticulum (ER) - make proteins destined for all other sites 2\) Centrosomes Consist of 2 components: a pair of centrioles and the pericentriolar matrix Organizing centres for microtubules spindle apparatus (for cell division) organizes cytoskeleton 3\) Cytoskeleton [ALL] types are for structural support (for cell shape) and are formed from [proteins] important in cell movement, cell division, movement/anchoring of organelles and proteins (e.g. receptors, enzymes) 3 types: a)microfilaments made of actin Functions: muscle contraction (with myosin) cell locomotion cytokinesis b)intermediate filaments composition is tissue specific e.g. keratin c)microtubules hollow tubes made of tubulin Function: form: centrioles spindle apparatus cilia (short) flagella (long) move or secure organelles in place Membranous organelles 1)Mitochondria site of ATP synthesis contains own DNA, RNA, and proteins have a double membrane 2)Endoplasmic reticulum (ER) membranous network throughout cytoplasm 2 types: Rough ER (RER) ribosomes attached - synthesis of secretory, lysosomal and membrane proteins Smooth ER (SER) lacks attached ribosomes continuous with RER synthesizes lipids and steroid hormones 3)Golgi Apparatus/Complex stacks of membrane discs modifies proteins (e.g. trims or adds carbs and lipids), sorts, packages, and delivers them to cell membrane, lysosomes, or for secretion (cellular post office) 4)Lysosomes filled with digestive enzymes digest bacteria, viruses, worn-out organelles (clean up function) E\) Nucleus largest membranous organelle cell control centre cells may have 1 or more nuclei Parts: 1)nuclear envelope double membrane with nuclear pores connected to ER 2\) nucleolus (\>1 in some plants) non-membranous dense (less light gets through) region of DNA, RNA, and proteins where ribosomes are made and assembled 3)chromosomes/chromatids contain DNA and histone proteins can be: dispersed = Chromatin DNA uncoiled and not individually visible in this form MOST of the time (when cell is not dividing condensed and individually visible found in dividing cells (during mitosis/meiosis) UNIT 4: THE CELL CYCLE, MITOSIS, MEIOSIS A\) 2 Cell Types Based on Chromosome Content: 1)Gametes: 23 different chromosomes = haploid (n) includes ova (eggs) and sperm 2\) Somatic Cells includes all cells of body except cells undergoing/resulting from meiosis e.g. muscle cell, nerve cell, etc. 46 chromosomes = diploid (2n) = 23 homologous pairs ** Homologous Chromosomes** = a chromosome pair (1 from each parent) that are highly similar in length, centromere position, and have **genes** for the same trait (e.g. eye colour) in the same location (**locus**) Gene = a unit of heredity = a region of DNA which contains information for synthesis of a protein ** BUT** the homologous chromosomes may have different [versions] of that gene (**alleles**) that code for proteins that produce alternate versions of that trait. e.g. blue eyes (chromosome from one parent), brown eyes (chromosome from the second parent) each somatic cell contains 23 different chromosome [pairs] 23 chromosomes from an ovum [paired] with 23 chromosomes from a sperm = 46 chromosomes (diploid/2n somatic cell) chromosomes and chromosome pairs are numbered 1-23: 1 to 22 = autosomal chromosomes (autosomes) contain genes for somatic characteristics e.g. hair and eye colour, height each autosomal chromosome pair is not identical, but equivalent= **homologous chromosomes** 23 = sex chromosome contain **genes** that determine biological sex, XX=Female XY=Male X or Y from sperm X from ovum B\) Cell Cycle -- for growth and repair of tissues Diploid somatic cell (2n) 2 genetically identical somatic diploid cells (2n) [2 stages:] 1)Interphase 2)Mitotic (M)/Cell Division phase 1)[Interphase (G~1~, S, G~2~ phases) ] chromosomes are present as long thread-like chromatin strands normal cellular metabolic activities occurring e.g. protein synthesis phases of interphase: a)[G~1~ Phase] growth, metabolism centrosome replication begins Note: cells that do not divide again once mature, (i.e. remain in G~1~) are said to be in the G~0~ phase e.g. nerve and some muscle cells b)[S Phase] chromosomes replicate, but are still present as long thread-like chromatin strands (not individually visible) ALWAYS occurs before cell division (mitosis and meiosis) replicates are called sister chromatids attached to each other at an area of DNA called the centromere kinetochores (proteins) form on each centromere (1/chromatid) ** kinetochore** = site of attachment of spindle microtubules c)[G~2~ Phase] growth, metabolism production of enzymes & other proteins needed for cell division centrosome replication is completed 2\) [Mitotic Phase] involves: a)mitosis = division of nuclear material (chromosomes) 4 phases, [but] continuous cycle! Prophase Metaphase Anaphase Telophase b)cytokinesis = division of the cytoplasm when mitotic phase ends: mitosis & cytokinesis complete resulting diploid cells go into interphase (G1) cycle starts over C\) Somatic Cell Formation: Mitosis 1)[Prophase] chromosomes condense (thicken, coil) - become individually visible nucleoli disappear and nuclear envelope breaks up centrosomes move to opposites sides (poles) of the cell spindle microtubules grow out of centrosomes and [attach to] kinetochore proteins of each sister chromatid, forming the spindle apparatus Spindle begins to move chromosomes toward cell equator 2)[Metaphase] ** ** replicated chromosomes line up on cell equator 3)[Anaphase] spindle microtubules shorten and pull the kinetochores away from each other -- causes separation of centromeres, which results in separation of the sister **chromatids into 92 individual chromosomes** ** 46** chromosomes migrate to [each] pole cytokinesis (division of cytoplasm) begins 4)[Telophase] chromosomes uncoil to long thread-like strands of chromatin nucleoli, nuclear envelope reappear spindle disassembles cytokinesis completes (or may end after telophase ends) D\) Gamete Formation: Meiosis = reproductive nuclear division meiosis produces [gametes] (ovum and sperm) 1 cell (diploid, 2n) produces 4 genetically unique gametes (each haploid, n) [involves:] interphase (G~1~, S, G~2~) followed by 2 cell divisions: 1) Meiosis I, immediately followed by 2) Meiosis II (no DNA replication occurs between I and II) 1)[Meiosis I] (reduction division in which chromosome number changes from 2n to n) events same as in mitosis except: a)[Prophase I] homologous [chromosomes] attach together to form [tetrads] (4 chromatids in a row) b)[Metaphase I] 23 [tetrads] line up along cell equator c)[Anaphase I] ** tetrads** (homologous chromosome pairs) separate and migrate to opposite poles i.e. 1 homologous chromosome (with 2 sister chromatids) goes to each pole sister chromatids DON'T separate d)[Telophase I] Identical steps to Telophase of mitosis but with 23 replicated chromosomes instead of 46. After **Meiosis I** and **cytokinesis**: each new cell has 23 different chromosomes (half the number of chromosomes) = **haploid (n)** these cells [DO NOT have] homologous chromosomes each cell has a single copy of each autosomal chromosome and a single sex chromosome 2)[Meiosis II] -- is the same as mitosis except it starts with 23 chromosomes instead of 46 a)prophase II b)metaphase II -- 23 replicated [chromosomes] line up at equator c)anaphase II -- sister chromatids split and 23 [chromosomes] migrate to each pole d)telophase II cytokinesis -- is the same as for mitosis/meiosis I (begins in anaphase/anaphase I/anaphase II, and continues through telophase/telophase I/telophase II) **Mitosis** **Meiosis I** **Meiosis II** **Prophase** **PI** Tetrads form **PII** **Metaphase** 46 chromosomes line up at equator **MI** 23 tetrads line up at equator **MII** 23 chromosomes line up at equator **Anaphase** kinetochores split & 46 chromosomes migrate to each pole **AI** Tetrads split & 23 replicated chromosomes migrate to each pole **AII** kinetochores split, sister chromatids separate and 23 chromosomes migrate **after cytokinesis** = interphase 2 identical diploid cells 23 pairs of chromosomes in each = 46 in total **after cytokinesis** 2 haploid cells 2 nearly identical copies of each of 23 chromosomes with sister chromatids **after cytokinesis** = gametes 4 haploid cells 1 copy of each of 23 chromosomes E\) Why Meiosis? Need to turn diploid germ cells into haploid gametes (ova/sperm) 23 Chromosomes from haploid (n) sperm cell combine with 23 chromosomes from haploid ovum (n) to form a single 46 chromosome cell called a zygote (2n) *UNIT 5: EARLY HUMAN DEVELOPMENT* **A) Pre-embryonic period = first 2 weeks** =========================================== 1. - - 2. - - 3. - a. b. - c. - - - - a. - i. ii. b. - - **B) Embryonic period = 3^rd^ week to end of the 8^th^ week** ============================================================= - 1. - 2. - 3. - - - - - - 1. - - - 2. - - 3. - - 4. - **C) Fetal period = 9^th^ week to end of 40^th^ week** ====================================================== - *UNIT 6: GENETICS* **A) Inheritance/Heredity** =========================== - - - 1. 2. - - 1. - - - 2. - - - - - - - - - - - - - - - - - - **B) Predicting Inheritance** ============================= - - - - Parents B B --------- --- --- b b - - - Parents B b --------- --- --- B b - - - - - - - **C) X-linked Inheritance** =========================== - - - - - XX = homologous - - - - +-----------------------+-----------------------+-----------------------+ | [Genotype]{.underline | [Phenotype]{.underlin | [Description]{.underl | | } | e} | ine} | +=======================+=======================+=======================+ | X**^N^**X**^N^** | not colour blind | homozygous dominant | +-----------------------+-----------------------+-----------------------+ | X**^N^**X^n^ | not colour blind | heterozygous | | | | (carrier) | +-----------------------+-----------------------+-----------------------+ | X^n^X^n^ | colour blind | homozygous recessive | +-----------------------+-----------------------+-----------------------+ | X**^N^**Y | not colour blind | one copy of dominant | | | | allele | +-----------------------+-----------------------+-----------------------+ | X^n^Y | colour blind | one copy of recessive | | | | allele | | | | | | | | no gene on Y to mask | | | | recessive gene on X | +-----------------------+-----------------------+-----------------------+ - Parent 1 -- ---------- ---------- --- Gametes X^n^ Y X**^N^** X^n^ *UNIT 7: HISTOLOGY (TISSUES)* **A) Histology?** ================= - - - - - 1. 2. 3. 4. **B) Cell Junctions [ ] (in some tissues)** ======================================================= - - - 1. - - - - 2. - 3. - - - - - **C) 4 Major Tissue Types (Overview)** ====================================== 1. - 2. - 3. - 4. - sensation and signalling tissue **D) Epithelial Tissue** ======================== - - - - - - - - - - - - 1. the number of cell layers sitting on the basement membrane a. b. 2. shape of the cells in the apical layer (= layer touching the free surface) c. d. e. - 1. - - a. - b. - c. - 2. - - - 3. - - 4. - - 5. - - d. - - i. - - - ii. - - e. - - - - 1. - - 2. - - 3. - - **E) Connective Tissue (CT)** ============================= - - - - - - - - - - - - - 1. - - - 2. - - 1. - - a. i. - - - ii. - - - b. - - - - i. - - - ii. - - 2. - - f. g. - - h. - i. - j. - - 3. - - k. l. - - - 4. - - m. n. **F) Muscle Tissue** ==================== - - 1. 2. 3. **G) Nervous Tissue** ===================== - 1. 2. **END OF MATERIAL FOR MIDTERM EXAM 1**