Anatomy and Physiology Flashcards

Week 2: Introduction to Anatomy and Physiology

Learning Objectives

• Identify anatomical position and use it to describe anatomical locations.

• Know major body planes and recognize views created by each.

• Look up anatomical nouns and adjectives for external body areas and understand their references.

• Apply anatomical terminology to body regions.

• Locate major body cavities.

• List major organs and identify at least two physiological roles for each of the 11 human organ systems.

• Identify each organ in the anatomical model and know its location within the model body.

• Understand how a microscope changes and distorts an image.

• Convert a visual image from a slide into an accurate but simplified line drawing.

• Identify major eukaryotic animal cell organelles and their functions.

• Understand and describe the Central Dogma of Biology and gene expression: DNA Replication, RNA transcription, and protein synthesis.

Body Cavities

• Dorsal Body Cavity:

  • Cranial cavity: Contains the brain.

  • Vertebral cavity (or spinal cavity): Contains the spinal cord.

• Ventral Body Cavity:

  • Thoracic cavity: Contains the heart and lungs.

    • Pleural cavity

    • Pericardial cavity: Mediastinum encloses pericardial cavity, esophagus, trachea, etc.

  • Abdominal cavity: Contains digestive viscera.

  • Pelvic cavity: Contains urinary bladder, reproductive organs, and rectum.

  • Abdominopelvic cavity: Combination of abdominal and pelvic cavities, separated by the diaphragm.

Serous Membranes

• Thin, double-layered membranes that produce a thin, lubricating fluid. Allows visceral organs to slide over each other or rub against the body wall with little friction.

• Parietal layer: Lines the cavity.

• Visceral layer: Covers the organ.

• Examples:

  • Pleura: Associated with the lungs.

    • Parietal pleura lines the thoracic cavity.

    • Visceral pleura lies directly on the surface of the lungs.

  • Pericardium: Associated with the heart.

    • Parietal pericardium forms a tough, outer sac, also called the pericardial sac.

    • Visceral pericardium is fused directly to the surface of the heart, also called the epicardium.

  • Peritoneum: In the abdominopelvic cavity, encases the abdominal and pelvic organs.

    • Parietal layer lines the abdominopelvic cavity.

    • Visceral layer lies directly on the surface of the internal organs.

  • Mesentery: Folds of peritoneum, suspends and attaches organs to body wall.

Mesentery

• Functions:

  • Holds organs in place.

  • Contains fat as stored energy.

  • Provides a place for blood vessels, nerves, and lymph vessels to reach organs.

• Types:

  • Mesocolon: A dorsal mesentery that anchors the large intestine to the parietal peritoneum of the dorsal body wall.

  • Greater Omentum: A large mesentery attached to the greater curvature of the stomach, covers the small intestine, and wraps dorsally to help anchor the intestines and the spleen to the dorsal body wall, then blends with the mesocolon. It contains fat and lymph nodes.

• Retroperitoneal: Organ outside the peritoneum

Human Torso Model: Organs

• Brain

• Lung

• Heart

• Diaphragm

• Liver

• Gall bladder

• Stomach

• Transverse colon

• Ascending colon

• Cecum

• Descending colon

• Small intestine

• Spleen

• Kidney

• Ureter

• Urinary bladder

• Esophagus

• Aorta

• Pancreas

• Urethra

• Thyroid gland

• Larynx

• Adrenal gland

• Bronchus

• Greater omentum (not on this model – a mesentery over the intestines).

Microscopy and The Cell

• Microscopy is the use of microscopes.

Use of the Microscope

Parts of a Microscope

• Eyepiece: 10X lens.

• Revolving nosepiece: Holds objective lenses.

• Objective lenses:

  • Red: 4X scanning.

  • Yellow: 10X, low power.

  • Blue: 40X high power.

• Stage: Platform to hold the slide.

• Condenser: Focuses light onto the specimen.

• Diaphragm: Controls the amount of light passing through the specimen.

• Light source: Provides illumination.

• Condenser knob: Adjusts the condenser.

• Base: Supports the microscope.

• Fine adjustment knob: Used for fine focusing.

• Coarse adjustment knob: Used for initial focusing.

• Arm: Connects the head to the base.

Field of View

• Diameter of the circle of light seen when looking into a microscope.

• As magnification increases, the field of view decreases.

Image Properties

• Image becomes inverted and upside down under a compound light microscope.

• When magnification increases:

  • Object appears larger.

  • Field of view gets smaller.

Microscope Setup

1. Plug in microscope and turn on the light source.

2. Carry the microscope by the arm, positioning it with the open side of the stage facing you.

3. Rotate the objectives so that the lowest power objective (smallest in size) clicks into place.

4. Look at the slide with your naked eye and find the location of the specimen.

5. Clip the slide into place with stage clips, ensuring the coverslip is face up. Ensure the stage controls move the slide smoothly.

6. Use stage controls to move the slide so the light source shines directly onto the specimen to be magnified.

7. Use the coarse focus knob to bring the low power objective as close to the slide as it will go, while watching the stage and objective.

8. Put your eye to the eyepiece and rotate the coarse focus knob in the lowering direction until some aspect of the specimen comes into focus.

9. Move your hand to the fine focus knob and get the specimen into perfect focus for your eyes. Do NOT touch the coarse focus knob again.

10. Use the stage control knobs to move your specimen close to the exact center of your field of view.

11. Move to the next highest power objective (do not skip individual objectives) and use only the fine focus to get your image into perfect focus for your eyes.

12. If you need further magnification, move to the next highest power objective and use only the fine focus to get your image into perfect focus for your eyes.

13. Do not use the 100x objective (if you have one) in this course. It must be used with immersion oil and we won’t have students doing that.

Cytology and the History of Cell Theory

• Cytology: Study of cells.

• 1665: Robert Hooke used a microscope to examine cork and coined the term "cells".

• Antonie van Leeuwenhoek (1632-1723): Observed "animacules" (living creatures) using the first microscope.

• 1838: Matthias Schleiden (German Botanist) stated that all plants are composed of cells.

• 1838: Theodor Schwann (German Physician) discovered that animals were made of cells.

• 1855: Rudolf Virchow (German Physician) stated that cells only come from other cells.

• 1855: Robert Remak (German Physician) stated that “pathological tissues are…the progeny or products of normal tissues in the organism”.

Cell Theory

• Combined work of Schleiden, Schwann, and Virchow:

  • The cell is the basic unit of structure and organization in organisms.

  • All living things are composed of cells.

  • Cells arise from pre-existing cells.

Cell Diversity

• Cells within the same organism show enormous diversity in size, shape, and internal organization.

  • Epithelial tissue: Lines surfaces in the body.

  • Muscle tissue: Made up of fibers that contract.

  • Nervous tissue: Consists of cells with projections that transmit electrical signals.

  • Connective tissues:

    • Loose connective tissue: Acts as padding under skin and elsewhere.

    • Bone and cartilage: Made up of cells in a hard or stiff extracellular matrix.

    • Blood: Connective tissue made up of cells in a liquid matrix.

Generalized Cell

• Cells have many structures in common, but also special adaptations to perform their functions. The "generalized" cell helps us learn structures that may be present in any one cell.

• No cell has all the structures of this "generalized" cell.

Parts of The Cell

• Ribosome: Protein factory.

• Plasma membrane: Regulates transport in and out of the cell.

• Golgi Apparatus (Body): Packages cell secretions.

• Centriole: Cell division.

• Centrosome: Cell division.

• Chromatin (DNA): Heredity.

• Nucleolus: Makes RNA, ribosomes.

• Nuclear envelope (membrane).

• Rough endoplasmic reticulum: Channels with ribosomes.

• Cytosol: Cytoplasmic fluid.

• Nucleus: Control center of cell.

• Mitochondrion: Produces energy for the cell, "powerhouse of the cell".

• Lysosome: Contains digestive enzymes.

• Pinocytotic vesicle brings in extracellular fluids

• Storage vacuole membranous sac to store nutrients

• Nuclear pore

• Primary cilium senses extracellular conditions such as fluid movement, chemicals, temp. and involved in many diseases.

The Central Dogma of Biology

• Central Dogma: Describes the flow of genetic information within a biological system.

  • Includes (DNA) Replication, Transcription (DNA>RNA), and Translation (RNA>Protein)

DNA

• Coded instructions for proteins.

• Gene: A specific piece of DNA that encodes a functional protein.

• Gene Expression: The process by which a gene gets turned on in a cell to make RNA and proteins.

• Segment of DNA with blueprint for one polypeptide

• Triplets (three sequential DNA nitrogen bases) form genetic library – Bases in DNA are A, G, T, and C – Each triplet specifies coding for number, kind, and order of amino acids in polypeptide

• Gene Expression = Protein Synthesis

DNA Structure

• Composed of nucleotides.

• Nitrogenous bases: Adenine (A), Guanine (G), Cytosine (C), Thymine (T).

• Base pairs:

  • A pairs with T.

  • C pairs with G.

• Sugar-phosphate backbone.

• Double helix structure with major and minor grooves.

DNA Replication

• Two identical DNA molecules are formed from the original.

• Semiconservative replication: Each DNA molecule is composed of one old and one new strand.

Protein Synthesis Overview

• Occurs in two steps:

  • Transcription: DNA information is coded in mRNA.

  • Translation: mRNA is decoded to assemble polypeptides.

• Genes are composed of exons and introns:

  • Exons code for amino acids.

  • Introns are noncoding segments.

• Role of RNA:

  • DNA decoding mechanism and messenger.

  • Three types–all formed on DNA in nucleus:

    • Messenger RNA (mRNA).

    • Ribosomal RNA (rRNA).

    • Transfer RNA (tRNA).

• RNA differs from DNA:

  • Uracil (U) is substituted for thymine (T).

Transcription

• Transfers a DNA gene base sequence to a complementary base sequence of mRNA.

• Transcription factors: Gene activators.

  • Loosen histones from DNA in the area to be transcribed.

  • Bind to the promoter - DNA sequence specifying the start site of the gene on the template strand.

  • Mediate binding of RNA polymerase (enzyme synthesizing mRNA) to promoter.

• Transcription: Instructions for protein production.

• There are three stages to trancription: Initiation, Elongation, and Termination.

Translation

• mRNA is decoded to assemble polypeptides

Genetic Code

• Each three-base sequence on DNA (triplet) is represented by a codon.

• Codon: Complementary three-base sequence on mRNA.

• Some amino acids are represented by more than one codon.

Translation: Initiation

• Small ribosomal subunit binds to initiator tRNA and mRNA to be decoded; scans for start codon.

• Large and small ribosomal units attach, forming functional ribosome.

• At the end of initiation:

  • tRNA is in the P site.

  • A site is vacant.

Translation: Elongation

• Three steps:

  • Codon recognition: tRNA binds complementary codon in A site.

  • Peptide bond formation: Amino acid of tRNA in P site is bonded to the amino acid of tRNA in A site.

  • Translocation: tRNAs move one position–A à P; P à E.

Translation: Termination

• When a stop codon (UGA, UAA, UAG) enters the A site:

  • Signals the end of translation.

  • Protein release factor binds to stop codon -> water added to chain -> release of polypeptide chain; separation of ribosome subunits; degradation of mRNA.

  • Protein processed into functional 3-D structure.

Protein Folding and Degradation

• Damaged/misfolded proteins can lead to cell damage and death, major contributors to aging and disease.

• Chaperone-mediated refolding: Chaperones help proteins fold correctly.

• Unfolded/damaged protein is degraded via the Ubiquitin-proteasome system or Autophagy.

• Protein aggregates can have cytotoxic effects.

Important Terms and Structures

Body Cavities and Organs

• Thoracic cavity

• Abdominopelvic cavity

• Pleural cavity

• Pericardial cavity

• Peritoneal cavity

• Serous membranes

• Visceral pleura/pericardium/peritoneum

• Parietal pleura/pericardium/peritoneum

• Adrenal gland

• Aorta

• Ascending colon

• Brain

• Bronchus

• Cecum

• Cranial cavity

• Descending colon

• Diaphragm

• Esophagus

• Gall bladder

• Greater Omentum

• Kidney

• Heart

• Larynx

• Liver

• Lung

• Pancreas

• Small intestine

• Spleen

• Stomach

• Thoracic Cavity

• Thyroid gland

• Trachea

• Transverse colon

• Ureter

• Urethra

• Urinary Bladder

Cellular Organelles

• Mitochondria

• Peroxisomes

• Lysosomes

• Smooth Endoplasmic reticulum

• Rough Endoplasmic reticulum

• Golgi apparatus

• Vesicles

• Nucleus

• Nuclear membrane

• Nuclear pore

• Nucleolus

• Chromatin

• Ribosomes

• Centriole

• Centrosome

• Cytosol

• Cytoskeleton

• Cell membrane

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Gene Expression

• Transcription

  • RNA polymerase

  • Nucleotides -> mRNA

• Translation

  • mRNA

  • tRNA

  • rRNA

  • Amino acids -> proteins

  • Ribosome, small subunit

  • Ribosome, large subunit

  • Codon

  • Anticodon

Parts of the Microscope

• Eyepiece

• Arm

• Coarse adjustment

• Fine adjustment

• Base

• Revolving nosepiece

• Objective lenses

• Stage

• Condenser

• Diaphragm

• Light source

• Field of view