Intro to the Cell

Why do we have to learn about the cell?? Damage to cell disrupts function To understand dysfunction you much

understand function! Science discovers new disease all the time!

Examples:

Exercise Induced Collapse

Diseases at the cellular level (especially mitochondria)-ALS, Bipolar disorder, Alzheimer's disease

We must remember our patients cells when we are treating them in our clinics!

Introduction

Cell=“little chamber” Functional units of the body Cells come together to form tissues Cell=60-65% water Intracellular fluid (40% BW vs.

Extracellular fluid (20% BW)

Functions of cells

Reproduction Absorption Metabolism

Anabolism vs. Catabolism Excretion Secretion Contractility Conduction Irritability/excitability

Functions of cells

Reproduction-duplicate oneself Absorption-taking dissolved materials/water into cell Metabolism-physical/biochemical reactions within

cell Anabolism vs. Catabolism

Secretion-excrete products Contractility-ability to shorten in one direction Conduction-transmitting an electrical impulse Irritability/excitability-being able to react to an

impulse

Terminology

Increase in cellular size Hypertrophy Increase in cellular numberHyperplasia Decrease in cellular size Atrophy Failure to develop Aplasia Incomplete development Hypoplasia Abnormal development Dysplasia Homeostasis

Components of a Cell

Cell membrane Cytoplasm

Metabolites Cytoskeleton Organelles

Nucleus

Cell Membrane Lipid bilayer!

Controls passage Protein - pores

Cell Membrane-movement Passive - Diffusion,

facilitative diffusion-osmosis

Active - Requires ATP, voltage gated

Phagocytosis - engulfment

Pinocytosis - contact mediated….fluid

Osmosis

What effect would each of the following solutions have on a normal cell?

Isotonic solution Hypertonic solution Hypotonic solution

Cell membrane-special modifications Cilia-9+2 arrangement Flagella

Where do we find these?? Glycocalyx-”fingerprint”

Cytoplasm

Inner part of cell excluding nucleus Cytosol

Dissolved electrolytes, AA, sugars and enzymes Cytoskeleton

Framework Microtubules-”train track” for organelles Intermediate fibers-resist pulling forces Microfilaments-helps cell change shape

Actin/myosin**Muscle, cell division

Organelles-Mitochondria

“Powerhouse” of the cell!DNA and RNA distinct from rest of

cell??? Glucose ATP via TCA cycle Respiration occurs

O2/CO2 exchange Amino acids and Fatty acid

catabolism More active cells-more

mitochondria Which cells???

Mitochondrial Function-TCA and Respiration

Organelles-Ribosomes

Site of Protein Synthesis Moves to where protein needs to be synthesized Assembles amino acids in accordance with

genetic code

Transcription vs. Translation???

Organelle-Endoplasmic Reticulum Continuous membrane with Nucleus and

Golgi apparatus Rough ER-ribosomes attached

Modify proteins made by ribosomes Smooth ER-lipid synthesis and storage

Phospholipids and steroid hormones High levels in glandular tissue

ER

Organelle-Golgi apparatus

Protein Modifying Packaging Distribution center

Organelles-lysosomes Special vesicles formed by Golgi Hydrolytic enzymes

Bacteria, Fungi, etc. Cell Death

“Autolysis”

Peroxisomes-not produced by Golgi-cell division. Found in the liver and kidney Detoxify (alcohol and formaldehyde), remove free

radicals (convert them to H202, then to H20)

Nucleus=“Brain” of the Cell

Maintains hereditary info of species Controls cell activity via protein synthesis

(over 2000 proteins) Cell division-produce identical daughter cells

Multinucleate vs.

Anucleate?

Nucleus

Chromatin= DNA wrapped around histones (gene regulation) Tight coils – inactive cell

Chromosomes-Condensed chromatin during cell division-Dense DNA/histones very active cell

Nucleoli- Multiple spherical patches within chromatin Produce ribosomal subunits/rRNA

Nucleoli

This workforce solution was funded by a grant awarded under the Workforce Innovation in Regional Development (WIRED) as implemented by the U.S. Department of Labor’s Employment and Training Administration working in partnership with the Colorado Department of Labor and Employment, the Metro Denver Economic Development Corporation, and the City and County of Denver's Office of Economic Development.  The solution was created by the grantee and does not necessarily reflect the official position of the U.S. Department of Labor.  The Department of Labor makes no guarantees, warranties, or assurances of any kind, express or implied, with respect to such information, including any information on linked sites and including, but not limited to, accuracy of the information or its completeness, timeliness, usefulness, adequacy, continued availability, or ownership.  This solution is copyrighted by the institution that created it. Internal use by an organization and/or personal use by an individual for non-commercial purposes is permissible.  All other uses require the prior authorization of the copyright owner.