1. Anatomy and Physiology
Hole’s Human
Anatomy and Physiology
Eleventh Edition
Shier w Butler w Lewis
Chapter 3
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

2. Chapter 3: Cells Human body cells: 70 trillion cells
260 different types
eukaryotic
vary in size
possess distinctive shapes to fit their function
measured in micrometers

3. Cell Structure
3 major cell parts
nucleus
cytoplasm
cell membrane

4. Cell Membrane outer limit of cell
controls what moves in and out of cell
selectively permeable

5. Cell Membrane Composed maily of: phospholipid bilayer proteins
water-soluble “heads” form surfaces
water-insoluble “tails” form interior
permeable to lipid (nonpolar)-soluble substances
proteins
receptors
self-markers
transport

6. Cytoplasmic Organelles
Endoplasmic Reticulum
connected, membrane- bound sacs, canals, and vesicles
transport system
rough ER
studded with ribosomes
protein synthesis
smooth ER
lipid synthesis
break down of drugs
Ribosomes
free floating or connected to ER
provide structural support

7. Cytoplasmic Organelles
Mitochondria
membranous sacs with inner partitions
generate energy
Golgi apparatus
stack of flattened, membranous sacs
modifies, packages and delivers proteins
Vesicles
membranous sacs
store substances

8. Cytoplasmic Organelles
Centrosome
two rod-like centrioles
distributes chromosomes during cell division
Lysosomes
enzyme-containing sacs
digest worn out cell parts or unwanted substances
Peroxisomes
enzyme-containing sacs
break down organic molecules

9. Cytoplasmic Organelles
Cilia
short hair-like projections
propel substances on cell surface
Flagellum
long tail-like projection
provides motility to sperm

10. Cytoplasmic Organelles
Microfilaments and microtubules
thin rods and tubules
support cytoplasm
allows for movement of organelles

11. Cell Nucleus control center of cell nuclear envelope nucleolus
porous double membrane
separates nucleoplasm from cytoplasm
nucleolus
dense collection of RNA and proteins
site of ribosome production
chromatin
fibers of DNA and proteins
stores information for synthesis of proteins

12. Movements Into and Out of the Cell
Passive Transport
require no cellular energy
simple diffusion
facilitated diffusion
osmosis
filtration
Active Transport
require cellular energy
endocytosis
exocytosis

13. Simple Diffusion
movement of substances from regions of higher concentration to regions of lower concentration
oxygen, carbon dioxide and lipid-soluble substances

14. Facilitated Diffusion
diffusion across a membrane with the help of a channel or carrier molecule
glucose and amino acids

15. Osmosis
movement of water through a selectively permeable membrane from regions of higher concentration to regions of lower concentration
water moves toward a higher concentration of solutes

16. Osmosis Comparing the outside environment to the inside of the cell
if both environments are of the same concentration of solute they are considered isotonic and will remain stable
if the outside solution has a higher solute concentration than it is hypertonic and the cell will shrink
if the outside solution has a lower solute concentration than it is hypotonic and the cell will swell

17. Active Transport
carrier proteins transport substances across a membrane from regions of lower concentration to regions of higher concentration
sugars, amino acids, sodium ions, potassium ions, etc.

18. Endocytosis
cell engulfs a substance by forming a vesicle around the substance
three types
pinocytosis – substance is mostly water
phagocytosis – substance is a solid
receptor-mediated endocytosis – requires the substance to bind to a membrane-bound receptor

19. Exocytosis reverse of endocytosis
substances in a vesicle fuse with cell membrane
contents released outside the cell
EX: release of neurotransmitters from nerve cells

20. The Cell Cycle
series of changes a cell undergoes from the time it forms until the time it divides
3 stages
interphase
mitosis
cytoplasmic division

21. Interphase very active period 2 phases
G phases – cell grows and synthesizes new organelles to prepare for cytoplasmic division
S phase – cell replicates DNA to prepare for nuclear division

22. Mitosis nucleus divides – karyokinesis cytoplasm divides – cytokinesis
produces two daughter cells from an original somatic cell
nucleus divides – karyokinesis
cytoplasm divides – cytokinesis
stages (PMAT)
prophase – chromosomes form; nuclear envelope disappears
metaphase – chromosomes align midway between centrioles
anaphase – chromosomes separate and move to centrioles
telophase – chromatin forms; nuclear envelope forms

23. Mitosis

24. Tumors Two types of tumors benign – usually remains localized
malignant – invasive and can metastasize; cancerous
Two major types of genes cause cancer
oncogenes – activate other genes that increase cell division
tumor suppressor genes – normally regulate mitosis; if inactivated they are unable to regulate mitosis
cells are now known as “immortal”

25. Stem and Progenitor Cells
Stem cell
can divide to form two new stem cells
self-renewal
can divide to form a stem cell and a progenitor cell
totipotent – can give rise to every cell type
pluripotent – can give rise to a restricted number of cell types
Progenitor cell
committed cell
can divide to become any of a restricted number of cells
pluripotent

26. Stem and Progenitor Cells

27. Clinical Application Diseases at the Organelle Level
MELAS – mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes
mitochondria are missing a gene necessary to carry out important energy producing reactions
usually inherited by mother
causes strokes, severe headaches, muscle weakness and numb hands
ALD – adrenoleukodystrophy
peroxisomes are missing enzymes
causes dizziness, weakness, darkening skin, and abnormal heart rhythms
Tay-Sachs Disease
lysosomes are abnormally large and lack one enzyme
causes nervous system failure and early death