CHAPTER 3 CELLS
Cells are the next level of organization after atoms, molecules, macromolecules, & organelles . They are the basic structural & functional unit of life. Each cell is made of organelles which are made of large molecules.
Pay particular attention to Chart 3.2 in the text that lists the various organelles & their functions. A thorough knowledge of these organelles will help you to understand the physiology of each of the organs studied in both semesters of A&P.
Pay particular attention to figures 3.1, 3.2, 3.3. Notice that cells differ in SIZE, SHAPE, and FUNCTION.
FUNCTION of cell is directly related to SHAPE of cell. Learn figure 3.3 in detail.
I. Cells are made of a nucleus, cytoplasm, organelles and a cell membrane
A. Nucleus
1. Controls the overall ________________________________________________
2. Called _________________________________________________
3. Contains the _____________________________ of the cell (the genetic code)
B. Cell membrane Fig. 3.7 ******
1. Outermost __________________________ of living material
2. Selectively ___________________________________________: controls
movement of substances between cell & surroundings
3. Made of a ________________________________________________________
that contains protein, carbohydrate, & cholesterol
4. Phosphate heads are _____________________________________(_________)
5. Fatty acid tails are ______________________________________ (_________)
6. Molecules soluble in ________________________ pass through the membrane
easily; _________________________________________ molecules do not.
7. Molecules of cholesterol help to make the membrane _____________________.
8. Proteins: account for special functions of membrane.
a. Rod like proteins act as ______________________________on cell surfaces�
for what?
b. Globular proteins form _______________________________ for passage of
ions & molecules
c. CAMs: cell adhesion molecules; help guide moving cells; Page 68, 69
9. Cell membrane is known as a fluid mosaic
a. Not solid & rigid
b. Similar to semi-liquid jello
c. Be able to draw or label the cell membrane in Fig. 3.7
C. Connections between cells Fig. 3.8 & Chart 3.1
1. Tight junctions: _______________ cell membranes together; prevent leakages;
found in cells that line the inside of the small intestine
2. Desmosomes: ____________ cells together; form spot welds; found on outer
skin layer
3. Gap junctions: form tubular ___________________________ between cells;
substances can be exchanged between cells; found in muscles
of heart & digestive tract
D. Cytoplasm: contains networks of membranes & organelles suspended in fluid
1. Endoplasmic reticulum see Fig. 3.10
a. Organelle made of interconnected membranous sacs, canals, & vesicles
b. Forms a ___________________________________________________ for
the cell; communicates with cell membrane, nuclear membrane & organelles
c. Forms an attachment for ribosomes � _________________ site of protein syn
d. Smooth ER�lacks ribosomes � site of ________________ synthesis and
hormone synthesis
e. ER produces new membrane which moves to golgi apparatus, becomes a
vesicle & moves to become part of cell membrane
2. Ribosomes
a. Particles of protein & RNA found on ER & loose in the cytoplasm
b. Function in ________________________________ synthesis
3. Golgi apparatus � see Fig. 3.11
a. Stack of flat, _________________________________________________
b. Functions to package glyco_________________________ for secretion
4. Mitochondria � ~2000 in each cell; passed on only by the mother; see Fig. 3.13
a. Long, membranous sacs full of enzymes
b. Has 2 layered membrane: inner membrane folded to form ______________
c. Stalked particles containing __________________________ found on cristae
d. Enzymes function to release ______________________ from food molecules
e. Transform that energy into usable forms
f. Mitochondria able to _______________________ by dividing & can move in
the cytoplasm
g. Contain small amts of ________________ for making new kinds of proteins,
specialized RNA
See box on page 71 for some interesting info on mitochondria
5. Lysosomes � garbage can containing 40+ enzymes
a. Membranous sacs full of _____________________________ enzymes
b. Destroy bacti, etc. that enter cell
c. Destroy worn out parts of cell
6. Peroxisomes
a. Membranous sacs full of 40+ enzymes
b. Decompose _________________________ (toxic to humans) with catalase
c. Involved in breakdown of ________________
d. Involved in detoxification of ____________________
7. Centrosome Fig. 3.15
a. Nonmembranous structure
b. Made of two centrioles
c. Aids in distribution of chromosomes during cell reproduction
8. Cilia Fig. 3.16
a. Tiny, waving, ___________________________________ on cell membrane
b. Made of __________________________________________ arranged in
cylindrical pattern
c. Attached beneath cell membrane to basal body (a modified centriole)
d. Move fluids across cell surfaces
e. Move nutrients, waste products, mucus
9. Flagella Fig. 3.17
a. Long process of __________________________________
b. Made of microtubules arranged in cylindrical pattern
c. Responsible for _________________________________________ of cells
10. Vesicles
a. __________________________________________ sacs
b. Contain substances that enter cell or products produced in cell
11. Microfilaments Fig. 3.18, 3.19
a. Thin rods of ______________________ (actin) arranged in meshwork or
bundles
b. Aid in ______________________ of cells; responsible for movement of
muscles
12. Microtubules Fig. 3.18, 3.19
a. Tubes made of __________________________________ (tubulin)
b. Stiff, form the _________________________________________ ==
maintain shape of cell
c. Interact to form movement in cilia & flagella
d. Move chromosomes to newly forming cells
13. Nucleus � governing body Fig. 3.20
a. Enclosed in double-layered nuclear ______________________________
with pores
b. Contains nucleolus: dense body of protein & RNA that produces ribosomes
c. Contains chromatin: coiled fibers of protein & DNA that become
chromosomes during cell reproduction
d. Known as _________________________________________________ of
the cell
Can you draw a typical nucleus?
14. Nucleolus � little nucleus
a. Located in nucleus
b. Has no membrane
c. Site of _______________________________________________production
15. Chromatin: DNA molecules wrapped around clusters of 8 molecules of histones
a. Loosely coiled fibers
b. Form _________________________________________ during reproduction
What is apoptosis?
Helpful Activities to do after you finish reading this chapter
1. Exercises - 3 and 5 in your lab book
2. Crossword puzzle on Cellular vocabulary
3. Check out the following web site: