1. 3.What is the advantage of cells being small?
Materials move through cells by diffusion. Oxygen and food move into cells, while waste products move out of cells. How does the size of a cell affect how efficiently materials get to all parts of a cell?
Work with a partner to complete this activity
1. On a sheet of paper, make a drawing of a cell that has the following dimensions: 5 cm x 5 cm x 5 cm. Your partner should draw another cell about one half the size of your cell on a separate sheet of paper.
2. Compare your drawings. How much longer do you think it would take to get from the cell membrane to the center of the big cell than from the cell membrane to the center of the smaller cell?
3.What is the advantage of cells being small?
It would take twice the amount of time.
If cells are small, materials can be distributed to all parts of the cell quickly.

2. CELL GROWTH & DIVISION 10-1 & 10-2
Image from:
CELL GROWTH
& DIVISION
10-1 & 10-2
Image by Riedell

3. 2 Reasons why cells divide
DNA OVERLOAD
1. _____________________ As cell grows bigger demand on DNA “genetic library” becomes too great
Ex: Small town library has 1000 books.
As town grows and more people borrow books, there may be a waiting list to read the most popular titles

4. 2 Reasons why cells divide
Material exchange can’t keep up
2. _____________________ As cell grows bigger demand for transport across membrane is too great

5. Need for these depends on ___________
Ability to transport of oxygen, food, waste across cell membrane depends on _______________
Need for these depends on ___________
SURFACE AREA
CELL VOLUME
As cell grows these DON’T increase at the same rate
See relationship between volume and SA

6. Ratio of Surface Area to Volume in Cells
Section 10-1
Cell Size
Surface Area (length x width x 6)
Volume
(length x width x height)
Ratio of Surface Area to Volume

7. BIGGER CELLS NEED MORE FOOD and OXYGEN, but CAN’T TRANSPORT
IT FAST ENOUGH or IN BIG
ENOUGH QUANTITIES!

8. mainly by increasing cell number
Image from:
Image by Riedell
Multicellular organisms grow
mainly by increasing cell number

9. DNA CAN BE: SPREAD OUT IN NON-DIVIDING CELLS SCRUNCHED UP
IN DIVIDING CELLS
CHROMATIN
CHROMOSOMES

10. DNA in PROKARYOTES BACTERIAL DNA is CIRCULAR HAVE ONE CHROMOSOME
NO NUCLEUS; ATTACHED TO CELL MEMBRANE

11. DNA in EUKARYOTES (Plants & Animals)
DNA is ROD-SHAPED CHROMOSOMES
MANY PAIRS
FOUND IN NUCLEUS

12. Chromosome structure CHROMATIDS CENTROMERE HOMOLOGOUS
___________________ identical arms
__________________
constricted area holds chromatids together
CENTROMERE
HOMOLOGOUS
__________________ PAIR
2 of each chromosome (one from mom; one from dad)

13. HOMOLOGOUS CHROMOSOMES
SAME SIZE
SAME SHAPE
CARRY GENES for the SAME TRAITS
BUT ______________!
(Don’t have to have the SAME CHOICES)
NOT IDENTICAL

14. CELL DIVISION in PROKARYOTES
Bacteria reproduce using
__________________________________
BINARY FISSION

15. CELL CYCLE
______________ = series of events that cells go through as they grow and develop
cells alive cell cycle

16. CELL CYCLE INTERPHASE – non-dividing phase
G1- Grow bigger Cell is “doing its job” DNA is spread out as chromatin
S - Synthesis (copy DNA) & chromosomal proteins
G2- Grow bigger, make organelles & molecules needed for cell division

17. CELL DIVISION MITOSIS – Nuclear division Prophase Metaphase Anaphase
Telophase
Cytokinesis – Cytoplasm divides
G0 – cell stops dividing (Ex: nerve cell)

18. Figure 10–4 The Cell Cycle Section 10-2 G1 phase M phase S phase

20. INTERPHASE (G1 - S - G2) Can’t see chromosomes
In between divisions Cells are in this phase most of the time
Can see nucleus
DNA spread out as chromatin
Can’t see chromosomes
DNA gets copied (S)
Cell gets ready to divide

21. PROPHASE 1st dividing phase DNA scrunches into chromosomes
Pearson Education Inc publishing as Pearson Prentice Hall
PROPHASE
1st dividing phase
DNA scrunches into chromosomes
Centrioles appear in centrosome region & move to poles
Nuclear membrane & nucleolus disappear
Spindle fibers form & attach to chromosomes

22. ________ region organizes spindle
CENTROSOME
Spindle MICROTUBULES are part of cytoskeleton

23. METAPHASE Chromosomes line up in ___________ middle
Images from: Pearson Eduction Ince; Publishing as Pearson Prentice Hall

24. ANAPHASE Centromeres split Centrioles pull chromatids_______ apart
Images from: Pearson Eduction Ince; Publishing as Pearson Prentice Hall

25. two TELOPHASE (reverse prophase steps) See ______ nuclei
Nuclear membrane & nucleolus return
Chromosomes spread out as chromatin
Centrioles disappear
Spindle fibers disappear
Images from: Pearson Eduction Ince; Publishing as Pearson Prentice Hall

26. CYTOKINESIS Cytoplasm splits into 2 cells CLEAVAGE FURROW
ANIMAL CELLS pinch cytoplasm in two
with a ______________________
CLEAVAGE FURROW

27. CYTOKINESIS Cytoplasm splits into 2 cells
PLANT CELLS can’t pinch because
they have a sturdy ____________
Plant cells separate cytoplasm by growing a _______________ down the middle.
CELL WALL
CELL PLATE

28. Figure 10–5 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Chromatin
Centromere
Nuclear envelope
Centriole
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Telophase
Individual chromosomes
Anaphase
Nuclear envelope reforming

29. Figure 10–5 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Chromatin
Centromere
Nuclear envelope
Centriole
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Telophase
Individual chromosomes
Anaphase
Nuclear envelope reforming

30. Figure 10–5 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Chromatin
Centromere
Nuclear envelope
Centriole
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Telophase
Individual chromosomes
Anaphase
Nuclear envelope reforming

31. Figure 10–5 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Chromatin
Centromere
Nuclear envelope
Centriole
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Telophase
Individual chromosomes
Anaphase
Nuclear envelope reforming

32. Figure 10–5 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Chromatin
Centromere
Nuclear envelope
Centriole
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Telophase
Individual chromosomes
Anaphase
Nuclear envelope reforming

33. Figure 10–5 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Chromatin
Centromere
Nuclear envelope
Centriole
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Telophase
Individual chromosomes
Anaphase
Nuclear envelope reforming

34. Videos
Animal Cell Mitosis
Animal Cell Cytokinesis

35. Concept Map Cell Cycle Section 10-2 includes is divided into

36. Concept Map Cell Cycle Section 10-2 includes M phase (Mitosis)
Interphase
is divided into
is divided into
G1 phase
S phase
Prophase
G2 phase
Metaphase
Telophase
Anaphase

37. SOUTH DAKOTA CORE SCIENCE STANDARDS
LIFE SCIENCE: Indicator 1: Understand the fundamental structures,
functions, classifications, and mechanisms found
in living things
9-12.L Students are able to relate cellular functions and processes to specialized structures within cells.
Transport (ANALYSIS)
cell membranes, homeostasis
Cell life cycles (ANALYSIS)
Examples: somatic cells (mitosis)

38. Core High School Life Science Performance Descriptors
High school students performing at the
ADVANCED level:
predict the function of a given structure;
predict the outcome of changes in the cell cycle;
predict how homeostasis is maintained within living systems;
PROFICIENT level:
describe the relationship between structure and function
explain how homeostasis is maintained within living
systems;
compare and contrast the cell cycles in somatic and germ cells;
BASIC level
recognize that different structures perform different functions
define homeostasis;
describe the life cycle of somatic cells;