Unit 1
The Power of
Reproduction
Chapter 1 – The Cell Cycle and
Asexual Reproduction
Amazing Cells
Animal Cell
Plant Cell
1.1 The Cell (Pages 4 – 16)
1.
2.
Scientists have long been fascinated with
life. After thousands of years of studying
it we still haven’t figured out how it
works. Some history:
Assignment:
a)
b)
c)
The Cell Question Sheet
Label Cell Diagrams (1-6 & 1-7)
Cell Structures Chart
Chapter 1.1 – The Cell Question
Sheet
1.
Record the date and contribution to cell
theory for the following scientists: (22)
a)
b)
c)
Aristotle (384-322 BC) – animal and plant
kingdom (animals higher, spontaneous
generation)
Zacharias Janssen (1590) – first
compound microscope
Robert Hooke (1665) – microscope –
referred to cells as “rooms”
Chapter 1.1 – The Cell Question
Sheet
1.
Record the date and contribution to cell
theory for the following scientists: (22)
a)
b)
John Ray (1667) – “species” organism
that reproduce with their own kind
Francesco Redi (1668) – disproved
spontaneous generation (flies and
maggots)
The Redi experiment
Replica of a Leeuwenhoek microscope
The following photomicrographs were taken
through a Leeuwenhoek microscope.
a)
b)
c)
d)
Anton van Leeuwenhoek (1632 – 1723) microscope
Robert Brown - nucleus is part of the cell
Schleiden/Schwann (1838/1839) – all
organisms are made of cells
Alexander Carl Heinrich Braun (1845) –
the cell is the basic unit of life
e)
f)
g)
Charles Darwin and Alfred Wallace –
species form variations
Rudolph Virchow (1821 – 1902) – cells
come from cells
Louis Pasteur (1860) – disproved
spontaneous generation at the
microscopic level (life comes from life)
Pasteur’s
swan neck
flask
experiment
1.
Like all sciences, biology has its own
set of tools, techniques, and
investigative methods. What tools
helped scientists develop the cell
theory? (3)
2.
What methods helped scientists
develop the cell theory? (2)
2.
What methods helped scientists
develop the cell theory? (2)
1. State a question
2. Form a hypothesis (educated guess –
what you think will happen)
3. Design an experiment
4. Make observations
5. Draw conclusions – answer hypothesis
4.
The internet was originally designed to
allow scientists all over the world to
communicate quickly and easily with
each other. What invention had a
similar effect on scientific
communication in earlier centuries?
(1)
5.
What can you conclude about the
relationships between scientific
discovery, tool inventions, and new
methods? (1)
6.
•
•
•
•
Cell theory states that: (4)
all living organisms are made up of one
or more cells
Cells are the basic unit of life
Cells come from cells
Activity of entire organism depends on
total activity of its independent cells
Animal Cell
Plant Cell
Assignment

BLM 1-5, 1-8, 1-9, 1-10, Investigation 1B
Cell Structures Chart
Cell Size and Scale
1. Nucleus



contains the cell’s genetic material
holds instructions for making/building the
cell
2. Nuclear Membrane


encloses the cells’ genetic material
contains the DNA
Cell Structures Chart
3. DNA
 Deoxyribonucleic Acid
4. Chromatin
 Long strands of DNA
5. Nucleolus
 dark area within the nucleus
 manufactures ribosome parts
Cell Structures Chart
6. Ribosomes
 contribute to the manufacture of proteins
7. Cell Membrane
 separates the contents of the cell from its
surroundings
 selectively permeable membrane that allows
only certain material in and out of the cell
Cell Structures Chart
8. Cytoplasm
 jelly-like material
 supports the nucleus and other organelles
9. Endoplasmic Reticulum
 a folded membrane that forms a series of
canals
 transports materials to different parts of the
cell (like our circulatory system)
Cell Structures Chart
10. Mitochondria
 transform energy for the cell (sugar to ATP)
 cellular respiration takes place here (this is
not in your text, please copy it)
11. Golgi Bodies
 package useful materials
 then it secretes them to the outside of the cell
(like our digestive system)
Cell Structures Chart
12. Vacuoles
 fluid filled store houses for water, waste and
nutrients (like our digestive system)
13. Lysosomes
 break down food and digest wastes and
worn out cell parts (like our digestive
system)
Cell Structures Chart
Plants Only
14. Cell Wall
 Provides structure and support for the cell
(acts like the cells’ skeleton)
15. Chloroplasts
 this is where photosynthesis takes place
 photo means “involving light” and “synthesis
means “to make”
BLM 1-5
Life Function
Body System
Cell Part(s)
Taking in nutrients and
using energy
Digestive System
Mitochondria
Eliminate wastes
Excretory System
Vacuole and lysosome
Control center
Nervous System
Nucleus
Building and repairing
body parts,
transporting nutrients
Circulation and
Digestion systems
ER, ribosomes and
golgi bodies
Contains genetic
information
Reproductive system
Nucleus
1.2 Understanding the Cell Cycle


Cells grow and then divide to make new
cells.
New cells are used to replace dead ones
OR for growth of the organism.
YOU started out as 1 cell!
 Before a cell can divide into 2 cells it must
produce almost twice as many organelles
(replication).
 A cell’s stages of life are called phases.






1. Interphase
Most of cell’s life
DNA in thin strands called Chromatin
replicate.
Chromatin coils up to form double
stranded Chromosomes.
A Centromere connects the original
chromatin with its identical replicate.
The cell has a complete extra copy of
DNA.
A Chromosome
2. Prophase
 Duplicate DNA is easily seen under
microscope.
 Nucleolus and Nuclear Membrane
disappear.
 Centrioles move to opposite sides of
the cell. (Fishing boats)
 Spindle fibres (like a scaffold) grow out
of each centriole and attach to
centromere. (Fishing line)
3. Metaphase
 Spindle fibres pull on centromeres
 Chromosomes move to line up in the
middle.
4. Anaphase
 Spindle fibres shorten and pull
centromere apart.
 One copy of DNA goes to each side.
5. Telophase




A complete set of chromosomes
arrives at each centriole.
Spindle fibres disappear.
Nuclear membrane and nucleolus
reform.
Chromosomes uncoil into thin
chromatin.
5. Telophase (cont’d)



Cell membrane pinches together in the
middle (cytokinesis)
Two cells form (animal cells).
A cell plate grows across the middle of
the cell forming a new cell wall
between the two cells. (plants)
Parent Cell
Daughter Cells
Phase 1:
Prophase
Phase 2:
Metaphase
Phase 3:
Anaphase
Phase 4:
Telophase
Mitosis Animation Clips
 http://www.pbs.org/wgbh/nova/miracle/divi
de.html#
 http://www.johnkyrk.com/mitosis.html
 organelles and mitosis
 In depth mitosis
 http://www.dnatube.com/video/2380/Interp
retive-Mitosis
Assignment
BLM’s 1-14, 1-15, 1-16 & 1-17
 Mitosis Crossword & Mitosis Chart
 Mitosis Quiz

1.3 The Cell Cycle in YOUR Body
Some common chromosome counts:
Dogs
Tomatoes
Humans
Black Molly (fish)
78
24
46
46
1. Normal Cell Replacement
a)
Cells die of old age and need to be
replaced. See pg 25 for cell life spans.
 about 3 billion cells die in your body every
minute.
b)
c)
Cells die due to damage or when they
don’t get enough food or oxygen.
Regeneration - Healing of damaged
tissue or the replacement of body parts is
called regeneration. (NOTE: see note
under Figure 1.17 – pg 26)
2. Growth
a)
b)
As organisms grow larger, their cells stay
the same size
They just get more of them.
3. Aging
1.
2.
Aging is connected to the slowing of the
cell cycle.
The cells do not divide as often or as
quickly.
Cancer is caused when the DNA of a
cell becomes damaged by
1.
a)
b)
c)
d)
e)
f)
Tobacco
Asbestos
Certain chemicals
some viruses
Radioactivity
UV radiation
The damage injures but does not kill the cell.
The cell no longer functions properly and the
DNA no longer has correct information about
when and how quickly to divide.
The result: Useless cells divide often and
quickly forming a lump.
If the cancer cells can easily be transported the
cancer can spread all over.
The lump crowds out good cells and use up a
lot of food and oxygen.
1.
2.
3.
4.
5.
•
Worksheet & Cancer Research
1.
Explain a process in the human body
in which there is evidence of the cell
cycle at work. (1)

Growth and development
2.




Give two reasons why cells die. (2)
Damaged
Programmed to live a certain amount of
time – no longer needed
Lack of food or oxygen
Failed mitosis
3.

How do scientists currently explain
the aging process? (2)
The cell cycle is slowing down
4.

Describe what happens when cells
divide uncontrollably. (2)
Cancer – these cells are like weeds in a
garden, choking out the healthy
plants/cells.
5.
Using your knowledge about
cancer and cell division, explain
how you think sunscreen can help
reduce the risk of skin cancer. (2)

It blocks the UV rays and prevents them
from damaging the genetic material
6. Some cells live for years, while
others live for only a few days.
Why do you think some cells
might be replaced faster than
others? (2)

Some cells are damaged more quickly
by their environments (stomach acid).
7.

The muscle cells of the heart were
once thought to stop dividing when a
person reached the age of nine. Thus,
heart attacks, which kill heart cells,
were believed to cause permanent
damage to the heart muscle. New
research has discovered that mitosis
does occur in the heart later in life.
What do you think this new discovery
means for people who have heart
attacks? (2)
Your body is capable of regenerating
heart cells – this gives heart attack
survivors hope for recovery
1. What happens to our cells to
bring about cancer? (2)

Cancer is a disease that starts in our cells.
Our bodies are made up of millions of
cells, grouped together to form organs or
tissues such as the lungs, the liver,
muscles and bones. Genes inside each
cell order it to grow, work, reproduce and
die.
2. What is a tumor/lump made
up of? (2)

Normally these orders are clear, our cells
obey and we remain healthy. Sometimes a
cell’s instructions get mixed up and
it behaves abnormally. After a while
groups of abnormal cells form lumps or
tumours.
3. What is the difference
between a benign and
malignant tumour? (2)


Tumours can be either benign (noncancerous) or malignant (cancerous).
Benign tumour cells stay in one place in
the body and are not usually lifethreatening.
Malignant tumour cells are able to
invade the tissues around them and
spread to other parts of the body.

Cancerous cells that spread to other
parts of the body are called metastases.


The first sign that a malignant tumour
has spread is often swelling of nearby
lymph nodes, but cancer can
metastasize to almost any part of the
body.

Malignant tumours can be dangerous.

It is important to find them and treat
them quickly, before they spread.
4. How are cancers named? (2)

Cancers are named after the part of the
body where they start.

For example, cancer that starts in the colon
but spreads to the liver is called colon cancer
with liver metastases.
1.4 Asexual Reproduction
- Bacteria, Protists, Fungi, and
Some Animals
Reproduction – the formation of
a new individual that has identical genetic
information to its parent.
 Asexual
Reproduction
Asexual
Sexual
Binary Fission
Budding
Conjugation
Spore Formation
Fragmentation
Hermaphroditic
Vegetative
Reproduction
Separate Sexes
Bacteria – see p 30
1.
2.
3.
Have no nuclear membrane
(prokaryotic)
Have only one chromosome
Reproduction asexually by the process
of binary fission.
1.
a)
b)
c)
d)
e)
steps:
cell wall ruptures
single chromosome gets copied
cell grows longer and a chromosome
moves to each end.
cell membrane pinches off.
cell wall grows to surround both cells.
Protists
1.
2.
3.
Ex) paramecium,
amoeba, euglena,
vorticella
unicellular organisms
with a true nucleus
(eukaryotic).
mitosis takes place
creating two identical
cells.
Fungi
1.
2.
Ex) Moulds, yeast, and mushrooms
filaments called hyphae grow over the
surface of food.
3.
a)
have 3 methods of asexual
reproduction
fragmentation – a small piece of hyphae
breaks away and grows into a new
individual. It is identical to its parent.
(fungi – p 32)
b)
•
budding – a copy of
the nucleus is made.
The nuclei press
against the cell
membrane, forming a
bud which grows and
breaks off. (yeast)
http://coralreefmultimed
ia.org/reef/shorts.pop?t
opic=Reproduction#
c)
spores – special cells called spores are
stored in a case called a sporangium.
The spores are released when ready and
go through mitotic cell division if they land
in suitable conditions. (bread mold – p
33)
Animals
1.
2.
3.
•
Invertebrates (without backbone) make
up 97% of animal species
Ex) Planaria (Flatworms) – divide in two
and replace the parts that are missing.
Ex) Sponges and hydras – reproduce by
budding. see pg 35.
READ p 29-34 and do questions 1 – 6.
1.5 Asexual Reproduction in
Plants
1.
2.
3.
Plants have an amazing ability to repair
themselves using mitosis.
They are often even able to regrow from
a stump.
Recall: asexual means DNA is exactly
the same as its parent.
Meristem
1.
2.
3.
4.
Animals stop growing at an adult size
Plants grow until they die.
Meristem – unspecialized cells in the stem
and root tips which undergo mitosis very
often.
Meristem cells divide and promote growth at
the stem and root tips.
Meristem (cont’d)
1.
At some point some meristem cells
specialize to do only a small range of
functions. These cells no longer divide.
2.
Meristem are active at stems and root tips,
but can become active in other parts of the
plant IF repairs to the plant are needed.
Methods of
Plant Asexual Reproduction
Cloning
1.


The process of making identical offspring
to the parent using a single cell or a small
amount of tissue from the parent.
Humans use “cuttings” or pieces of a
plant stem to place into soil and produce
many offspring identical to the parent.
2.



These plants can grow from just root
cuttings – pg 38
Growers can sell just the roots.
Eg. Dandelions, asparagus
3.



New Plants from Roots
New Plants from Stems
These plants grow from just the tips of
the runners – p 39
E.g. strawberries (runners)
Layering – A branch of the parent plant is
bent down to the ground covered with
soil.
1.



Grafting
one part of a plant is cut and connected
to a similar plant.
The result is a plant that is part one type
and part another.
used for apples, grapes and roses.
2.
Tissue Cultures
take a few unspecialized cells from a
plant

place the cells in a special growing
solution perfect for growth.

the laboratory produces many identical
plants (1 from each sample)

useful for Chrysanthemums, orchids and
pine trees.
–
(Note – specialized cells have been altered
to be able to carry out a few specialties very
well but cannot carry out other functions.)

See BLM 1-26, 28, 29,30, 31
and Do BLM 1-32 & 1-33
Grafting
YouTube - Grafting Apple Trees