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
Cell need to divide for the following
reasons:
Normal Cell Replacement
1.
a)
Cells die of old age and need to be
replaced. See pg 25 for cell life spans.
•
b)
c)
About 3 billion cells die in your body every
minute.
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)
As organisms grow larger, their cells
stay the same size
b)
They just get more of them.
Aging
1.
2.
Aging is connected to the slowing of the
cell cycle.
The cells do not divide as often or as
quickly.
Cancer
1. Caused when the DNA of a cell becomes
damaged by:
a) Tobacco
b) Asbestos
c) Certain chemicals
d) some viruses
e) Radioactivity
f) 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.
2.
3.
4.
5.
6.
•
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.
 Eat
What are four primary habits that
everyone should adopt to lower their
overall cancer risk?
Healthy
 Be Active
 Get Screened
 Don’t smoke
Eat Healthy
 1/3
of cancer deaths are linked to diet
 Reduce dietary fat, especially animal fat
 Start small – add a few servings of fruits or
veggies/day
 Limit alcohol consumption (men-2,
women-1)
 Eat less red meat & cut out processed
meats
Be Active
 Make
physical activity part of daily routine
 Make it part of your social life
 Schedule activity for your “energy’ times
 Stay motivated – checklist or friend
 Learn new skills – club, group etc.
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 (text p 29-35)
Reproduction – the formation of
a new individual that has identical genetic
information to its parent.
 Asexual
Reproduction
Sexual
Asexual
Binary Fission
Budding
Conjugation
Spore Formation
Fragmentation
Hermaphroditic
Vegetative
Reproduction
Separate Sexes
Bacteria – see p 29-30
1. Have no nuclear
membrane
(prokaryotic)
2. Have only one
chromosome
3. Reproduction
asexually by the
process of binary
fission.
http://www.microscopesblog.com/2010_09_01_archive.htm
l
http://www.frankswebspace.org.uk/ScienceAndMaths/biology/pathoge
nsBacteria.htm
Binary Fission
4. Steps (see p 30)
a) cell wall ruptures
b) single chromosome
gets copied
c) cell grows longer
and a chromosome
moves to each end.
d) cell membrane
pinches off.
e) cell wall grows to
surround both cells.
http://www.biologycorner.com/APbiology/pathology/bacteria.html
Protists
1. Ex) paramecium,
amoeba, euglena,
vorticella
2. unicellular organisms
with a true nucleus
(eukaryotic).
3. mitosis takes place
creating two identical
cells.
http://www.psmicrographs.co.uk/paramecium-sp--protozoa/scienceimage/80016644
Fungi
1. Ex) Moulds, yeast,
and mushrooms
2. filaments called hyphae
grow over the surface of
food.
http://www.digital-photography-school.com/how-tophotograph-mushrooms-toadstools-and-fungi
http://leavingbio.net/FUNGUS/Fungi2.htm
http://www.phyterra.com/technology/about_yea
st.html
http://www.factmonster.com/dk/encyclopedia/fungi.html
3. Have 3 methods of asexual
reproduction
a) Fragmentation
– a small piece of
hyphae breaks away
and grows into a new
individual. It is
identical to its parent.
(fungi – p 32)
Athletes Foot Fungi
http://www.biologyjunction.com/fungi_notes_b1.htm
b) Budding
- a copy of the
nucleus is made.
- The nuclei press
against the cell
membrane, forming
a bud which grows
and breaks off.
(hydra & yeast)
•
http://coralreefmultimedia.org/reef/s
horts.pop?topic=Reproduction#
http://rushartsbiology.wikispaces.com/Visuals+-+Unit+5
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)
http://leavingbio.net/FUNGUS/Fungi2.htm
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 on
p 19 in notes pack.
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. Animals stop growing at an adult size
2. Plants grow until they die.
3. Meristem – unspecialized cells in the
stem and root tips which undergo
mitosis very often.
4. Meristem cells divide and promote
growth at the stem and root tips.
Meristem (cont’d)
5. At some point some meristem cells
specialize to do only a small range of
functions. These cells no longer
divide.
6. 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


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.
1. New Plants from Roots



These plants can grow from just root
cuttings – pg 38
Growers can sell just the roots.
Eg. Dandelions, asparagus
2. New Plants from Stems

These plants grow from just the tips of
the runners – p 39 & BLM 1-29


E.g. strawberries (runners)
Layering – A branch of the parent plant is
bent and covered with soil – BLM 1-30
3. 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.
This method is used for apples, grapes
and roses.
4. 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)
Text p 40
4. Tissue Cultures (cont’d)


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