Download Unit 6 ~ Learning Guide Name

BCLN BIOLOGY 11 – Rev July 2014
Unit 6 ~ Learning Guide
Name: _______________
INSTRUCTIONS
Complete the following notes and questions as you work through the related lessons.
You are required to have this package completed BEFORE you write your unit test. Do
your best and ask questions about anything that you don't understand BEFORE you
write the unit test.
6.1 NOTES: DIVERSITY OF ALGAE
General Characteristics of Algae
Most algae are traditionally considered as _____________________________ within
the 5-kingdom classification. The diagnostic characters of the algal group as a whole
were ill-defined, but nevertheless vastly different from the well-defined traits of the
other two plant subkingdoms, namely the bryophytes and vascular land plants. Other
biologists who were convinced that _______________________________________
_______________________ revised the classification, ______________________
____________________________________________, with only some multicellular
phyla, particularly the ________________________________________________
_____________________________________________, remaining as plants.
____________________________________________________________________
____________________________________________________________________
___________________________________________________________________.
The result was, and still is confusion.
All algae are ________________________________________________________.
The various types contain ________________________________________________
____________________________________________________. Most algae are
_________________________________________________________________. The
only algae that does not fall into these three classifications are those that are
unicellular in all life stages and can move on their own. ________________________
__________________________________________________________________.
While these algae reproduce by mitosis (__________________________), the green,
brown, and red algae reproduce _____________________________ similar to higher
plants. The generalized life cycle of these sexual algae is termed _________________
_______________________________________________________.
To have an _________________________________________________, an
organism ________________________________________ that are _____________
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BCLN BIOLOGY 11 – Rev July 2014
_________________________________________________. An organism can spend
equal time as each generation or it can spend most of its life as either the haploid or
diploid form.
Phylum Chlorophyta - Green Algae
Green algae possess the pigments
__________________________________
__________________________________
__________________________________
__________________________________
____________________________. Green
algae are considered closely related to
plants. All members of this phylum have a
cell wall made of cellulose and store food in
vacuoles which are characteristics of
plants. _____________________________
__________________________________
__________________________________
__________________. Green algae can be unicellular, colonial, filamentous, or
multicellular giving them a wide diversity of structure. __________________________
_____________________________________________________________________
____________________________________________________________________.
Unicellular Green Algae
Chlamydomonas is a ____________________________________________________
___________________________________________________. It usually reproduces
asexually by binary fission, but when faced with unfavorable conditions it will reproduce
sexually in a haplontic life cycle. This method of reproduction is used in unfavorable
conditions because the zygospore has a heavy protective wall. When faced with
unfavorable conditions the Chlamydomonas _________________________________
___________________________________________________________________
___________________________________________________________________
______________________________________________________________. It is
important to note that since all gametes are the same (no male or female) they are said
to have isogametes.
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Colonial, filamentous and Multicellular Green Algae
A colonial organism is __________________________
_______________________________________________.
They are not independent, but have all the capabilities of
being independent. For example, ___________is a colonial
organism composed of thousands of cells that very closely
resemble Chlamydomonas. Each cell would be capable of
independent life, but they are arranged to work in a
coordinated fashion. The Volvox resembles a sphere with a
watery inside. The wall of the sphere is made up of
Chlamydomonas-like cells. __________________________
_____________________________________________ making this one of the
simplest organisms to produce heterogametes (sperm and egg).
A filamentous organism is ______________________. The
difference is that all cells are aligned in a one cell thick strand
of filaments. An example of a filamentous algae is
___________________________, which gets its name from
the shape of the chloroplasts in the cell. Spirogyra ________
________________________________. If the strand breaks
then both strands will grow as new algae. In sexual
reproduction the contents of one strand will empty into another so there are no gametes
involved. As with Chlamydomonas, sexual reproduction produces a diploid zygote that
may be more resistant to unfavourable conditions. Spirogyra will often spend the winter
as a diploid zygote and undergo meiosis in the spring when the weather warms again
producing the haploid filament.
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These Green algae look like plants to the untrained eye.
However, there is no cellular differentiation and there is
no
protection
of
the
zygote
or
embryo.
_____________________________________________
_______________________________. The green algae
___________ so closely resembles a plant that its
common
name
is
sea
lettuce.
Ulva
______________________________________________
_____________________________. It spends equal time
as a haploid and diploid organism. Isogametes produced by the gametophyte combine
(fertilization) to form a zygote (2n) which grows to a sporophyte (2n). The sporophyte
will undergo meiosis to produce spores (n) which will grow to a gametophyte and the
cycle repeats. The adult stages, sporophyte and gametophyte, are the stages that
resemble lettuce. The leafy structure is called a thallus.
Red and Brown Algae - Phylum Rhodophyta
_______________________________________
_________________________,
but
some
species are filamentous. Most red algae are
complex, branched multicellular algae which look
like a bunch of ribbons. Red algae has an
economic importance as the main constituent in
agar. Check if it is in your favourite ice cream.
Phylum Phaeophyta
The ___________________________________
____________________________________. It
is the pigment fucoxanthin that gives this phylum
its golden brown colour. Like red algae, ______
______________________________________
_________________________. There are some
filamentous representatives as well. __________
_______________________________________
_______________________________________
______________________________________.
They often have specialized structures. At one
end you will find _________________________
______________________________________________________________________
______________________________________________________________________
Most
brown
_______________________________________________________.
algae undergo an alternation of generations life cycle, but species such as Fucus
reproduce via a diplontic life cycle meaning that the adult is the sporophyte and diploid.
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Diatoms and Dinoflagellates
Phylum Chrysophyta
Often
called
brown
algae,
_____________________________________________
_________________________________. They have a
very unique unicellular structure that reproduces
asexually. They are of economic importance as well since
their __________________________________________
______________________________________________.
Their empty shells are also mined for use in gardening
(diatomaceous earth), filters and polishes.
Phylum Pyrrophyta
Dinoflagellates are unique in that they ________________
_________________________________________________
____________. They have ___________________________
__________________________________________________
____________________________________. Dinoflagellates
are an ___________________________________________
__________________________________________. This is
of concern to humans because when consumed in large
amounts they can make the shellfish toxic enough to paralyze
whoever
eats
them.
_______________________
_____________________________________________________________________
_____________________________________________________________________
_______________________________________.
Euglenoids
Phylum Euglenophyta
Euglena are _____________________________________
for taxonomists because only a third of euglena are
photosynthetic. The rest are more like a protozoan as they are
heterotrophs and ingest their food. The typical euglena is
depicted _________________________________________
_________________________________________________
_________________________________________________.
Photosynthetic euglena can be easily found in bright aquatic
locations and are often observed live under a microscope.
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6.1 PRACTICE: DIVERSITY OF ALGAE
1. Distinguish between the terms diploid and haploid. (2 marks)
2. Alternation of Generation is an important concept in many organisms' life cycles.
Describe what alternation of generation means. (2 marks)
3. The classification scheme of algae can be quite confusing and takes
considerable practice to master. However, there are some key concepts that
even the beginning biologist should be able to master:
a. What two characteristics do all algae have in common? (2 marks)
b. Most algae classified and named based on what characteristic? (1mark)
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BCLN BIOLOGY 11 – Rev July 2014
4. Some algae reproduce asexually, some reproduce asexually and some
reproduce using both methods. Using your understanding of evolution and
thinking critically:
a. Identify and explain a selective advantage and disadvantage of
reproducing sexually. (2 marks)
b. Identify and explain a selective advantage and disadvantage of
reproducing asexually. (2 marks)
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6.2 NOTES: INTRODUCTION TO PLANTS
Interesting Facts about Plants
Bamboo is the fastest
growing plant and has
been observed to grow
over 1 meter in a 24 hr.
period
The
largest
bloom
(flower) is the stinking
lily of Southeast Asia
which measures 90 cm
across
The Welwitschia (wellWITCH-ee-a)
plant
grows in desert areas of
Namibia and Angola. It
has only two leaves that
shred into many long,
leathery pieces as they
grow.
This
plant
provides shelter for
small desert animals
and are an important
part of the web of life in
the desert.
Cinnamon is from the
bark
of
the
Cinnamomum
zeylandicum tree. The
bark is peeled from the
sprouts of these trees,
then set out to dry and
rolled up into quills
The Largest living
organism is the
California Redwood
at
111.6 m high with a 24
m circumference.
A single coffee tree
yields only one pound of
roasted, ground coffee
annually.
The squirting cucumber
(Ecballium
elaterium),
when brushed by a
passerby,
emits
its
seeds along with stream
of poisonous juice that
stings the skin.
The oldest plant is the
bristlecone pine which is
4900 years old.
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Interesting Facts about Plants Continued
•
____________________________________________________________
___________________________________________________________
•
every plant in Tomorrowland
_______________________.
•
Trees in the arctic grow very slowly.
•
____________________________________________________________
____________________________________________________________
•
The ____________________________________________________. Fires
that occur in a redwood forest take place inside the trees.
at
Disneyland
in
Anaheim,
CA
is
Kingdom Plantae
Why are plants so important? If plants hadn’t evolved to photosynthesize, life on this
planet would be very different. _________________________________________
_________________________________________________________, and the
most important waste product of this process is _________________ - something that
most of the animal life on this planet can’t live without! As the first plants began
photosynthesizing, ___ __________________________________________________
_________________________________________. Some of the oxygen in the outer
layer of the atmosphere was converted to ozone. Eventually there was enough ozone
in the upper atmosphere to effectively filter out the harmful ultraviolet rays that are
highly destructive to living organisms. This allowed organisms to survive in the surface
layers of water and on land. ___________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
________________________________. This yields much more energy than can be
obtained in an atmosphere without oxygen.
Plants are also critical to other life on this planet because ______________________
________________________________. Most plants are ______________________
_____________________________________________________________________
____________________________________________________________________.
Some of the earliest fossils found have been aged at 3.8 billion years. These fossil
deposits show evidence of photosynthesis, so plants, or the plant-like ancestors of
plants, have lived on this planet longer than most other groups of organisms.
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BCLN BIOLOGY 11 – Rev July 2014
The fossil record for plants is spottier than animals as they lack hard parts that produce
fossils but there is enough to show an evolutionary trend. _____________________
_________________ were the first to appear ______________________________
_____________________________________________________________________
____________________________________. The fossil records, DNA, and other
molecular evidence has traced the origin of plants to fresh water algae, however,
__________________________________________________ Here is a proposed
evolutionary tree for plant
General Characteristics of Plants
1.
2.
3.
4.
Plants make food by photosynthesis.
Plants have cell walls made of cellulose.
Plants stay put = Sessile.
Plants show an Alternation of Generations in their life cycles (sporophyte and
gametophyte).
Plants, like green algae, __________________________________________________
__________________________________________________________________ so
it is said that they share a common ancestor. However, plants possess many
differences in comparison to green algae, because they have to be able to survive in a
much drier environment on land.
One of the main ________________________________________________________
_____________________________________________________________________
_________________________. The cuticle is a waxy substance covering the leaves.
With this waxy cuticle present _________________________________________
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BCLN BIOLOGY 11 – Rev July 2014
________________________________________________________ in and out of
the leaves. ___________________________________________________________
____________________________________________________________________
_______________________________________________. Those plants that don't
must live in a moist environment. _______________________________________
_________________________________________ and will be discussed in more
detail later.
Plants, like algae, ______________________________________________________
__________________________________________________. There are differences
to accommodate the lack of water. For example, plants must protect the embryo from
drying out during reproduction.
Classifying Plants
The 12 Phyla of plants can be _________________________________________
___________________________ based on the presence of vascular tissue:
1. ____________________________________
2. ____________________________________
Nonvascular Plants such as Bryophyta (mosses), Hepatophyta (liver warts), and
Anthocerophyta (hornworts) __________________________________________
_________________________________________________________ (more on
plant anatomy later…).
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Vascular Plants ______________________________________________________
________________________________________________________.
•
Vascular plants can be further divided into 2 groups:
i. Seedless Plants
- _____________________________________________________
__________________________, and three other phyla closely
associated with ferns:
a. Psilotophyta (whisk Ferns)
b. Lycophyta (club Mosses)
c. Sphenophyta (Horsetails)
d. Pterophyta (Ferns)
ii.
Seed Plants
- that produce seeds for reproduction including ________________
_____________________________________________________
_____________________________________________________
-
Gymnosperm produce __________________________________
_____________________________________ (i.e., pine trees)
and include:
a. Cycadophyta (i.e. Cycads)
b. Ginkgophyta (i.e. Ginkgoes)
c. Coniferophyta (i.e. Conifers)
d. Gnetophyta (i.e. Gnetophytes)
-
Angiosperm produce __________________________________
_____________________________________ (i.e., apple and
orange trees). Angiosperms are ________________________
_________________________ and include:
a. Anthophyta (i.e. flowering plants).
 Class Monocotyledons (monocots) and
 Class Dicotyledons (dicots)
We will study each of these groups as we move through the plant module.
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Review of Photosynthesis
Photosynthesis _______________________________________________________
____________________________________________________________________
_________________. In plants, this process _________________________________
____________________________________________________________________.
Photosynthesis is the process that provides all of the energy made by producers that is
the base of the energy pyramid. Without plants and autotrophs we would have no food
to eat or oxygen to breath.
Plants absorb a common gas called carbon dioxide, pull water up through their roots
and use light to make sugar. Plants use the sugar to grow and give off oxygen as a byproduct.
The chemical reaction that takes place in chloroplasts (say inside a tree leaf) uses the
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
____________________________________________________________________.
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BCLN BIOLOGY 11 – Rev July 2014
Review of Cellular Respiration
Cellular respiration _____________________________________________________
_____________________________________________________________________
_____________________________________________________________________
__________________________________ that can do work inside cells. This process
_____________________________________________________________________
_________________________________________________. Both plants and animals
use the products of photosynthesis (glucose) for metabolic fuel.
The chemical reaction that takes place in mitochondria (say inside a muscle cell)
_________________________________________________________________
_________________________________________________________________
________________ currency of cells.
Comparing Photosynthesis to Cellular Respiration
It is important to note that ________________________________________________
____________________________________________________________________
_______________________________. The reactants and products are reversed.
They are the same reaction running in two directions.
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BCLN BIOLOGY 11 – Rev July 2014
Life Cycle of Plants
Plants use an _________________________________________________________
______________________. In the plant's cycle, the __________________________
______________________________________________________________ and the
________________________________________________________________. The
life cycles of each type of plant are dominant in one stage or the other. ____________
_____________________________________________________________________
_____________________________.
Within
the
cycle,
the
___________________________
_____ (2n) undergoes meiosis to
___________________________
_________ (n) which will typically
disperse. It will then divide and
grow
into
a
_______________________ (n).
Two gametes will combine
(fertilization) to form a zygote
(2n), which will develop into a
sporophyte (2n) to complete the
cycle.
Although the main difference
between the life cycles of
different plants is the structure that disperses the species, other differences between
the cycles will be discussed in further lessons.
6.2 PRACTICE: INTRODUCTION TO PLANTS
1. State two reasons why plants are critical to life on Earth as we know it. (2 marks)
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BCLN BIOLOGY 11 – Rev July 2014
2. Identify 4 key characteristics of plants. (4 marks)
3. Photosynthesis is key to survival of life on Earth as we know it:
a. Write the balanced equation for photosynthesis. (4 marks)
b. Identify which organelle photosynthesis occurs in. (1 mark)
c. Photosynthetic organisms that are capable of creating their own organic
molecules are known as _______________________________. (1 mark)
4. Cellular respiration is also key to survival of life on Earth as we know it:
a. Write the balanced equation for cellular respiration. (4 marks)
b. Identify which organelle cellular respiration occurs in. (1 mark)
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6.3 NOTES: NON-VASCULAR PLANTS
Types of Non-vascular Plants
________________________ plants belong
to the division ______________________,
which includes _______________________
______________________________. These
plants have ___________________________
_______________________, so the plants
____________________________________
____________________________________
________________________________. The
bryophytes __________________________
_____________________________________________________, although the plant
body is differentiated into leaflike and stemlike parts. In some species, _____________
_________________________________________________________.
With
no
vascular tissue, the bryophytes cannot retain water for long periods of time.
Consequently, ________________________________________________________
____________________________________________________________________.
This explains the presence of mosses in moist areas, such as swamps and bogs, and
on the shaded sides of trees.
______________________________________________________________________
________________________________________ generation. Therefore, they are
primarily haploid. Their only diploid stage is the zygote which grows to the sporophyte.
Both the zygote and sporophyte are parasitic on the gametophyte since they do not
have any photosynthetic tissue. The function of the sporophyte is simply to disperse the
spores so it grows above the plant to reach the wind.
•
Hornworts - Division Anthocerotaceae
Hornworts are described as a slimy looking
photosynthetic substance in the gametophyte
generation. It is the sporophyte which gives this
division its name. It grows up like a spike from the
gametophyte and continues to grow for the life of the
plant.
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BCLN BIOLOGY 11 – Rev July 2014
•
Liverworts - Division Hepatophyta
Liverworts are a _____________________________ in
the gametophyte generation _________________
________________________________. The thallus
has
____________________________________
____________________________ growing down into
the soil. Liverworts undergo both sexual and asexual
reproduction. During asexual reproduction a gemmae
will break out of the gemmae cup to form a new plant. Sexual reproduction
occurs similarly to mosses in that they have _____________
_______________________________________________________________
which fertilize to form a sporophyte. The sporophyte releases spores that will
grow to form a new liverwort.
• Mosses
_________________________
_________________________
_________________________
_________________________
________________________.
Mosses do have ______________
____________________________
____________________________
____________________________
____________________________
____________________________
___________________________.
Food molecules produced by photosynthesis within the leaf-like structures cannot be
distributed very far. As a result the mosses are generally limited in size. Mosses will
typically grow as a mat of _____________________________________.
To summarize:
1. __________________________________________________________
2. __________________________________________________________
__________________________________________________________
3. __________________________________________________________
4. Mosses are small due to their lack of vascular tissue.
5. They depend on diffusion and osmosis for the movement of materials
throughout the plant.
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BCLN BIOLOGY 11 – Rev July 2014
Life Cycle of the Mosses
The life cycle of the moss is typical of the bryophytes. Flask-shaped
_____________________, located among the top leaves of the __________________
______________________________________________________________, located
similarly on the ________________________________________________________
__________________________________ that swim in drops of rainwater or dew into
the neck of the archegonium to fertilize the egg cell.
The zygote that results from the fertilization develops into a young sporophyte within
the archegonium. The sporophyte grows out of the archegonium, taking its
nourishment from the gametophyte, and differentiates into a slender stalk with a spore
capsule near the tip. Haploid spores are produced by meiosis in this capsule, and
when the tip of the capsule opens, the spores are freed. _______________________
_______________________________________________________________, which
represent the next stage in the alternation of generations.
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BCLN BIOLOGY 11 – Rev July 2014
Review
____________________________________________________________________
____________________________________________________________________
______________________________and is the form we recognize as ‘mosses.’ At the
tip of the gametophyte are reproductive structures called the ____________________
___________________________________________________________________.
When sperm swims to the egg fertilization produces a zygote. When the zygote
germinates it produces a diploid sporophyte. The sporophyte is totally dependent on
the gametophyte for food and water as it grows on top of the gametophyte. The
sporophyte has a capsule on top that contains haploid spores (produced by meiosis).
Once a spore is released and it lands, it germinates into a mass of green filaments
called a Protanema. This protanema develops shoots and rhizoids and becomes the
dominant haploid gametophyte.
Evolutionary Importance
Nonvascular plants are important to evolutionary biologists because they __________
____________________________________. They have some tissue differentiation
but are obviously not as advanced as vascular plants. They are dependent on a nearly
aquatic lifestyle for part of their life cycle. They are considered the most primitive of the
plant kingdom and they are also known as great __________________
__________________. Bryophytes are also important ________________________
____________________________________________________________________
_________________________________________.
.
6.3 PRACTICE: NON-VASCULAR PLANTS
1. Identify 3 key differences between non-vascular plants and algae. (3 marks)
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BCLN BIOLOGY 11 – Rev July 2014
2. Define and explain the functions of the antheridia and archegonia. (4 marks)
6.4 NOTES: SEEDLESS PLANTS
Types of Seedless Vascular Plants
Vascular plants are divided into two main groups, seedless and seed. While _________
______________________________________________________________________
____________________________________________. The seedless divisions include
______________________________________________________________________
____________________________.
The structure of the vascular tissue is common to all vascular plants. _______________
______________________________________________________________________
_______________________________________________. It is the xylem that enables
vascular plants to be tall. Not only is the xylem capable of transporting water to the
leaves of tall plants but the xylem is also responsible for stability in woody tissues.
These tissues help the plant fight gravity and the wind.
______________________________________________________________________
________________________________________ generation. It is beneficial to be
diploid because a faulty gene can be masked by its duplicate if it is normal reducing the
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BCLN BIOLOGY 11 – Rev July 2014
chance of mutation. _____________________________________________________
__________________________________________________ if a genetic change does
occur.
______________________________________________________________________
______________________________________. However, they ___________________
______________________________________________________________________
_________________________________. They can live in dry environments in the
sporophyte generation because the gametophyte is independent.
•
Whisk Ferns - Division Psilophyta
Whisk ferns are an interesting group of plants because they
have no leaves. Instead, the branches of the plant carry on
photosynthesis and hold the sporangia which produce the
spores.
•
Club Mosses - Division Lycopodophyta
Club mosses are composed of a ______________________
____________________________________ with small roots
branching from it. They look like a more complexly branched
whiskfern, but they actually have leaves. The small scale-like
leaves branch off of the stem. The sporangia are held by
specialized leaf clusters called strobili.
•
Horse Tails - Division Equisetophyta
This division is made up of only 15 species, all of which are in
the same genus. However, they are still found worldwide in
moist habitats. Horsetails have a single stem growing up from a
rhizome and whorled (circular arrangement) branches off of the
stem. The horsetails also have a specialized leaf arrangement
for holding the sporangia. It is called a strobilus because there is
only one.
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BCLN BIOLOGY 11 – Rev July 2014
•
Ferns - Division Pteridophyta
Most
ferns
________________________________________
________________________________________. They range from less than
1cm to 25 m tall. Ferns live in all climates, on forest floors, as epiphytes (survive
by living off of other plants), in full sun. Some ferns are aquatic.
The ____________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________.
The stems contain specialized vascular tissues for transporting water and
dissolved substances from one part of the plant to another. Strong stems
containing this vascular tissue allow plants to grow tall.
Fern Life Cycle
Like other seedless vascular plants, _________________________________
________________________________________. However, ferns vary in
size and shape much more than the other divisions. Typically, the
____________________________________________________________
____________________________________________________________
_________________________________. After the sperm swim to the
____________________________________ they fertilize the egg forming a
zygote. The ___________________________________________________
____________________________ that is a small curled stem with leaves.
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
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Diagram of Fern Life cycle
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BCLN BIOLOGY 11 – Rev July 2014
6.4 PRACTICE: SEEDLESS PLANTS
1. Define vascular tissue with respect to plants. (1 mark)
2. Explain how vascular tissue enables a plant to grow larger. (2 marks)
3. Some plants are non-vascular while others are vascular. Using your understanding
of evolution and thinking critically:
a. Identify and explain a selective advantage and disadvantage of being nonvascular. (2 marks)
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BCLN BIOLOGY 11 – Rev July 2014
b. Identify and explain a selective advantage and disadvantage of being
vascular. (2 marks)
~ END OF BIOLOGY 11 UNIT 6 LEARNING GUIDE ~
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BCLN BIOLOGY 11 – Rev July 2014
UNIT 6 ANSWER KEY
6.1 PRACTICE: DIVERSITY OF ALGAE
1. Distinguish between the terms diploid and haploid. (2 marks)
-
diploid cells = 2n meaning they have two identical (barring mutation) copies of each
chromosome
-
haploid cells = n meaning they have one copy of each chromosome
2. Alternation of Generation is an important concept in many organisms' life cycles. Describe what
alternation of generation means. (2 marks)
An organism that has an alternation of generation life cycle will alternate between a
haploid stage and a diploid stage, although the length of time the organism spends in
each stage can vary greatly depending on the species. In plants the sporophyte is
diploid (2n) while the gametophyte is haploid (n).
3. The classification scheme of algae can be quite confusing and takes considerable practice to
master. However, there are some key concepts that even the beginning biologist should be able
to master:
a. What two characteristics do all algae have in common? (2 marks)
-
aquatic and photosynthetic
b. Most algae classified and named based on what characteristic? (1mark)
-
the type of pigments they contain
4. Some algae reproduce asexually, some reproduce asexually and some reproduce using both
methods. Using your understanding of evolution and thinking critically:
a. Identify and explain a selective advantage and disadvantage of reproducing sexually. (2
marks)
-
advantage = greater genetic diversity = greater chance of surviving natural
selection as a species
-
disadvantage = must find a "partner" to reproduce with
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BCLN BIOLOGY 11 – Rev July 2014
b. Identify and explain a selective advantage and disadvantage of reproducing asexually. (2
marks)
-
advantage = rapids, no partner necessary so can occur anywhere, anytime
-
disadvantage = generally less genetic diversity = less chance of surviving
natural selection as a species
6.2 PRACTICE: INTRODUCTION TO PLANTS
1. State two reasons why plants are critical to life on Earth as we know it. (2 marks)
-
animals are obligate aerobes meaning they require oxygen to live, without
photosynthetic organisms like plants the Earth would lack oxygen and therefore
animal life as we know it
-
plants are producers (autotrophs) that can convert water, carbon dioxide and solar
energy into carbohydrates that are used to support all of Earth's consumers
(heterotrophs) including humans
2. Identify 4 key characteristics of plants. (4 marks)
-
Photosynthesis…ability to produce own food from water, carbon dioxide and solar
energy
Cell walls that contain cellulose – affording structure and protection
Sessile – do not move throughout their life cycle
Alternation of Generations – switch between diploid sporophyte and haploid
gametophyte throughout their life cycle
3. Photosynthesis is key to survival of life on Earth as we know it:
a. Write the balanced equation for photosynthesis. (4 marks)
6 H 2 O + 6 CO 2 + Solar Energy  C 6 H 12 O 6 + 6 O 2
b. Identify which organelle photosynthesis occurs in. (1 mark)
-
chloroplasts
c. Photosynthetic organisms that are capable of creating their own organic molecules are
known as _______________________________. (1 mark)
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BCLN BIOLOGY 11 – Rev July 2014
4. Cellular respiration is also key to survival of life on Earth as we know it:
a. Write the balanced equation for cellular respiration. (4 marks)
C 6 H 12 O 6 + 6 O 2  6 H 2 O + 6 CO 2 + Energy (in form of ATP)
b. Identify which organelle cellular respiration occurs in. (1 mark)
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mitochondria
6.3 PRACTICE: NON-VASCULAR PLANTS
1. Identify 3 key differences between non-vascular plants and algae. (3 marks)
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cuticle = waxy outer layer to protect plant from drying out
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stomata = pores for gas exchange
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adaptations to prevent embryos from drying out
2. Define and explain the functions of the antheridia and archegonia. (4 marks)
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Archegonia are found in the female gametophyte and produce eggs
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Antheridia are found in the male gametophyte and produce sperm
6.4 PRACTICE: SEEDLESS PLANTS
1. Define vascular tissue with respect to plants. (1 mark)
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Vascular tissue refers to vessel systems used to move substances throughout the
plants. There are two main types of tissues namely xylem and phloem.
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Xylem = transports water and minerals from roots, upwards throughout the plant
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Phloem = transports nutrients produced in the leaves by photosynthesis to all other
parts of the plant
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BCLN BIOLOGY 11 – Rev July 2014
2. Explain how vascular tissue enables a plant to grow larger. (2 marks)
Vascular tissue enables a plant to grow larger as water, minerals and nutrients can be
delivered over a greater area/volume than in non-vascular plants. Most material can
diffuse effectively through tissues about 1 – 2mm thick (such as found in non-vascular
plants) but once tissues exceed this thickness (such as in vascular plants) they must be
supported by vascular tissue to ensure all the cells receive the resources necessary for
survival.
3. Some plants are non-vascular while others are vascular. Using your understanding of evolution and
thinking critically:
a. Identify and explain a selective advantage and disadvantage of being non-vascular. (2
marks)
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advantage = less complex = potentially more efficient
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disadvantage = must have regular, easy access to water such as in swamps
and bogs
b. Identify and explain a selective advantage and disadvantage of being vascular. (2 marks)
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advantage = ability to survive in more diverse environments (with limited
water)
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disadvantage = more complex, potentially less efficient
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