Unit A Study Guide: Science 9
Unit A: Biological Diversity
STS and Knowledge:
- Investigate and interpret diversity among species and within species, and describe how diversity contributes to species survival.
SIA pp. 9 /
So, what is biodiversity?
- Biodiversity refers to the number and diversity (variety) of living organisms in a community.
- A large biodiversity assures the health and survival of natural communities because of the many interactions possible between species.
- Environmental change is better supported when there is a large biodiversity
- Ex: a disease may kill members of a certain species but leave others untouched (i.e. Pine Beetles in BanffNational Park)
- We measure biodiversity by comparing the number of species to the total population (the INDEX of diversity)
1. Biological diversity consists of a variety of ecosystems and species on Earth and the ecological processes they are part of. There are three main components to biological diversity. All three are important for Alberta’s ecosystems.
The first component refers to diversity in all living and non-living things on Earth. The second component refers to the populations of species that live in certain communities. The third component refers to the diversity found at the cellular level.
What is the correct order for the biological diversity components referred to in the article?
a) community, ecosystem, and genetic
b) community, genetic, and ecosystem
c) ecosystem, community and genetic
d) genetic, ecosystem, and community
SF pp. 8
SIA pp. 9 / observe variation in living things, and describe examples of variation among species and within species (e.g., observe and describe characteristics that distinguish two closely related species)
Species: A group of organisms that are similar in appearance and that can reproduce offspring with the same general characteristics that can be passed on to future generations of viable offspring.
Example: A horse and a donkey are species. The mule, which is a hybrid of the two species cannot reproduce viable offspring, therefore the mule is not considered a species.
Variation is differences within a group of similar living things. Therefore, no two organisms even within the same group are alike. Variation allows for greater chances of the survival of a population when faces with change.
Examples: Facial characteristics or hair colour of people. (Note that this is within the same group of a breeding population).
2. Which of the following is an example of variation within a species?
a) Darwin studied a variety of finches in the Galapagos islands that had different styles of beaks.
b) Different students in a classroom have blue, brown, or green eyes.
c) A forest consists of pine, spruce and poplar trees.
d) Black bears and Grizzly bears share a meadow.
SF pp. 16
SIA pp. 18 / identify examples of niches, and describe the role of variation in enabling closely related living things to survive in the same ecosystem (e.g., investigate different bird species found in local park ecosystem, and infer how each is adapted to life within that ecosystem)
Ecosystem: any place in which living (biotic) things live and interact with other biotic and abiotic (non-living) things
Ecosystem Diversity: the different types of communities and environments (i.e. bogs, marshes, lakes, forests) in which biotic and abiotic things can be found
Population: members of a same species living in a specific area and sharing resources
Community: populations of different species living in the same area
Niche: A niche is the organism’s job or role in the environment or ecosystem.
Example: A hawk’s role is a predator in the environment. A fungus’ role is the breakdown of decaying matter in the environment.
Two types of niches:
- Broad: Certain regions permit the establishment of very large populations, but do not support a wide variety of species
- In northern Canada, there are limited numbers of different species (little variety). However, there is a very large caribou population.
- Organisms are generalists – they must be able to adapt to a wide variety of environmental conditions to survive (i.e. eat a wide variety of plants, adapt to temperature and season change)
- Narrow: Certain organisms have very specific ecological niches that permit them to live in close proximity with other organisms.
- Organisms are specialists since they are very effective at surviving in their surroundings. They are so well adapted to living in their environment that they could NOT survive in another. Thus, they cannot propagate and populate large areas. It’s the ‘trap of specialization’!
- Examples: The macaque monkey is specialized for life in the forest canopy – as tress are cut down it has nowhere to live!
SF pp. 8-10
SIA pp. 9,10,20,21 / The role of variation: Variation allows similar organisms to survive external threats. This allows many species that may have the same niche or job to thrive even if one of the species is eliminated from the same habitat.
Example: Different trees are producers in a boreal forest. If a disease which affects only pine trees, wipes out the entire pine tree population, the other trees can still continue their niche.
Adaptation: species adjust to the surrounding conditions
- Morphological: Physical Change.
- Behavioural: Change in behaviour (i.e. migration, night hunting…)
3. An organism’s niche can be described by:
a) how an organism can change to adapt to its surroundings
b) where an organism lives and what it does
c) what type of food an organism eats
d) what kind of predators an organism has / 4. Which of the following statements is correct?
a) A community refers to the same species living in an area.
b) A community consists of non-living things in the same area.
c) A population refers to all living things in an area.
d) A population consists of members of the same species.
5. Which statement best describes the niche of a wolf in Alberta?
a) The wolf, found throughout the boreal forests and mountains of Alberta, is a predator feeding on herbivores.
b) The wolf, found in the mountains of Alberta, is a consumer.
c) The wolf is a predator feeding on deer and moose.
d) The wolf lives exclusively in BanffNational Park in Alberta.
SF pp. 21
SIA pp. 27-29 / Investigate and interpret dependencies that link the survival of one species to the survival of others. (Eg: by providing habitat, food, means of fertilization or a source of oxygen)
Dependency: Organisms in any given environment depend on one another for their basic needs. These relationships can include symbiosis, predation, general or specific types of relationships.
Example: Flowers need bees to pollinate and the bees need the nectar from the flowers.
SF pp. N\A
SIA pp.17 / General relationships are where trees take in carbon dioxide and release oxygen and most other organisms need oxygen and produce carbon dioxide.
Specific relationships involve the interaction of two groups and symbiosis and predation are two examples.
Symbiosis is a close relationship between two different organisms over time. It can be mutual where both organisms benefit. It can be commensal where one benefits and the other is unaffected, and it can be parasitic where one benefits at the cost of the other.
Predation is where one organism kills another.
Interspecies Competition: a type of relationship between organisms where neither one benefits. It happens when 2 or more species need the same resources.
Example: Two species compete for the same food. Thus, there is less food for each of the species.
6. A deer in the Y2Y area was infested with ticks. What type of relationship does this best describe?
a) mutualism
b) commensalism
c) parasitism
d) competition
7. What type of interdependence between species is represented in this graph?
a) symbiosis
b) predator-prey
c) commensalisms
d) mutualism
SF pp. 17
SIA pp. 28,29 / Identify the role of variation in species survival under changing environmental conditions.
Variation in species: Variation in species allows for the survival of a species because the differences within the characteristics allows each to deal with external threats differently.
Examples:
1. A bacterial population which is exposed to an antibiotic will be killed. However, there will be some bacteria which can tolerate the antibiotic due to variation.
2. The peppered moth has a variety of colouring from very dark to very light. During the industrial revolution in England, their environmental conditions changed because the factories emitted smoke and the soot covered the trees. The light moths were eaten because they no longer could adapt to their dark environment. The peppered moth species continued because the dark ones survived the environmental change.
2. Investigate the nature of reproductive processes and their role in transmitting species characteristics.
SF pp. 26-28, 30
SIA pp. 30,31 / Distinguish between sexual and asexual reproduction and identify and interpret examples of asexual and sexual reproduction in different species, by ;
Sexual Reproduction involves the union of male and female sex cells and requires two parents. Offspring are different because they have characteristics of both parents.
Asexual reproduction does not involve the union of male and female sex cells but is actually the transmission of the same genetic information from a parent to its offspring. Basically the offspring is an exact copy of the parent.
Describing types of asexual reproduction
Binary Fission: Asexual reproduction found in single cell organisms where the genetic information is copied and the cell divided into two identical cells equal in size.
Example: bacteria and amoeba cells
Budding: The formation of a bud on an organism which grows to become a new organism independent of the parent. Its DNA is identical.
Example: A hydra specimen.
Spore Production: Production of a hardcoat seed-like structure, but are produced by the division of cells of one parent and not the union of two sex cells.
Example: A fern plant produces spores in one part of its life cycle and then produces sex cells (zygospores) in the other part of its life cycle.
Vegetative Reproduction: Involves only plants where a new plant can be formed from the vegetative parts of the parent. Example: Runners in strawberries, the eyes on the potatoes, cuttings of colius plants, the bulbs of daffodils and tulips, and suckers from aspen trees.
8. You observe vegetative reproduction as a method of asexual reproduction. What are three other forms of asexual reproduction?
a) spore production, pollination, budding
b) pollination, fertilization, budding
c) spore production, budding, binary fission
d) budding, fertilization, spore production
9. It is observed that many maple trees in an area are developing shoots or suckers. What form of reproduction does this represent?
a) spore
b) budding
c) vegetative
d) binary fission / 10. Which of the following organisms is most likely to reproduce asexually?
a) salmon
b) frogs
c) mushrooms
d) kangaroos
SF pp. 30-35
SIA pp. 32-33 / Describing representative types of sexual reproduction
Bacterial Conjugation: This is the primitive type of sexual reproduction. One bacterium grows a tube-like structure and passes on a copy of its DNA to another bacterium.
Example: bacteria
Plant and animal reproduction: This involves two parents whose sex cells undergo a process called meiosis where the DNA of each parent is divided in half and transmitted to the offspring. The offspring receive half of the genetic information from each parent.
Example: Humans have 46 chromosomes and a person gets 23 chromosomes from their mother and 23 chromosomes from their father.
SIA pp. 35 / Describing examples of organisms that show both sexual and asexual
Reproduction
Plants: Plants can reproduce by making seeds. Seeds are made by the union of sperm cells within a pollen grain and an egg cell produced by the ovary of the female plant structure. Plants can also reproduce by cuttings, suckers, runners, and bulbs. Example: asparagus, potatoes, spider plant
Yeast can reproduce by both budding and sexual reproduction.
11. On a field trip to a provincial park, a naturalist shows you several things.
- When a starfish loses its arm, it can grow it back and the lost arm has the ability to grow a new starfish.
- Salmon return every four years to spawn in the stream where they hatched.
- Sea Anemones live in colonies along the shore;some colonies consist of over 100 identical sea anemones. This means they are all clones.
- Sponges and sea slugs can reproduce sexually and asexually.
a) starfish and seas anemones
b) sponges and starfish
c) sea slugs and sea anemones
d) salmon and sponges
SF pp. 30-35
SIA pp. 32-33
SF pp. 33
SIA pp. 33 / Describing the formation of zygote and embryo in plant and animal reproduction
Sexual reproduction in plants and animals involves the joining of male and female sex cells called gametes.
Plants:
Angiosperm: flowering plant
Gymnosperm: plant that produces seeds inside of cones
Self-pollination: the sperm and the egg (the two gametes) come from the same plant
Cross-pollination: gametes come from two different plants
Plants usually produce both male and female gametes although some species produce only male or only female. The flowers are the reproductive structures of the plant. The pollen is a hard structure that contains the male gametes. The pollen is found on the male reproductive structure called the stamen. Pollen is made in the anther of the stamen. Animals, wind, and water can transfer the pollen to the female reproductive structure called the pistil. Sperm that are in the pollen travel to the egg via a tube cell in the ovary of the pistil and fuse together to form a zygote. A zygote is the first stages of a new developing plant. The two seed leaves called cotyledons which feed the plant while it grows plus the embryo surrounded by a hard coat is called a seed. A plant embryo is a young developing multicelled organism which contains a miniature leaf (epicotyl), root (radical) and stem (hypocotyl).
12. Match the number in the diagram to the correct label below.
______
pistil anther ovary stamen
SF pp. 35
SIA pp. 32 / Animals: In animals, males and females make sex cells called gametes that must arrive at the same time to fuse together in a process called fertilization. A liquid environment is necessary for the sex cells because they are delicate and can dry out easily. In frogs where sexual reproduction is external, the reproduction takes place in the water and the sperm swim to the eggs in the water. In human, the male body produces semen which contains sperm. In animals such as sponges, frogs, amphibians, reproduction is external (occurs outside the body). In animals like insects, mammals, birds, and reptiles, fertilization occurs internally.
Internal fertilization has a high rate of success because it protects the embryo from the climate and from predators
External fertilizationposes extreme risk because gametes could be eaten by predators or washed away by the currant. They can also be subjected to extreme temperature, come in contact with pollutants or be deprived of oxygen. The majority of gametes are lost or destroyed.
When sperm and egg meet, they form a zygote.
As the zygote develops after many cell divisions, it is called the embryo. In animals, an embryo is a multi-cellular organism during early development.
**How many chromosomes are there in a zygote? In an embryo?
13. During sexual reproduction, the sperm unites with the egg in the process of fertilization. What is created by the joining of these two cells?
a) a gamete
b) a zygote
c) an embryo
d) a bud
SF pp. 37,38
SIA pp. 28 / Describe examples of variation of characteristics within a species, and identify examples of both, discreet and continuous variation.
Discreet variation refers to a trait that has only a few physical expressions. This means that there is limited ways of showing this trait.
Example: Crossing your arms or clasping your hands. Which arm is on top, which thumb is on top? When crossing your arms, the right hand up is dominant in our current human population and left hand up is recessive. When clasping your hands, the right thumb over the top is dominant in our current human population and the left thumb over the top is recessive.
Continuous variation refers to a trait that has a range of expressions.
Example: There is a range of hair colour or eye colour, height, etc.
14. Which of the following is an example of discrete variation in genetics?
a) weight
b) skin color
c) height
d) blood type / 15. Prairie dogs captured in a proposed study area were all different in size and in mass. Which term best describes this range of characteristics?
a) heritable characteristic
b) discrete variation
c) non-heritable characteristic
d) continuous variation
SF pp. Pg.37
SIA pp. 39
SF pp. 30-35
SIA pp. 32-33
SF pp. 41
SIA pp. 53
SF pp. 41
SIA pp. 53 / Investigate the transmission of characteristics from parents to offspring, and
identify examples of characteristics in offspring that are :
the same as the characteristics as the parents
Racial features such as single or double folded eyelids (asian-white),
the same as the characteristic of one parent
As one of your parents, you will be either male or female.
intermediate between parent characteristics
Eye colour, height, weight, hand span, feet size.
different from both parents
Red and white snap dragons can produce a pink snap dragon. The offspring gets chromosomes from each parent that enable it to produce both white and red pigments. The expression of one is not dominant over the other therefore an intermediate colour is produced. This pattern is called intermediate or incomplete dominance.
16. Purebred white snapdragons and purebred red snapdragons were planted in flowerbeds at the zoo. The following year, pink snapdragons appeared. What pattern of inheritance explains this colour change?
a. incomplete dominance
b. recessiveness
c. dominance
d. co-dominance
SF pp. 42
SIA pp. 32-33 / Distinguish those characteristics that are heritable from those that are not heritable and identify characteristics for which heredity and environment may both play a role.