mr. nielsen
DESCRIPTION
Mr. Nielsen. [email protected] 929 6282 This covers up to mitosis and meiosis in topic 5. Your personal imail account. http://imail.blackgold.ab.ca/ Use the password I give you and don’t forget it. Useful Websites. www.blackgold.ab.ca/ict - PowerPoint PPT PresentationTRANSCRIPT
Your personal imail account
• http://imail.blackgold.ab.ca/• Use the password I give you and don’t
forget it
2
3
Useful Websites• www.blackgold.ab.ca/i
ct• Any website that I
reference in class or provide a link for could be useful
• ALL powerpoints are in the student pick up folder and ready for you to download
4
Things you need to do EVERYDAY
• Bring a notebook and textbook• Pens and pencils• Calculator• USB stick• As soon as the bell goes you are ready to
start class
5
Note Taking• I will help you to take better notes by • Paraphrasing • Abbreviating • Creating your own symbols and characters• Just actively listen! Not everything needs to be
written down.• All powerpoints can be taken home anyway• Be careful that you take the time to study
everyday (it only takes a few minutes)
6
• http://www.biology.ualberta.ca/courses/?Page=337
7
Ecosystem, Species, and Genetic Diversity
• Biologists have identified – over 1.5 million species of animals– more than 350,000 species of plants– there are more insect species than both animals
and plants combined• Biologists estimate there are 30 - 100
million kinds of organisms
8
• 3 main components of biological diversity– ecosystem diversity– community and species diversity– genetic diversity
• Ecosystem– any place on Earth where living (biotic) things interact
with other living and non-living (abiotic) things• Ecosystem Diversity
– different types of living communities and environments such as bogs, marshes, lakes, and forests
9
• Population– A number of the same species in the same area using
the same resources, counted at a specific time– Examples?
• Community– is when populations of different species live in the
same area and interact– Examples?
• Species Diversity– occurs within individual organisms of the same
species, also called variation
10
• Diversity can occur at the Population, Community, Species and Genetic level
11
• Genetic Diversity (cont.)
– genetic information is like the language to build the body• very few letters but very long words
– we know all the letters but we are not yet able to understand the whole thing
– Genetic information represents the potential for adaptation to long-term natural and human-caused changes in the environment
12
– If a populations lacks genetic information or genetic diversity, then it might not be able to survive environmental change and reproduce• e.g. Cheetahs - there are so few Cheetahs
now that there genetic information is so narrow that many Cheetahs that are still-born
• Some wolf populations are experiencing the same effect
13
14
Types of Variation
• Variation between different species:– Some species fly where others walk , climb or
swim
15
Variation for survival • Structural adaptations – physiological traits that
add to an organisms survival• Behavioral adaptations – character trait that adds
to an organisms survival• Behavioral Adaptations
– nocturnal predators– Some birds pretend to be wounded to keep young safe– Burrowers
• See page 12
16
Structural Adaptations
• Pitcher plant is structurally adapted to survive in nitrogen poor soil by trapping and digesting insects
17
Behavioral Adaptations
Vampire Bats are nocturnal- they choose to be active at night which helps hide them from prey
18
• Species distribution– species on this planet are not distributed evenly– the greatest number of plant species can be
found around the equator.• Why do you think this is?
–The greatest biodiversity is found in the tropical rain forests in equatorial regions
– the least amount of biodiversity is found in the Arctic and Antarctic regions (polar regions)
19
• Classifying Biological Diversity– A naming system was designed in the 18th century by
Carlos Linnaeus– This naming system uses Latin– Linnaeus’ system uses two words to name each living
thing• the first word indicates the name of the genus to which the
organism belongs• the second word indicates the particular species
– no two species can have the same name– Closely related species can have the same genus name, but not the
same species name» e.g. Pogona vitticeps (inland bearded dragon) and Pogona
henrylawsoni (Lawson’s dragon - miniature bearded dragons)
20
• Five-kingdom classification system– Animalia
• animals– Plantae
• plants– Fungi
• yeasts, moulds, and mushrooms– Protista
• mostly singled-celled organisms– Monera
• bacteria
21
– Kingdoms • are divided into a series of phyla (the plural form of phylum) • and also, but not always, subphyla
– Phyla• are divided up into classes
– Classes• are subdivided into orders
– Orders• are divided into families
– Families• are divided into genera
– Genera• is finally divided up into species
22
• Variation within a species–variation within a species is called variability–variability of a species is very important if the
environment where that species lives changes• environmental changes don’t always mean
weather/climatic changes • the introduction of a new predator, the spread of a
new disease, the introduction of a toxic substance, or the elimination of a food source are all good examples of environmental changes.
– if a species has great deal of variation among its population its more likely to survive the change
23
24
Types of Variation
• Variation can also be seen within a species– Slight differences in size, fur or hair colour– Polymorphism (many types) – bees, termites
and ants have drones, workers, soldiers and a queen
– Sexual Dimorphism – males and females of the same species look very different, often seen in birds
25
26
27
28
29
• Variation within a species (cont.)
– remember the Cheetahs example• their numbers are so low (i.e their genetic variability is low)
that they can’t cope with any environmental changes– i.e new diseases, elimination of a food source, etc.
– how variability helps in survival can be seen in the growing problem of certain bacteria becoming more resistant to antibiotics
– penicillin (one of the first antibiotics) used to be very effective against some forms of bacteria. Today that effectiveness is becoming much less. Scientists think that the over-prescription of antibiotics has allowed a few resistant bacteria within populations with variability to survive. If this continues the resistant bacteria population will replace the current populations and antibiotics will not be effective.to avoid this, antibiotics should only be given when absolutely necessary.
30
– One example where species variability has helped a species is the Galapagos Finches
• It is believed that a small population of finches was located to these group of islands
• because of the variability this population was able to survive and adapt to each of the specific islands
• There are now 13 different type of finches on these Galapagos islands which is believed to have evolved from 1 species of finch
31
Activity
• Page 11 – Galapagos Finches• How do we measure biological diversity?
– Biological Index– Compares the diversity of species in an area
with the total number of organisms in the same area (see page 13)
32
33
Measuring Biological Diversity• A diversity index calculation can be used to compare the
diversity of species in an area with the total number of organisms in the same area.
• Diversity Index = __Number of Runs___ • Number of Specimens•• Where : runs = change from one species to another
along the study area • specimens = total # of
specimens in the area (total # of letters)• The larger the diversity index the greater the biodiversity
in the area.• Example: see text p. 14
34
Measure the biological diversity
35
Measure the biological diversity
36
Questions
• Page 15• Answer all questions on your own and we
will take them up next class
37
Topic 2 – Habitat and Lifestyle
38
Interdependence• No species can survive by itself
– each species is dependent on many other species in its environment
• one type of interdependence is called symbiosis– sym meaning together– bios meaning life
• There are several different types of symbiosis– These types are determined by whether the organisms
benefit from or are harmed by the relationship
39
• the first type is commensalism– one of the organisms benefits but the other does not
• however the second organism is not hurt or harmed by this symbiosis (+. 0)
– An example of commensalism is• exist between remoras (or sharksuckers) and larger marine
fishes, especially sharks and rays.– The dorsal fin of the remora is specially modified to form a sucking
apparatus that is used for attachment to the host. The remora benefits by saving energy due to its limited swimming and obtains food scraps when its host is feeding.
40
• Another type of symbiosis is Mutualism (+,+)– here both organisms benefit from this interdependence– an example of mutualism is
• exists between Rhinos and oxpeckers (also known as Tick birds)
• The birds eat ticks they find on the rhinos and noisily warns of danger
41
• Another type of symbiosis is Parasitism (+, -)– One organism benefits and the other is harmed– tapeworm
• there is one type of interaction that neither species benefits. This is called interspecies competition (-,-) or (-,0).– Interspecies competition happens when two or more
species need the same resource.
42
• interspecies competition (cont.)
– limits the size of the populations of the competing species by reducing the populations access to the resources
– one way in which this competition can be reduced is through resource partitioning.
– Resource partitioning is the dividing up of resources which is available to similar species.
• Resource partitioning is a direct result of niches
43
• The term niche refers to the role of an organism or species in an ecosystem– this includes where it lives, what it eats, how it
reproduces, and how it interacts with other biotic and abiotic things
– the niche occupied by a population in one area may not be the same as that in a different area because the food supply and competitors may be different
– also, the niche occupied by a species may change throughout its lifetime• example of this is a frog growing from a tadpole to an adult
frog each with its own niche
44
Niche
• Broad Niche – able to eat variety of plants or other animals as conditions change– See page 19, 20
• These are generalist species• Narrow niche – specialists that use one or
few resources, helps to be the only one to occupy a certain area
45
• Another example of Niches– Cape May warbler feeds on
insects at the top and tips of the tree.
– Yellow-rumped warbler feeds on insects near the trunk's lower branches and on the ground.
– Black-throated green warbler feeds near the middle of the tree.
– Blackburnian warbler feeds from the outer tips from the middle to the top.
– Bay-breasted warbler feeds from the lower half of the tree away from the tips.
Five warbler species co-exist in the same tree in the spruce forests of Alberta.
46
Niche Summary
• Niche is basically what an organism is and what it does
• A bee is an insect that collects nectar from flowers, fertilizes flowers from pollen transfer and makes honey
• A poplar tree absorbs light for photosynthesis, removes CO2 from the air and releases O2, provides shelter, stabilizes soil, covers the ground with leaves returning nutrients to the soil
47
Questions
• Page 24• Key terms on page 25
48
Question
• Is it always an assumption that any species needs another to survive?
49
Topic 3 “Passing it On” pg 26
• Heritable characteristics– traits passed on from generation to generation
• e.g eye color, hair type, and skin color• Non-heritable characteristics
– are acquired (i.e they are not passed on from generation to generation)• e.g.a person is really good at football but his or her children
will not be born knowing how to play football.
50
• Variations can be effected by environment– height is a heritable characteristic but height can be
effected by diet• e.g in the 19th century people were a lot shorter than they
are now due to poor diet– i.e poor nutrition and lowered variety of food compared to today
51
Asexual and Sexual Reproduction
• Reproduction produces new individuals of a species– this reproduction can produce individuals who are
identical or very different from the parents or parent cell
• Asexual Reproduction– involves only one parent– all offspring are identical to that parent
• i.e the offspring inherits identical characteristics because the parent makes a copy of itself
52
• Asexual Reproduction (Cont.)
– there are several different forms of asexual reproduction such as binary fission, budding, spore production, and vegetative reproduction. (page 26)
• Binary Fission– a cells splits exactly in two, producing two identical
individuals (pg. 27)– only one-celled organisms, such as bacteria, and some
protists, such as amoebas and some algae can reproduce this way
53
Amoeba
54
Electron microscope view of amoeba undergoing binary fission
55
• Budding– the parent produces a small bud, or a smaller version of
itself.• in animals, such as hydra, the bud eventually falls off and
becomes a new individual identical to its parent• in corals (also an animal) the offspring stays attached to the
parent forming a large structure of many identical individuals• Spore Production
– fungi, green algae, some molds and non-flowering plants reproduce this way• spores are similar to seeds but are made by a cell or cells on
a parent that divides• one individual can produce many spores and each spore
develops to be a new identical individual
56
How fungi digest food.
57
Fungus Life Cycle
58
• Vegetative Reproduction– is the reproduction of a plant that does not involve the
making of a seed• i.e if you cut off a piece of some plants and put it in water it
will grow roots and become a new plant• e.g roots of aspen produce a type of shoot that is called a
sucker. If the tree and the sucker become detached then the sucker will grow to be a whole new tree
• again all these individuals are genetically identical to the parent plant
– Most plants are able to reproduce this way (carrots, potatoes…)
59
Cloning (page 29)
• Dolly the sheep• http://www.sciencemuseum.org.uk/antenna/
dolly/index.asp
60
• usually involves two individuals• offspring of sexual reproduction have a mix of characteristics
from both parents• this means that there will always be a mix of characteristics
in each generation (recall: the importance of variability)– most species of animals and flowering plants are to
reproduce this way – this type of reproduction does not always involve a
male and female as we humans define them
Sexual Reproduction
61
Sexual Reproduction
• Sexual reproduction relies on the union of two specialized cells called gametes (sex cells)
62
• A Gamete– is a cell that has only one job and that is to combine
with another gamete during reproduction– In animals male gametes are called sperm cells and
female gametes are called egg cells (ova)• Fertilization
– is the union of the sperm cell and the egg cell during mating
• A Zygote– is the cell created by the joining of the two gametes
63
64
65
– The zygote divides into two cells, then four, then eight, then sixteen and keeps dividing like this in a processes called cleavage
• an Embryo– is a new multicellular life form, resulting from
continued cell division– this process of sexual reproduction from fertilization to
embryo may occur inside the female parent (most mammals) or outside, in an egg
cleavageembryo
66
67
Best of Both Worlds
• Many organisms are able to reproduce sexually and asexually
• Some molds like Rhizopus, produce spores and zygospores which, have genetic material from 2 different sources
• Page 30-31
68
Moldy Bread
• I need volunteers to bring in various breads• Mold lab on page 31
69
Bacterial Conjugation
• Bacteria can actually have a form of “sex”• One bacterium will transfer DNA to another
via a “pilus” • This can lead to genetic exchange and even
antibiotic resistance• See page 32
70
Plants reproduce Asexually and Sexually
• Page 34
71
See page 35
72
• As in animals, sexual reproduction requires the joining of male and female gamete to produce a zygote and an embryo
Sexual reproduction in Plants
pistil
73
• most plants produce both male and female gametes but some only produce one or the other
• Pollen contains the male gametes of a plant• Pollen is found on the stamen, or male part,
of the plant• Ovules contain the female gametes of a plant• Ovules are found in the pistil, or female part,
of the plant• Pollination occurs when pollen is transferred
from the anther of the stamen to the stigma of the pistil
74
75
Sexual Reproduction in Plants
• Page 32- 33
76
• Cross-pollination – occurs when the pollen of one plant is carried to the
stigma of another by wind, water, or animals• e.g bees or butterflies
• Cross-fertilization – occurs when a grain of this pollen produces a long
tube that eventually grows down the style into the ovary that contains the ovules
• The gamete in the pollen grain joins with the gamete in the ovule and a zygote is formed which starts a series of divisions to produce an embryo
77
• Advantages and Disadvantages of Asexual and Sexual Reproduction
• Advantages of Asexual Reproduction– does not require any specialized cells or a way of
bringing gametes together– can reproduce very quickly– takes very little energy
• Disadvantages of Asexual Reproduction– if conditions become unfavorable (change in
environment) whole population can be wiped out• In what type of conditions would Asexual reproduction be
the best?
78
• Advantages of Sexual Reproduction– lots of variations (how does this help?)
• Disadvantages of Sexual Reproduction– takes a lot of energy
• e.g flower plants have to produce all the parts of its flower, as well as pollen and ovules
– takes a lot more time to reproduce than Asexual reproduction
– must have some way for the gametes to meet• e.g either produce lots of pollen (more energy needed) to be
dispersed by wind and water or rely on other means to transport such as animals
79
• Sexual reproduction puts a lot of energy and time into producing offspring and therefore only produce a limited number
• Some plants and animals reproduce both Asexually and Sexually
• How would this be a benefit to the animal or plant?
• e.g Aphids– females produce lots of female young Asexually during the
growing season– near the end of the season females produce both male and
female offspring which reproduce sexually and lay eggs which hatch next summer
80
Questions
• Page 36
81
Make the following charts
• Asexual Chart Summary• Asexual Key• Sexual Summary Chart• Sexual Key
82
Graphing Review
• How to graph data?• Example• How would you graph age and height of a
sample of 25 students in the school?
83
Page 9 Lab
84
Topic 4 “Wearing your Genes”
• Page 37• Science regarding heredity is called
genetics• Different genes can lead to different
variations• Variations can be either Discrete or
Continuous
85
• Discrete variations– are differences in characteristics that have a defined
form• think of a discrete variation being the either/or form of a
characteristic– i.e a cat either has blue eyes or does not have blue eyes– you can roll your tongue or you can’t roll your tongue
• Continuous variations– are differences in characteristics that have a range of
forms• they are not one form or the other they can have many forms
– i.e adult humans can range from 1.2m to 2.1 m in height– squirrels mass can range anywhere from 133g to 249 g
86
Traits can be Dominant or Recessive
• You may have a genetic code for NON-tongue rolling but it is not expressed because it is Recessive
• Dominant traits are expressed instead of the recessive trait
• Clasp your hands…• Which thumb is on top?
87
• See page 40• Dominance and frequency of
traits are not the same• Some populations have
mostly recessive traits expressed
• Some dominant traits are rarely expressed (eg. Polydactyly)
88
Nature vs. Nurture
• Some traits are acquired through the environment the organism is exposed to
• What would Arnold look like if he had no desire to lift weights and had a bad diet???
• See page 42
89
Mutations• A change in your genetic material alters your DNA
and this is called a mutation• X rays, UV light, Cosmic rays and many chemicals
cause mutations…these are called mutagens• Mutations can cause cancer which are cells that
divide uncontrollably and disrupt and can stop the function of the nearby tissue
• Mutations occurring in egg or sperm cells can have severe consequences to the unborn child
• Mutation can also be a good thing if it leads to a new beneficial trait
90
Questions Page 45
91
DNA: Molecule of Life
• DNA is the molecule that acts as a blueprint for all life
• It codes for amino acids which make up proteins and they provide structure and function of an organism
92
• DNA (deoxyribonucleic acid)– a molecule that stores genetic information for heritable
traits and directs the structure and functions of cells– A DNA molecule can be compared to a ladder that has
been twisted into a continuous spiral– Each rung (or step in the ladder) is a pair of the
following four chemicals:• Guanine (G), Cytosine (C), adenine (A), and thiamine (T)
93
DNA in Detail
• http://www.pbs.org/wgbh/nova/genome/dna.html#
• http://www.johnkyrk.com/DNAanatomy.html
94
Modelling DNA
• Page 48
95
– the genetic code is these four chemical “letters” that are arranged into words that the blueprint for all species on Earth
• Chromosomes are packages that contain DNA• Chromosomes are located in the Nucleus of cells
96
• Different species have different amount of chromosomes
• Dogs have 78 chromosomes, Cats have 38, Humans have 46– all of these are organized into pairs so humans have
23 pairs, dogs have 39 pairs and cats have 19 pairs– One chromosome only contains a part of the
information for building that particular species• Genes are responsible for the inheritance of an
organism's characteristics• A single Gene is an uninterrupted segment of
DNA
97
• A chromosome pair carries two chromatids each having the same genes but these genes can have slightly different forms when expressed as a characteristic– Recall: the recessive (weak) gene and the dominant
(bully) gene• These forms are called alleles
– They are usually marked by using an upper case letter for dominant and a lower case letter for recessive
98
Patterns of Inheritance• Purebred versus Hybrid• Purebred
– is organism that has ancestors all with the same form of a trait• e.g. a rhino that only carries the genes for brown is a
purebred rhino for brown• two dominate or recessive alleles (BB or bb)
99
• From the colors of these baby rhinos. Which color is dominate?
– is an organism that was produced by crossing two individuals purebred for different forms of a trait• e.g a purebred brown rhino breeds with a purebred blue rhino
and has a baby rhino that has both genes for brown and blue. This baby rhino is a hybrid.
• one dominate allele and one recessive allele
• Hybrid
100• Example (Purebred X Purebred)
bb
Bb
BB
Bb
Bb Bb
101bb
• Example (Hybrid X Hybrid)
Bb
BbBb
Bb
BB
102
• Example (Incomplete Dominance)
BBCC
BC
103
Cell Division• Recall: Asexual reproduction• What is the final product in Asexual reproduction?
– An individual genetically identical to the parent– How is this done?– If you split a cell in half (i.e. binary fission) won’t you
get half of the Genetic material in each?– To get two identical organisms in Asexual reproduction
the DNA must be doubled before the split• Mitosis is a type of cell division that produces two
identical daughter cells from one parent cell
104
• Mitosis – is cell division in which the daughter cells retain the
same number and kinds of chromosomes as the mother cell.
– Two identical cells from one parent cell
106
• Mitosis – This is another movie on Mitosis– Mitosis 3
107
• What is the final product in Sexual reproduction?– An individual which is a mixture of both parents (a
genetically unique individual)– a mixture means that a male gamete and female
gamete must combine (what is this union called?)
– How does the gamete only have half the genetic material from the mother or father?
• Meiosis– is a type of cell division that produces cells with
only half the DNA of a normal cell– is cell division in which the daughter cells retain
only half the number and kinds of chromosomes as the mother cell.
108
• Meiosis– four daughter cells from one parent cell
109
• Meiosis – This is a movie on Meiosis– Meiosis 2– Meiosis
Key Terms
• Somatic cells are the cells that replicate by mitosis (2n = chromosomes are in pairs or are “diploid” cells)
• Gametes or “sex cells” are the products of meiosis (n = non paired chromosomes or are haploid cells)
110
111
Homework
• Questions• Page 45• Activity Page 38• Investigation page 44