1. SBI3U
Oct 2, 2014

2. Things to note: Agenda D2L course not online yet
6:30- 6:50. Set up, study previous classes notes.
6:50- 7:20. Quiz + Break
7:20-8:50 Lecture + Break
8:30-9:30 Self study/ Hand in Dichotomous key
D2L course not online yet
Workbooks being sold $20 each
Exam: Jan 15th
Drop Deadline: Dec 4th

3. Presentation title slide

4. 1.2 Determining How Species Are Related
UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.2
1.2 Determining How Species Are Related
Modern classification uses morphological similarities and evolutionary history to assign a species to taxa.
Hypotheses about the evolutionary history and relationships among different species are made based on three types of evidence:
anatomical
physiological
DNA
Continued…

5. Determining How Species Are Related
UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.2
Determining How Species Are Related
Species that have many anatomical, physiological, and molecular (DNA) characteristics in common are thought to share a common evolutionary ancestor.

6. Anatomical Evidence of Relationships
UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.2
Anatomical Evidence of Relationships
Anatomy is the study of the structure and form of organisms (including internal systems). It is a branch of morphology and further helps scientists determine evolutionary relationships among species.
These bone structures are similar even though the limbs look different. Over millions of years, the limbs have changed to better suit swimming, flying, running, or grasping, but the overall arrangement of bones and similarities indicate a shared evolutionary history.

7. Physiological Evidence of Relationships
UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.2
Physiological Evidence of Relationships
Physiology deals with the physical and chemical functions of organisms, including their biochemistry and internal processes. Taxonomists use the data on the physical and chemical functions of an organism to classify it.
Guinea pigs and mice were once both classified in the order Rodentia. An analysis of proteins, including insulin, showed that guinea pig insulin is very different from that of typical rodents. Guinea pigs were reclassified into a taxon of their own.

8. DNA Evidence of Relationships
UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.2
DNA Evidence of Relationships
New technology has made it possible to conduct genetic analysis and de-code the sequences of nucleotides in DNA. DNA from different species can be compared to determine relationships. 
In some cases, new DNA evidence has meant that classifications based on morphological, physiological, or other evidence have to be restructured.
Fungi and plants are superficially similar—they do not move, and they grow out of the ground. However, DNA evidence suggests that fungi are more closely related to animals than to plants.

9. Phylogenetic Trees UNIT 1 Chapter 1: Classifying Life’s Diversity
Section 1.2
Phylogenetic Trees
A phylogenetic tree is a branching diagram used to show the evolutionary relationships among species.
Study the phylogenetic tree. To which other organism is Cervus elaphus most closely related? At what rank and taxon are they related?
The animals shown here are all part of the order Artiodactyla.

10. Phylogenetic Trees
Root of the tree (or base depending on type) represents the oldest ancestral species
Upper ends or furthest branches represent present day species
Forks in each branch represent points in the past were ancestral species split, evolved or changed overtime to form a new species

12. 1.3 Kingdoms and Domains UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.3
1.3 Kingdoms and Domains
The second most general rank, kingdom, includes six different taxa. There is incredible structural diversity (internal and external forms) within the kingdoms even though species are grouped.
Advances in microscopy and molecular biology have increased the number of kingdoms from two in the 1800s to six in Classification at the kingdom level is based on general internal and external similarities, but it begins with the two basic cell types on Earth.
Structural Diversity: the variety of both external and internal structural forms in living things
great variation in their cell structure and body morhpology

13. Two Major Cell Types UNIT 1 Chapter 1: Classifying Life’s Diversity
Section 1.3
Two Major Cell Types
There are two major cell types: prokaryotic and eukaryotic.
Which type of cell might have originated first,
prokaryotic or eukaryotic? Explain your answer.
What other differences can you observe?

14. Main Characteristics of Kingdoms
UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.3
Main Characteristics of Kingdoms
When classifying only to the kingdom rank, the following characteristics can be used:
number of cells (unicellular or multicellular)
cell wall material (if present)
nutrition (autotroph or heterotroph)
primary means of reproduction (asexual or sexual)
Continued…

15. Main Characteristics of Kingdoms
UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.3
Main Characteristics of Kingdoms
An autotroph captures energy from sunlight/abiotic substances. A heterotroph obtains energy by consuming other organisms.
Try to use the characteristics above to identify the kingdom for each organism. Infer where necessary.

17. 1.4 Classifying Types of Biodiversity
UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.4
1.4 Classifying Types of Biodiversity
Genetic diversity
Species diversity
There are three important ways of studying biodiversity.
Ecosystem diversity
Continued…

18. Classifying Types of Biodiversity
UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.4
Classifying Types of Biodiversity
Genetic diversity is the variety of heritable characteristics (genes) in a population of interbreeding individuals.
Species diversity is the variety and abundance of species in a given area.
Ecosystem diversity is the variety of ecosystems in the biosphere.

19. Genetic and Ecosystem Diversity
UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.4
Genetic and Ecosystem Diversity
Genes: are made up of DNA, act as instructions to make molecules called proteins
A gene pool is the sum of all the versions of all the genes in a population. The larger the gene pool and genetic diversity, the better the chances of species survival despite environmental pressures or changes (diseases, for example).
The population of Tasmanian devils (Sarcophilis harrisii) has been severely reduced by cancer. A lack of genetic diversity made the animals vulnerable to disease.

20. Ecosystem Diversity
On a much larger scale, ecosystem diversity refers to the variety of ecosystems in all sizes from a plant to an entire biome. The health and sustainability of the biosphere can be measured by the richness of ecosystem diversity.
Ecosystem: The living (biotic) and non-living (abiotic) factors and the interaction between them

21. Ecosystem Services and Human Activity
UNIT 1
Chapter 1: Classifying Life’s Diversity
Section 1.4
Ecosystem Services and Human Activity

22. 2.1 A Microscopic Look at Life’s Organization
UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.1
2.1 A Microscopic Look at Life’s Organization
All species of living organisms, whether unicellular or multicellular, are comprised of cells and can be studied using a microscope. Scientists also investigate and classify viruses, although they are not considered alive since they cannot live outside of cells. Viruses differ from prokaryotic and eukaryotic cells in that:
they are dependent on the internal
physiology of cells
they are not cellular and thus lack cytoplasm, organelles, and cell membranes

23. Classifying Viruses UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.1
Classifying Viruses
size and shape of the capsid (protein coat surrounding genetic material)
shape and structure of the virus
type(s) of diseases the virus causes
genome (set of genes) and type of genetic material (RNA or DNA)
method of reproduction
Scientists classify viruses by using each one’s unique characteristics, including:

24. Reproduction in Viruses
UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.1
Reproduction in Viruses
Viruses undergo replication inside a host cell. Some viruses replicate by means of a lytic cycle, where they quickly attach, enter, replicate, assemble, and release from a cell, killing the cell in the process.
Other viruses replicate by means of a lysogenic cycle, where they enter and then attach their DNA to the host’s chromosomes. Now referred to as a provirus, it can lie dormant within the host chromosome until it re- activates and continues with the lytic cycle.
Continued…

25. Viruses and Disease UNIT 1 Continued…
Chapter 2: Diversity: From Simple to Complex
Section 2.1
Viruses and Disease
In multicellular species, lytic viruses burst from host cells and infect neighbouring cells. Host organisms that are already damaged are affected more rapidly.
Lysogenic viruses may not cause any immediate effects on the host organism. HIV (human immunodeficiency virus) is an example of both a lysogenic virus and a retrovirus.
Continued…

26. 2.2 Comparing Bacteria and Archaea
UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.2
2.2 Comparing Bacteria and Archaea
Comparisons of cell type, morphology (shape), aggregation, nutrition, habitat, and reproduction show similarities and differences between the two domains.
Continued…

27. Comparing Bacteria and Archaea
UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.2
Comparing Bacteria and Archaea
Similarities
prokaryotic
similar shapes of coccus (spheres), bacilli (rods), and spiral cells
for energy, species either consume other organisms or use inorganic compounds
species live in aerobic or anaerobic habitats
both found in extreme environments; more archaea live in extreme habitats (extremophiles), while more bacteria live in moderate habitats (mesophiles)
reproduce by binary fission and can exchange genetic content by conjugation
Continued…

28. Three Types of Extremophiles
UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.2
Three Types of Extremophiles
Acidophiles live in volcanic craters
and mine drainage lakes, enduring
pH levels lower than 3.
Example: Archaea Picrophilus
Halophiles live in salt lakes and
inland seas, enduring salt concentrations
above 20%.
Example: Archaea Halococcus
Thermophiles live in hot springs and deep sea vents, enduring temperatures over 100ºC.
Example: Archaea Methanopyrus

29. Reproduction of Bacteria and Archaea
UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.2
Reproduction of Bacteria and Archaea
Reproducing Asexually
Since both domains are prokaryotic and lack a nucleus, both reproduce asexually by binary fission. As a cell grows, it makes a copy of its single chromosome. After elongating and separating the two copies, the cell builds a septum between and splits into two identical cells.
Continued…

30. Reproduction of Bacteria and Archaea
UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.2
Reproduction of Bacteria and Archaea
In less favourable conditions, DNA can be exchanged instead of reproducing by binary fission. In conjugation, one cell links to another by a pilus (tube) and transfers a copy of some or all of the chromosomes.
Continued…

31. Bacteria, Human Health, and the Environment
UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.2
Bacteria, Human Health, and the Environment
Some bacteria can harm human health. Examples include:
Clostridium botulinum causes food poisoning
Streptococcus pyogenes causes strep throat
Streptococcus mutans causes tooth decay

32. Bacteria, Human Health, and the Environment
UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.2
Bacteria, Human Health, and the Environment
Bacteria are decomposers. They break down organic molecules and release carbon, hydrogen, nitrogen, and sulfur, thereby supporting those nutrient cycles. Through the process of photosynthesis, cyanobacteria are major producers of oxygen gas on Earth.
Some species in Archaea have enzymes that are of special use to humans because they can withstand extreme temperatures, salinity, and acidity. Biotechnologists have been able to use some of these enzymes for various procedures in DNA research.

33. 2.3 Eukaryotic Evolution and Diversity
UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.3
2.3 Eukaryotic Evolution and Diversity
About 2 billion years ago, eukaryotes evolved and this led to an increase in the diversity of life on Earth.
These organisms are more complex than prokaryotes. They include more genes, allowing for greater cellular diversity in terms of size, shape, mobility, and specialized functions.
Scientists examined the important question of how eukaryotic cells evolved and have come up with some theories supported by observations and evidence.

34. UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.3
Endosymbiosis
The theory of endosymbiosis suggests that eukaryotic cells evolved from symbiotic relationships between two or more prokaryotic cells.
Although one prokaryotic cell engulfed a different, simpler prokaryotic cell, the engulfed cell survived and became part of the host cell.

35. Chloroplasts and Mitochondria
UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.3
Chloroplasts and Mitochondria
Chloroplasts and mitochondria may have been free-living prokaryotes engulfed by larger prokaryotes. They continued to perform their cellular activities while surviving and serving the host cell. A comparison of chloroplasts, mitochondria, and prokaryotes shows:
similar types of membranes
similar types of ribosomes
each reproduces by binary fission
each contains circular chromosomes
gene sequences match  

36. Multicellularity UNIT 1
Chapter 2: Diversity: From Simple to Complex
Section 2.3
Multicellularity
Based on fossil evidence, scientists think that large, complex eukaryotes first developed about 550 million years ago. They have also found fossils of simple red algae in the Arctic that date multicellular eukaryotes as far back as between 1.2 and 1.5 billion years ago.
Scientists hypothesize that the first multicellular organisms arose from colonies created by individual cells that divided. Genes within these cells contained
instructions for some cells to
become specialized. With the
passage of time, groups of cells
developed different functions.