Science 9: Unit 1 - Biodiversity Notes

Science 9: Unit 1 - Biodiversity Topic 1.1 - Variety of Life on Earth

Biodiversity refers to the variation in nature and how the interactions between living things are vital.   All living things have these five characteristics: - Ability to reproduce - Made up of cells - Need energy - Grow and develop - Have adaptations to survive   Elements of Biodiversity:   Species: A group of organisms that are similar and can reproduce with each other Ecosystem: The interactions of living things in a certain place Eg. Deserts, forests Genetic Diversity: Genetic varieties of a species Eg. Size or shape of an animal in a species Species Diversity: Number of species in an ecosystem Ecosystem Diversity: Variation among landscapes and communities   There is more diversity at the equator because of the warmer and calmer climates.   Classifying Organisms:   All organisms are classified by Kingdom, Phylum, Class, Order, Family, Genus, Species Remember it using "Killing People 'Cause Orphans Froze Grandma Stephanie"   Eg. A Dog K: Animalia P: Chordata C: Mammalia O: Carnivora F: Canidae G: Canis Species: Canis Familiaris   The five Kingdoms: Plantae, Animalia, Monera, Protista, Fungae

Science 9: Unit 1 - Biodiversity Topic 1.2 - Relationships between Species

Competition: Intra-species Competition -  Competition between organisms of the same species   Interspecies Competition -  Competition between organisms of different species   Population: A group of the same species in the same area Community: A group of populations of different species Niche: Describes the inter-relationships of a species - Broad Niche: Can eat many things to survive, high population, little density, "Generalists" - Narrow Niche:  Only has adaptations to eat few things to survive, low population, high density, "Specialists", only in tropical regions   Resource Partitioning: Competing for resources by accessing it differently from the same source  

Symbiosis: Two or more organisms living in a long term relationship  - Mutualism - Both organisms benefit from the relationship - Parasitism - One organism is harmed and the other is benefitted - Commensalism - One organism is benefitted and the other isn't affected   Interdependence: When two organisms depend on each other Eg. Predator-prey relationships   Food Chain: One long string that demonstrates how organisms consume each other Food Web: A mind map that demonstrates how organisms consume each other 

Science 9: Unit 1 - Biodiversity Topic 1.3 - Variation within Species

Variation: The differences within a given species. Higher levels increase the chance of survival, as they can overcome disasters. - Discrete: Refers to something that has a defined form, either/or Eg. Attached earlobes or not - Continuous: There are a range of possible outcomes Eg. Height, shoe size   Variations in the environment aren't heritable but can change traits   Adaptations: - Behavioural: Mental behaviours of a species Eg. Migrating birds - Structural: Physical characteristics of a species to survive in a certain environment Eg. Giraffes grew longer necks   Natural Selection: The environment selects which species will live and which ones won't. Organisms that can adapt to new or different surroundings faster have a higher chance of surviving. Those who cannot adapt fast have a lower chance of surviving. Eg. Male giraffes battle each other with their necks to see who is the strongest. The strongest ones get to mate, which means that only the "strong" genes get passed to the next generation.   Traits: Characteristics of an organism Eg. Height, size, hair colour - Heritable characteristics: Characteristics that are passed between generations Eg. Eye colour - Non-heritable characteristics: Characteristics that are acquired and not passed between generations Eg. Piano skill    

Science 9: Unit 1 - Biodiversity Topic 2.1 - Asexual and Sexual Reproduction   Asexual Reproduction: Involves only one parent, offspring are identical to that one parent. - Budding: Smaller version of parent detaches and is clone of parent Eg. Yeast - Binary Fission: A cell splits in two identical cells(only in one-cell organisms) Eg. Bacteria - Spore Production: Similar to seeds but only made by one parent Eg. Mould - Vegetative Reproduction: Doesn't involve a seed, such as cuttings, runners, grafting Eg. Potatoes, strawberries   Advantages - Only clone of parent, lots of offspring, less energy needed Disadvantages - Exact clone(nothing new), can be wiped out easily, less variation   Sexual Reproduction: Reproduction with two individuals, offspring has a mix of genes from the parent. In Plants -  - Gamete: Has 1/2 DNA, sperm(male) and egg(female) cell - Fertilization: The union of the sperm and the egg(sperm penetrates egg) - Zygote: After joining, it is the first cell of the new organism - Cleavage: The process of dividing into many cells - Embryo: Early development of multicellular lifeform   In Animals -  - Pollen: Contains male gametes, found in stamen   - Stamen: Has anther and filament - Ovule: Contains female gametes, found in pistil/carpel    - Pistal/Carpel: Has stigma, style, ovary, ovule - Pollination: Pollen is transferred from the anther to the stigma  

Cross Pollination: Pollen is passed between different plants Cross Fertilization: Pollen produces long tube to the female parts of the plant   Advantages - Lots of variations Disadvantages - More energy and time needed, limited offspring  

Science 9: Unit 1 - Biodiversity Topic 2.2 - Transmitter of Genetic Code   Genetics: The study of how characteristics are passed from one generation to the next DNA (Deoxyribonucleic acid): A molecular blueprint for a living thing. Found in the nucleus. Shaped like a helix. It is made up of four molecules: - Adenine - Thymine - Guanine - Cytosine These molecules arrange themselves in different orders like an alphabet, called the Genetic Code.   Chromosomes: Packets of information that determine the traits of an organism. Humans have 46 pairs(23 individual) Genes: A segment of DNA that are responsible for inheritable characteristics. Alleles: Variations of possible DNA sequences in genes (Brown: Dominant, Blue: Recessive)   Mitosis: 1 division, ends with two new cells that are identical with all chromosomes. This happens in growth and repair cells. Steps to Mitosis: Prophase - DNA doubles Metaphase - Lines up in middle Anaphase - Pulls DNA apart and splits Telephase - Two new cells   Advantages - Fast, No partner needed, Less energy needed Disadvantages - Identical, less variation   Meiosis: 2 divisions, ends with four cells with random amounts of half DNA. Only happens in sex cells Steps to Meiosis: Prophase I - DNA doubles and mixes Metaphase I - Lines up in middle Anaphase I - Pulls DNA apart and splits Telephase I - Two new cells Prophase II - DNA doubles and mixes Metaphase II - Lines up in middle Anaphase II - Pulls DNA apart and splits Telephase II - Two new cells   Advantages - More variation Disadvantages - More energy and time needed, Requi    

Science 9: Unit 1 - Biodiversity Topic 2.3 - Patterns in Inheritance   Dominant: Trait that is always expressed, not too common Recessive: Trait that is only expressed if other recessives are there, always overpowered by the dominant, pretty common Purebred(homozegeous): Parents were most likely from a long line of ancestors who only have all recessive or all dominant Hybrid(heterozegeous): Have a mix of dominant and recessive traits   Phenotype: Observable traits resulting from genes Genotype: Consists of two letters(capital = dominant) that represent an allele Punnet Square: Tool used to predict certain genes

Incomplete Dominance: Results in a phenotype that is a blend of allele pairs (Red + Blue = Purple) Codominance: Results in a phenotype that shows both traits (Red + Blue = Red and Blue) Multiple alleles have more than 2 variations Environmental factors can also affect DNA.

Science 9: Unit 1 - Biodiversity Topic 3.1 - Reduction and Conservation of Biodiversity   Biodiversity is being reduced on Earth. Due to many human activities(Habitat Destruction, Introduction of Non-native Species, and Over-hunting). Some natural causes can also affect things(Volcano eruptions, floods, fires, starvation, disease, overspecialization)   Threatened: The species is soon to become endangered Endangered: The species are at risk of going extinct Extirpation: The disappearance of a species from a certain area Extinction: The disappearance of a species from the entire planet   Overspecialization: An organism has too little to rely on to survive Eg. Panda (bamboo is rare)   To Reduce our Biological Footprint we have In-situ Conservation and Ex-situ Conservation:   In-situ Conservation: The conservation of biodiversity within the species' natural habitat Eg. National Parks Ex-situ Conservation: The conservation of biodiversity outside the species' natural habitat Eg. Zoo

Science 9: Unit 1 - Biodiversity Topic 3.2 - Selecting Desirable Traits   Biodiversity: is the process of intervention to get desirable results - Clone: Producing populations of genetically identical individuals - Artificial Insemination: Artificially joining the male and female gametes - In-Vitro Fertilization: Male and female gametes are placed in a controlled environment and forced to fertilize - Genetic Engineering: Directly altering the DNA of an organism