Unit A All Notes PDF

Selecting Desirable Traits Unit A- Section 4.2  Artificial Selection ✘ Artificial Selection is the process of selecting and breeding individuals with desirable traits. ✘ Instead of “Natural selection”, humans make the choices. ✘ We...

Selecting Desirable Traits Unit A- Section 4.2  Artificial Selection ✘ Artificial Selection is the process of selecting and breeding individuals with desirable traits. ✘ Instead of “Natural selection”, humans make the choices. ✘ We can use this for certain animals (pets) or plants (crops). Biotechnology ✘ Biotechnology is any technology that allows us to influence the biology of reproduction and genetic inheritance. ✘ Generally, it is used to speed up the adaptation or development of species.  Cloning Positives: Negatives: 1.Can be used to “customize” 1. No variation! Every individual is offspring of certain individuals (lab the exact same! grown organisms). 2. Ethics- Is it right to clone 2. Recreation of specific tissues- growing new kidneys for people people or animals? with kidney disease. 3. Can it be used for evil 3. Researching many different purposes? Yes! things by growing what is needed in a lab.  Creating Clones ✘ We can clone plants by taking cuttings of plants and replanting them. ✘ We can also take cells from an organism and grow them in a petri dish in a lab.  Artificial Reproductive Technology In Vitro Fertilization: In IVF Artificial Insemination: Also the sperm and egg are taken known as AI is when sperm is put from parents and fertilized in a into a female’s reproductive lab (petri dish, bottle, etc.). Once system using tools. Used in embryos exist they are placed breeding cows or horses. into a female to grow. Why? Why? IV󰉇 󰈾󰈯 󰉚C󰈜I󰈮󰈯!  Genetic Engineering: Technology that manipulates the DNA of an organism. Designer Babies or removing genes that code for diseases. Genetic Engineering We used genetic engineering to make bacteria grow substances we need:Insulin, epinephrine, etc We have taken a gene from bacteria and created plants with genes that make them poisonous to pests but not to humans= no pesticides in crops!  Unit A- Section 4.1 Reduction of Biological Diversity  Extinction Extinction is the disappearance of every individual of a species from the entire planet. Extinction is a NATURAL part of Earth’s history. Only about 1% of all species EVER are alive today! Sometimes extinctions are caused by natural disasters (asteroids) but most happen over time. The rate at which species are going extinct is increasing! Extirpation Extirpation is a local extinction of a species. Not the species in its entirety. So, if bears from a certain area go extinct, but exist elsewhere on the planet, it is an extirpation.  As species die (go extinct), the overall genetic diversity of the planet decreases.  Natural Causes of Extinction and Extirpation We know that variability in traits can save a species from extinction. But if species have variability, how do they go extinct? 1.Environments change too quickly for natural selection to work. 2.Disease 3.Catastrophic events (asteroids, earthquakes, etc.) Overspecialization Sometimes, organisms have adaptations that make them TOO specifically set up for their environment. This is called overspecialization. Example🡪 Pandas ONLY eat bamboo. This means they can ONLY live where bamboo grows. Overspecialization makes animals more likely to go extinct.  We cause rapid changes to environments in many ways: Human Causes Extinc o f 1. Construction tions and Extirpa 2. Deforestation tions 3.Growing Crops 4.Pollution (pesticides/fertilizers)  Introduction of Non-Native Species Migrating humans bring species they need with them. Cows and horses were brought to North America by Europeans. Corn was brought by First Nations people from South America. Or species “hitch a ride”. Ex. Bacteria, seeds caught in ships, tires, etc.  Non-Native Species and Competition When non-native species use the same resources as a native species they create competition. Competition means less resources for native species. Populations almost always go down.  Over-Huntin g Humans often hunt too much of a species, causing extirpation in areas. Sometimes we extirpate species on purpose (gophers, pests, etc.) Check and Reflect! page 65  Patterns of Inheritance Unit A- 3.3  Early Inheritance Experiments Scientists have tried to control breeding for much longer than we’ve known about chromosomes and genes. They tried to make animals inherit certain traits but weren’t always successful. By keeping records of failures and successes they started to notice patterns on how traits are inherited.  Purebreds To ensure an organism inherited a specific trait or characteristic, the breeders would use only individuals with the same 2 alleles. Remember: each organism has 2 copies of each gene (1 from mom and 1 from dad).  Purebreds These organisms were known as purebred. So a cat that comes from a long line of white hair ONLY ancestors is likely a white-haired purebred cat.  Hybrids Hybrid organisms come from crossing 2 purebred parents that have different traits. Typically we create hybrid organisms from a purebred dominant parent and a purebred recessive parent.  Hybrids The hybrid offspring has 1 copy of the dominant allele (black fur), and 1 copy of the recessive allele (white fur)!  Dominant Traits Dominant traits are the traits that are GUARANTEED to be seen if the organism has the allele. They take precedence over other forms of the trait.  Dominant Traits Black fur is dominant. If the father gives an allele for black fur to each kitten they HAVE to have black fur! Even though they also have a white fur allele, it is ignored or suppressed.  Recessive Traits Recessive traits are traits that only show through when they are the only alleles present. Recessive traits do not show through when there are dominant alleles, so there must be 2 recessive alleles.  Recessive Traits In crosses with 2 hybrid parents, they will produce the occasional recessive offspring. Punnett Squares Punnett squares are used by geneticists to determine the appearance of the offspring made by 2 parents. We can determine the appearance by crossing the genes of the parents.  Test it! B B If we cross a purebred brown-eyed parent with a purebred brown-eyed parent B what will happen? B= allele for brown (dominant) B  Test it! b b If we cross 2 purebred blue-eyed parents, what would their children look b like? b= allele for blue (recessive) b  Test it again! What if we cross 2 hybrid B b parents? BB- 2 dominant- brown eyes B Bb- 1 dominant/ 1 recessive brown eyes bb- 2 recessive b blue eyes  Incomplete Dominance Sometimes, traits can blend together to produce a trait somewhere in the middle! This is known as incomplete dominance.  Codominance Sometimes, both traits are expressed in the organism at the same time. For example, cows will have patches of a different color on their coats. This is known as codominance.  Or something totally different! Sometimes, an offspring looks totally different from their parents! This can be because a trait is affected by more than 1 gene or there has been a mutation! Cell Division Unit A- Section 3.2  Cell Division and Asexual Reproduction Remember binary fission. A single-celled organism divides itself in 2. But it can’t split its DNA in 2🡪 the cells would die without enough information.  Cell Division and Asexual Reproduction SO… the cell makes a copy of its DNA and for a SHORT time, it has twice as much DNA as usual! When it divides into 2 cells each has its own copy of the DNA!  MITOSIS When cells in multicellular organisms divide to produce new cells with the same number of chromosomes it is called mitosis. Mitosis occurs in body cells of multicellular organisms for growth and repair 🡪 getting taller or healing cuts! MITOSIS MITOSIS IN REAL LIFE HeLa cell undergoing mitosis  Mitosis Creates Identical Copies! Each cell that comes from mitosis is the exact same! These identical daughter cells have the same DNA as their parent cell. Meiosis Meiosis is a different type of cell division that creates gametes (male and female sex cells) This happens in sexually reproducing organisms → like us! Meiosis It creates cells with half the amount of chromosomes compared to body cells. This is why the male and female gamete must join together to form a zygote! Steps of Meiosis Step 1: The parent cell makes a perfect copy of its DNA. Each chromosome is duplicated (there are now 2 of each chromosome) → chromosome pair Steps of Meiosis Step 2: The cell divides in 2, with each have having a chromosome pair. NOTE: The chromosome pair in each cell is NOT the same Steps of Meiosis Step 3: The cells divide again, without duplicating chromosomes. This gives us 4 daughter cells with half of the original genetic information.  Steps of Meiosis These are sperm and egg cells! → Each has a unique combination of DNA No sperm or egg is the same! chromosome pair chromosome Mitosis vs Meiosis Rap Battle! | SCIENCE SONGS Check & Reflect Complete page 48 Check and Reflect Questions #1-8  9th grade DNA: Transmitter of Genetic Code  DNA is A-OK! Why do you look the way you do? What gave your body instructions to turn out the way you did? Your DNA (deoxyribonucleic acid)!  What is DNA? ► All living organisms have DNA that codes their genetic information. ► All inherited traits are passed down in DNA. ► DNA is stored in the nucleus of cells. Animal cell Plant cell BASE PAIRS DNA looks like a twisted ladder. It has a backbone of sugar and phosphates and the rungs are made of pairs of 4 chemical “bases”. THYMINE ADENINE GUANINE CYTOSINE (T) (A) (G) (C) Always pair together. Always pair together. The pairing of these bases is known as the genetic code. Similar to the 26 letters of the alphabet, rearranging the 4 bases describes how to make every organism.  CHROMOSOMES A si󰈝󰈈l󰈩 󰈻󰉄r󰇽󰈝󰇶 of D󰈰A 󰉒o󰉉󰈘d 󰈻󰉄re󰉃󰇸h 󰈡󰉏󰇵󰈹 2 me󰉃󰈹󰈩s. So it’s packaged in tightly coiled structures called chromosomes. Our chromosomes come in pairs (which means we have 2 copies of every gene too!)  CHROMOSOMES A si󰈝󰈈l󰈩 󰈻󰉄r󰇽󰈝󰇶 of D󰈰A 󰉒o󰉉󰈘d 󰈻󰉄re󰉃󰇸h 󰈡󰉏󰇵󰈹 2 me󰉃󰈹󰈩s. Each human cell has 46 chromosomes (23 pairs). EXCEPT GAMETES (because they are ready to be paired with another gamete). GENES Base pairs are assembled to form genes, which are segments of DNA that code for individual traits. Like chromosomes, genes come in pairs that carry DNA instruction for the same trait. Offspring inherit gene pairs from both parents. GENES Genes come in different forms called alleles. For example, fruit flies have 2 possible leg length allele: short leg or long leg. A fruit fly will inherit one gene from its mother and one from its father.  Fun Facts Dogs have 78 chromosomes! 1 gram of DNA holds as much information as 1 trillion CDs! If you unravelled all the DNA in your body you could reach it to the moon… 6000 times. It would take you 50 years to type the entire human genome if you typed at a speed of 60 wpm and worked 8 hours a day, every day!  02 Check & Reflect Page 45 # 1-8 Types of Sexual Reproduction  Sexual Reproduction in Animals Occurs from specialized sex cells called gametes. Male gamete: sperm cells Female gamete: egg cells (ova) 1. When a sperm and egg cell meet (during mating) it is called fertilization. 2. The cell that they create when joined is known as a zygote. → The zygote then splits into 2 cells. 3. The cells divide again and again in a process called cleavage. 4. Cleavage continues until we have a multicellular embryo. The new individual will be a mix of both parents. Sexual reproduction promotes variation!  Sexual Reproduction in Plants Flowers and plants can reproduce sexually. Plants that reproduce sexually have gametes too! Male gamete: Pollen Pollen is found on the stamen. The stamen is the male part of the plant. Female gamete: Ovules Ovules are found in the pistil. The pistil is the female part of the plant.  Pollination Vs. Fertilization Pollination occurs when pollen is transferred from the anther of the stamen to the stigma of the pistil. Fertilization occurs when the male and female gametes meet. Cross-pollination happens when pollen of one plant is carried to the stigma of another plant. 🡪 by birds, bee, etc. Cross-fertilization happens when a grain of pollen from another plant produces a tube that grows down the style into the ovary of the plant. The pollen grain and ovule meet and a zygote forms. The zygote then begins many divisions to become an embryo. In most plants the embryo is encased in a seed.  Cross-fertilization will give the plant characteristics from both parent plants. Plants can self-fertilize. BE AWARE: Pollination and cross-pollination are ONLY the TRANSFER of pollen. This may not result in an embryo if no fertilization occurs. WATCH IT!  SEXUAL REPRODUCTION ADVANTAGES DISADVANTAGES Advantages of Sexual and Asexual Reproduction Sexual Reproduction Asexual Reproduction -Allows for lots of -Does not require any variation specialized cells -Protects species from -Doesn’t need gametes environmental wipeouts to merge (extinction) -Can be very fast Disadvantages of Asexual and Sexual Reproduction Sexual Reproduction Asexual Reproduction -Takes a long time -No variation -Takes a lot of energy -More likely for environmental wipeout Asexual and Sexual Reproduction  Reproduction and Variation Reproduction creates new individuals of a species. The type of reproduction decides on the level of variation in individuals. There are 2 types: → Asexual Reproduction → Sexual Reproduction TYPES OF ASEXUAL REPRODUCTION Watch it!  Binary Fission ONLY occurs in one-celled organisms. Ex. Amoebas, some bacteria Cell splits exactly in two 🡪 2 identical copies  Budding Occurs in yeast, coral, hydra, etc. The organism creates a “bud”, a small version of itself. Sometimes this detaches, sometimes it stays attached. Spore Reproduction Occurs in fungi, moulds and plants like ferns. Spores are produced- they are similar to seeds but are made by division of parent cells, not by the union of 2 cells. Individuals produce MANY spores.  Vegetative Reproduction Most plants can do this. Used by potatoes, tulips, etc. Needs no seed formation. Cuttings, runners, and rhizomes are all examples.  ASEXUAL REPRODUCTION ADVANTAGES DISADVANTAGES A Closer Look at Variation Unit A- Section 2.1  Variation is the Spice of Life! Scientists study variation very closely. They look at: → How characteristics are passed from one generation to the next → How characteristics show up in individuals → How environment affects variation  Heritable and Non-Heritable Characteristics Heritable Characteristics: Passed from generation to generation. Inherited from parents. Non-heritable characteristics: Not passed to offspring. Also known as acquired characteristics.  Sort Them! Flower Petal Colour Hair Colour Height Heritable Sickle Cell Anemia Scars Widow’s Peak Non- Heritable Ability to Roll Tongue Eye Colour Ability to Juggle Ability to Golf  HeritableHave Discrete characteristics: andanNon-Heritable either/ or option (or a limited amount). Characteristics Continuous characteristics: Many different options for the trait. Could be placed on a spectrum.  Sort Them! Hand Size Hair Colour Height Discrete Sickle Cell Anemia Eye Colour Dominant Hand Continuous Ability to Roll Tongue Skin Tone Ear Lobe Attachment Ability to Golf Drank caffeine often 4’10” 4’8” 5’11” 5’1” 5’3” Very Variation and the Environment healthy smoker Certain traits can be inherited but ALSO affected by the environment. Height can be affected by nutrition or sleep patterns. The amount of sunlight a tree has affects how it grows. Adorable.  Check and Reflect! Page 29 #1-5 Label the heading of your notes with: A2.1 A Closer Look at Variation Var󰈎󰇽󰉃i󰈡󰈞 W󰈏t󰈊i󰈞 Spe󰇹󰈎󰇵󰈼  How 󰇹󰈀󰈞 m󰇵󰈚󰇻er󰈻 󰈡󰇿 t󰈊󰇵 sa󰈚󰈩 󰈼p󰇵󰇹i󰈩󰈼 b󰇵 󰇷iff󰈩󰈹󰇵n󰉃?  Var󰈎󰇽󰇼i󰈘󰈎t󰉘 All species vary slightly. The differences between members of the same species is called variability.  Wh󰉘 i󰈼 v󰈀󰈸󰈏a󰇻󰈎l󰈏󰉃󰉙 im󰈥󰈡󰈹t󰇽󰈝󰉄? When the environment of a species changes variability can save a population. Bac󰉃󰈩󰈹󰈏al Cam󰈡󰉊󰇾󰈘ag󰈩 Res󰈎󰈻󰉄󰇽n󰇹e Cha󰈝󰈈󰈩 󰈏n 󰉃e󰈛p󰈩󰈸󰇽󰉄ur󰈩 Abi󰈗󰈎󰉄y 󰉃󰈢 e󰈀󰉄 diff󰈩󰈸󰇵󰈞t 󰇾o󰈡󰇶  Nat󰉉󰈸󰇽󰈘 Sel󰈩󰇹󰉄󰈏on Natural selection occurs when an environment “selects” which individuals will survive long enough to reproduce. Che󰇹󰈕 󰈀n󰇷 R󰇵󰇿le󰇹󰉄 Page 24- #1-4 In󰉃e󰈹d󰈩󰈥󰇵󰈞de󰈝󰇸󰈩  Rel󰈀󰉃󰈏o󰈞s󰈊󰈎󰈦s All living creatures rely on other creatures for survival. There are many types of relationships. Examples?  S󰇳󰈱BI󰈮󰈠󰈽󰈟 ▶ When animals of different species do things to or with each other it is called symbiosis. ▶ 3 types: Commensalism Mutualism Parasitism 1 organism benefits from Both organisms benefit 1 organism benefits and the an interaction the other from the interaction. organism is harmed. does not. The organism NOTE: This is not that does not benefit it not predation. harmed. a. commensalism b. mutualism c. parasitism a. commensalism b. mutualism c. parasitism a. commensalism b. mutualism c. parasitism a. commensalism b. mutualism Barnacles, unable to move on their own, attach themselves to whales to increase their c. parasitism chances of finding food. Whales are not affected by barnacles. a. commensalism b. mutualism The sea lamprey attaches itself to other fishes by suction. Some of the lamprey’s victims may c. parasitism die, while others live but have a scar where the lamprey attached itself. a. commensalism b. mutualism As the Monarch butterfly feeds, pollen sticks to its body. The butterfly carries the pollen to the c. parasitism next flower it feeds from. Most flowers need this pollen to produce seeds. In󰉃e󰈹s󰈥󰈩󰇸󰈏es C󰈡󰈚󰈦󰇵ti󰉃󰈎󰈢󰈞 When more than one species needs the same resources we end up with interspecies competition. Why is this a problem?  Nic󰈊󰈩󰈼 A niche is the role of an organism in its ecosystem. This includes: → What it eats → What eats it → Habitat → Effect on other populations → Effect on environment Res󰈡󰉊󰈸󰇸e P󰈀r󰉃󰈏󰉄i󰈡n󰈏󰈝󰈈 ▶ Sometimes, species divide up a shared resource. This COULD cause problems. ▶ Species can avoid this by having different behavioural patterns that allow them to share the resource. Rev󰈎󰇵󰉒 Qu󰈩󰈼t󰈏o󰈝󰈼 in your notes Examining Biological Diversity Unit A- 1.1 Biological Diversity ► Biological diversity refers to all the different types of organisms on Earth. ► Scientists usually measure diversity in small groupings. Diversity Between Ecosystems ► In an ecosystem, living things (biotic) share space and interact with nonliving things (abiotic). ► They work together as a system, so 🡪 ecoSYSTEM ► The amount and variety of biotic and abiotic factors can be different in each ecosystem. What biotic and abiotic things are living in the Seton ecosystem? Diversity Within Ecosystems ► When members of the same species live in the same area they are known as a population. ► When populations of different species live in the same area they are known as a community.  Diversity Within Species Members of the same species have the same basic structure but they are NOT identical. ► Examples? Species Distribution There are millions of species of organisms on our planet. These different species are not distributed evenly.  Classifying Biological Diversity Carolus Linnaeus developed a system for naming different species. He used latin because it was the “scientific language”. The system gave each animal a 2 word name. 1st Word 🡪 Genus 2nd Word 🡪 Species Example: Homo sapiens. Thefamouspeople.com The 5 Kingdom Classification System Scientists have used a 5 kingdom classification system for a long time. Animalia Plantae Fungi Protista Monera Yeasts, moulds, Mostly single-celled Animals Plants Bacteria mushrooms organisms  Kingdom Phylum Class Order Family Genus Species This is called taxonomy. Community - Anthropology 101 A way of classifying and organizing every living thing in the world! The 5 Kingdoms Bioninja.com Kingdom Kings Phylum Play Class Cards Order On Family Fancy Genus Green Species Stools SCIENTIFIC CLASSIFICATION SONG (Taxonomy Song) |