Biological Diversity - OCR Past Paper PDF

BIOLOGICAL DIVERSITY Unit A Examining Diversity 1.1 Species: a group of organisms that have the same structure and can reproduce with one another successfully to produce viable offspring Dynamite Liger Examining Diversity Organisms also show great diversity. What is diversi...

BIOLOGICAL DIVERSITY Unit A Examining Diversity 1.1 Species: a group of organisms that have the same structure and can reproduce with one another successfully to produce viable offspring Dynamite Liger Examining Diversity Organisms also show great diversity. What is diversity?  BIOLOGICAL There are many different kinds DIVERSITY of ecosystems on Earth (ponds, sloughs, oceans, mountains REFERS TO ALL etc.) THE DIFFERENT TYPES OF Because they are different, the ORGANISMS ON numbers and types of species EARTH. that live there are different. How many species are there on Earth? Ecosystem: the interactions between living (biotic) and non-living (abiotic) things in a shared environment. Population: members of a species that live in a specific area and share the same resources Community: populations of different species that live in the same area What are some abiotic and biotic factors? There are many different kinds of ecosystems on Earth (ponds, sloughs, oceans, mountains etc.) and because they are different, the numbers and types of species that live there are different. There are three different types of Biological Diversity: 1. Diversity Between Ecosystems: compares different types of ecosystems based on their biotic and abiotic components. Example: 2. Diversity Within Ecosystems: shows the variation of populations within an ecosystem Example: 3. Diversity Within Species: shows how individuals of the same species can be different Example: Species Distribution Species distribution is not the same at all places on our planet. Species Distribution Biological diversity is: - greatest at the equator - greatest number of plant species - rainforests - coral reefs - limited at the poles - lowest in the Arctic and Antarctic https://www.greenroofs.com /2022/10/24/global-biodiversi ty-ranked-which-country-ha s-the-most-flora-and-fauna/ Classification of Organisms Classification of Organisms Swedish scientist Carolus Linnaeus came up with a system for naming and classifying organisms. Why was this important? “The Father of Taxonomy” Classification of Organisms This was so that every scientist in the world would have the same name for the same species. Classification of Organisms Linnaeus’s system is called Binomial Nomenclature, because it uses two words to name each living thing - The first word is the genus name - The second word is the species name Species that are closely related can have the same genus but not the same species. Example: Canis rufus = red wolf Canis lupus = timber wolf Canis latrans = coyote Canis familiaris = domestic dogs Classification of Organisms - The naming is done in latin. - The Genus name has a capital as the first letter and the species name is all lowercase letters. Linnaeus arranged species into groups based on their physical structure rather than on their habitat. Taksinus bambus, nicknamed “bambootula.” Its name honors the Thai king Taksin the Great (1734-1782). The tarantula was discovered by JoCho Sippawa and lives inside bamboo stalks. It is the first known species found on only one bamboo species. It crawls through holes made by other animals and insects or through natural cracks in the bamboo. The snake species, described in a new paper as Tachymenoides harrisonfordi, lives in high-elevation wetlands in the southern regions of Peru. The name choice pays homage to Ford, who not only portrayed Indiana Jones and Hans Solo but is also a committed advocate for nature conservation. DiCaprio’s snail-eating snake (Sibon irmelindicaprioae) is found in Panama and Colombia and was named in honor of actor Leonardo DiCaprio’s mother, Irmelin. When threatened, these small snakes hide their head and produce a musky odor to repel predators Parastratiosphecomyia stratiosphecomyioides Spongiforma squarepantsii Kamera lens Ba humbugi Aha ha Turdus maximus Arcticalymene jonesi 5 Kingdom Classification System In order to classify all organisms we must begin with putting the organism into one of the 5 kingdoms of living things: 1) Animalia: (animals) 2) Plantae: (plants) 3) Fungi: (yeasts, moulds and mushrooms) 4) Protista: (single celled organisms) 5) Monera: (Bacteria) Each Kingdom is then divided: The classification of an organism becomes more specific as you move from Kingdom to species We won’t use the domain Each Kingdom is be divided in to many Phyla, Kingdom King then classes, then orders, then families, then genera, then species. Phylum Philip Class Came Order Over Family From Genus Great Species Spain  DO 1.1 Review #1-8 - page 7-8 Interdependence 1.2 Niche Niche is the role or job of the organisms in the ecosystem. This includes what it eats, what eats it, where it lives, and its effects of populations - Niches can change over time, and can be different for the same species that lives in a different area. Interdependence No species can survive by itself. Each species is dependent on many other species in its environment. Give an example of species being interdependent: We (humans) need oxygen to live, and oxygen is made by plants. Interdependence Food chains and food webs illustrate the relationship between species. Interdependence Species co-existing in an ecosystem will share some kind of relationship. Species do not survive isolated from other organisms. Relationships between species are called interdependence. 1. PREDATOR-PREY RELATIONSHIPS - The size of both populations are kept in check. - If the predators increase, the prey will decrease - Once the prey decreases, many predators will die of starvation - This allows the prey population to increase - This allows the predators to recover, and the cycle continues 1. PREDATOR-PREY RELATIONSHIPS - Reduction of prey population allows members to avoid starvation (less competition) - The weak members tend to be captured, leaving the strong to produce similar offspring. 2. SYMBIOTIC RELATIONSHIPS ▣ Commensalism: one organism benefits and the other is unaffected (0/+) Commensalism Examples: □ eyelash mites □ birds on hippos □ suckerfish 2. SYMBIOTIC RELATIONSHIPS ▣ Mutualism: both organisms benefit (+/+) Mutualism Examples □ Plover birds and crocodiles □ pollinators and flowers 2. SYMBIOTIC RELATIONSHIPS ▣ Parasitism: one benefits and the other is harmed (+/-) Does a successful parasite kill its host? Parasitism Examples □ tape worms □ mosquitos 3. INTERSPECIES COMPETITION - Interspecies Competition: Occurs when two or more species need the same resource (food, shelter etc.). Therefore neither species really wins. - To overcome interspecies competition, the niche or role of a population can change from area to area, depending on their competitors and available food supply. 4. RESOURCE PARTITIONING - The same resource is divided up by similar species  DO 1.2 Review #1-3 - page 11 M, C, P Crown gall disease weakens plants and slows their growth. The bacterium that causes the infection obtains nutrients from the plants. A person is infected with tapeworm from eating raw pork. The tapeworm absorbs nutrients from the small intestine and the person becomes sick. Rhizobia bacteria living in association with plant roots turn nitrogen from the air into compounds the plant can use. The benefit to the bacteria is unclear. The yucca moth lays eggs in the ovary of the yucca flower. At the same time, the moth pollinates the flower. One type of algae lives inside reef building coral. The algae cause the coral to grow faster and the coral provide nutrients that the algae can use. Small plants called epiphytes grow on the branches of rain forest trees without harming the trees. Up in the branches, the epiphytes can get enough light and water, and nutrients from the tree. Lichens are made up of algae and fungi living together. The fungus relies on food provided by the algae. The algae are “housed” and protected from drying out by the fungus. M, C, P P Crown gall disease weakens plants and slows their growth. The bacterium that causes the infection obtains nutrients from the plants. P A person is infected with tapeworm from eating raw pork. The tapeworm absorbs nutrients from the small intestine and the person becomes sick. C Rhizobia bacteria living in association with plant roots turn nitrogen from the air into compounds the plant can use. The benefit to the bacteria is unclear. M The yucca moth lays eggs in the ovary of the yucca flower. At the same time, the moth pollinates the flower. M One type of algae lives inside reef building coral. The algae cause the coral to grow faster and the coral provide nutrients that the algae can use. C Small plants called epiphytes grow on the branches of rain forest trees without harming the trees. Up in the branches, the epiphytes can get enough light and water, and nutrients from the tree. M Lichens are made up of algae and fungi living together. The fungus relies on food provided by the algae. The algae are “housed” and protected from drying out by the fungus. Variation Within Species 1.3  List three examples of variation within a species: Variation Variation within a species is called variability. Variability is important to species when its environment changes. The greater the variation among the individuals, the greater the chance that some survive. Variation These changes in environment include: □ Climate □ New predator □ New disease □ Toxic substance □ Elimination of a food source Red Fox The red fox may have a darker coat than the common red coat and be more conspicuous in fields and woods. But if this fox walks into a new habitat, where there are many black rocks, it’s dark coat may blend in better with its surroundings. This way it would be able to pounce on its prey easier. The fox’s predators (wolves, lynx, etc.) might not spot it so easily. So variation in coat colour will allow different fox populations to survive in different habitats. Antibiotic Resistance Emergence of antibiotic resistant strains of bacteria has allowed bacterial populations with variability to survive antibiotics like penicillin  Earth will Be no More In an attempt to save the human population, classrooms of students have been placed aboard rocket ships and are being sent to various planets in various galaxies. You have arrived! Please stand up  All the initial tests show that it appears to be a planet that humans can inhabit The atmosphere is 50% oxygen. Anyone who does not breathe oxygen, dies (sit down)  There appears to be no animals to serve as food for humans but there are plenty of fruits, vegetables, grains and nuts. Anyone who can not eat any of these will die (sit down) There is some sort of unusual radiation on the planet that seems to affect anyone with blue eyes. They develop debilitating headaches and eventually die. All blue eyed people sit down, you are dead.  There are incredible large flying eagle-like birds with a wing span of 13 meters. They are silent in flight and seem to quickly pick off blonde or black haired humans but brown haired individuals are left alone. All blondes and black haired people are dead now sit down. Everyone standing up survived!!! You have just participated in a simulation of natural selection When there is a change in the environment the organisms of the species that survive are the ones that have the traits that enable them to live in that environment. These organisms will reproduce to continue that species. Natural Selection Proposed by Charles Darwin (1809-1882) and Alfred Wallace (1823-1913) Natural Selection Darwin studied 18 species of finches in the Galapagos Islands. He studied the variation in beak shape and size. He looked for trends in how beak shape and size helped birds survive the best. - On the first island, a short, stout beak was beneficial for eating seeds from the ground. So birds with this beak type were more likely to survive, mate, and pass the short beak trait onto their chicks. - On the second island, a longer pointed beak was more useful to pierce cactus fruit. Likewise this pointy beak trait meant a higher chance of survival, and was passing genetically onto their chicks. Natural Selection “Seeing this gradation and diversity of structure in one small, intimately related group of birds, one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends.” - Charles Darwin Natural Selection Natural selection is when the environmental conditions determine which organisms survive and reproduce. - nature “selects” Darwin suggested that life works by “survival of the fittest” meaning only the “strongest” or the “best” survive. Natural Selection These "fittest" individuals may be due to a structure, such as a thicker coat, deeper roots or smaller ears. Or they might involve a behaviour, such as “freezing” to hide from a predator. Example: The Cliff Swallows of Nebraska Although equally healthy, a severe cold spell killed 30 000 birds or half the population, due to starvation. The survivors were selected because they were larger, more fat, had greater symmetry with their beaks and legs. This allowed them to store more fat and forage with less energy loss. The offspring also showed these characteristics. Natural Selection Whatever the reason, only the organisms that survive and reproduce pass on their characteristics to the next generation. In this way, the environment “selects” the individuals best suited to it, that is the individual best at surviving and reproducing in it.  DO Topic 1 Review #1-9 - page 14-15  Unit A: Biological Diversity Topic 2.0 Topic 2.1 A Closer Variation Look at Variation 2.1  List 3 traits (characteristics) that can be passed down from parents to offspring Heritable vs. Non-heritable Scientists study which variations get passed on from generation to generation. Heritable characteristics: traits that get passed from generation to generation Non-heritable characteristics: characteristics that do not get passed on What are some examples of heritable and non-heritable characteristics? Heritable vs. Non-heritable Heritable: Non-heritable: □ Eye colour □ Dyed hair colour □ Hair colour □ Sun tan □ Skin colour □ Ability to play piano □ Blood type □ Ability to swim □ Height □ Ability to talk Discrete vs. Continuous Discrete variations: usually have only two choices for a characteristic. - You either have the characteristic or you don’t. There are only so many choices. Continuous variation: occurs when there is a range of different forms of that characteristic. What are some examples of discrete and continuous characteristics? Discrete and Continuous ▣ Discrete: ▣ Continuous: □ Eye colour □ Height □ Blood type □ Weight □ Albino □ Pigmentation □ Hitchhiker's of skin thumb □ Intelligence □ Widow’s peak □ Size of hand span Variation and the Environment On average, North Americans are taller today, and have bigger heads than they used to. Why do you think this is? Variation and the Environment ▣ Better nutrition and a wide variety of foods. ▣ Increased use of C-Sections ▣ The environment can limit or enhance an individual’s genetic capabilities. □ However, variations of this type are NOT heritable. Variation and the Environment ▣ Sometimes variations can be based on where the organism lives. For example, people who live in sunny places, like Hawaii, tend to have darker skin than people who live in other places. □ This characteristic is non-heritable. Quickly clasp your hands together, interlocking your fingers. Quickly clasp your hands together, interlocking your fingers. Now, look to see which thumb is on top: left or right? Try clasping your hands with the other thumb on top. Note which way feels more natural. Report your personal preference ▣ On a chart, check off if you had your left thumb or right thumb on top ▣ Do you have a widow’s peak? ▣ Do you have attached or detached earlobes? ▣ Are you right or left handed? ▣ Do you have a hitchhiker’s thumb? ▣ Check it off in your chart if you do What type of variation did these characteristics display? discrete or continuous? Variation and the Environment ▣ Variation may be seen in an organism (eg: different hair colours), but sometimes it is unseen (eg: people have different blood types.)  DO 2.1 Review #1-5 - page 18 Topic 2.1 Asexual and Sexual Variation Reproduction 2.2  Asexual Reproduction Asexual Reproduction ▣ Involves only one parent ▣ Offspring are identical to the parent ▣ 4 types: 1. Binary Fission ▣ A one celled organism splits exactly into two, producing two identical individuals. ▣ It can only happen in single celled organisms such as bacteria, amoeba, and some algae. 2. Budding ▣ The parent produces a small bud or smaller version of themselves. ▣ It detaches and develops into a new but identical individual. □ Examples: yeast, hydra, coral 3. Spore Production ▣ The cells of a parent divide and make spores (similar to seeds) each of which will develop into a new individual, identical to the parent □ Fungi, green algae, some moulds, ferns and other nonflowering plants. ▣ Spores can survive in unsuitable growing conditions because they can remain dormant. 4. Vegetative Reproduction ▣ Reproduction by plants that doesn’t involve the formation of a seed □ Ex: cuttings from a plant, runners (strawberries), tubers (potatoes), bulbs (tulips), shoots or suckers (aspen)  Sexual Reproduction in Animals  How important is it that species be able to pass their characteristics on to future generations? Why? Sexual Reproduction ▣ Requires two individuals to produce offspring ▣ Offspring produced are a genetic combination of the parents □ In other words, the children are genetically different from (a variation) both parents (mix). ▣ Most animals and flowering plants (angiosperms) use sexual reproduction. Gametes ▣ Each parent has special reproductive cells (sex cells) called gametes. ▣ Sperm cells are the male gametes and egg cells (ova) are the female gametes Sexual Reproduction in Animals 1. The union of sperm and egg is called fertilization. Sexual Reproduction in Animals 2. When the gametes join together (fertilization) and a new individual grows from a fertilized cell it is called the zygote. Sexual Reproduction in Animals 3. The zygote then splits into 2 cells and then 2 more and then 2 more until a 16-cell morula is formed. This process is called cleavage. Sexual Reproduction in Animals 4. Then a multi-celled embryo develops. Embryo  Sexual Reproduction in Plants Pistil ▣ The Pistil is the female part of a flower. 1. Stigma is the sticky tip of a pistil. 2. Style is the tube connect the stigma and ovary. 3. Ovary is a tiny chamber containing the plants ovules (eggs) Stamen ▣ The Stamen is the male part of a flower. 1. Filament is the stalk of a stamen. 2. Anther is the tip of the stamen. Label: Stigma Pistil Style Anther Ovary Stamen Filament Sepal Ovule Petal Pollination ▣ Pollination is the process by which pollen, containing sperm, travels from the anther or the stamen to the stigma of the female pistil. ○ pollination is assisted by pollinator species such as bees, butterflies, and hummingbirds Cross-pollination Pollination is when the eggs of one plant are fertilized by the sperm from another plant of the same species. Pollination ▣ Self-pollination is when the sperm fertilizes the eggs in the same plant Pollination ▣ Artificial pollination can also be used to breed different varieties of plants for specific purposes.  Fill in the Chart identifying advantages and disadvantages of asexual and sexual reproduction on page 23 - you may work in partners - you may research Avantages Asexual Sexual the population can produces genetic increase rapidly when variation in the offspring the conditions are which gives them a favourable survival advantage only one parent is a disease is less likely to needed affect all the individuals it is more time and in a population energy efficient as you don't need a mate it is faster than sexual reproduction Disadvantages Asexual Sexual it does not lead to time and energy are genetic variation in a needed to find a mate population it is not possible for an the species may only be isolated individual to suited to one habitat reproduce disease may affect all gestation takes longer the individuals in a population  DO Topic 2 Review #1-15 - page 24-26