Two main sources of genetic variation
... 2. Stabilizing Selection • Eliminates extreme expressions of a trait when the average expression leads to higher fitness. • Most common form of natural selection. ...
... 2. Stabilizing Selection • Eliminates extreme expressions of a trait when the average expression leads to higher fitness. • Most common form of natural selection. ...
Slide 1 - Dr. Tricia Britton
... 2) Adaptation happens through natural selection. The event that causes isolation may also change the environment. The separated populations must adapt to their environments. Each population will have different adaptations. 3) Differentiation ...
... 2) Adaptation happens through natural selection. The event that causes isolation may also change the environment. The separated populations must adapt to their environments. Each population will have different adaptations. 3) Differentiation ...
Evolution and Natural Selection
... Results in 4 haploid gametes each with a unique set of DNA which produce further variation through sexual reproduction and fertilisation ...
... Results in 4 haploid gametes each with a unique set of DNA which produce further variation through sexual reproduction and fertilisation ...
Exam 5 Review - Iowa State University
... 1. Amish people of Lancaster County, Pennsylvania. They are descended from a few dozen individuals belonging to an Anabaptist sect in Germany who migrated to Pennsylvania during the early 1700's. Over the last 40 years of the 20th century, 61 babies with an extremely rare fatal genetic disorder know ...
... 1. Amish people of Lancaster County, Pennsylvania. They are descended from a few dozen individuals belonging to an Anabaptist sect in Germany who migrated to Pennsylvania during the early 1700's. Over the last 40 years of the 20th century, 61 babies with an extremely rare fatal genetic disorder know ...
Biology Test: Chapter 6 Introduction to Genetics 1. _____ What type
... _____ Crossing different true-breeding(purebred) stocks produces offspring called a. P generation b. F2 generation ...
... _____ Crossing different true-breeding(purebred) stocks produces offspring called a. P generation b. F2 generation ...
Intro to Darwin and Biodiversity
... Species diversity is the variety of species that exist on Earth. In an ecosystem, each species (plants, animals, unicellular organisms) are important for the health and survival of the whole ecosystem. The more species that live in an ecosystem, the better for that ecosystem. ...
... Species diversity is the variety of species that exist on Earth. In an ecosystem, each species (plants, animals, unicellular organisms) are important for the health and survival of the whole ecosystem. The more species that live in an ecosystem, the better for that ecosystem. ...
Oral Presentations - Human Reproduction
... years, it has lost 1393 of its original 1438 genes, and at this rate it will lose the last 45 in a mere 10 million years. If you don’t believe this can happen, ask the mole vole, whose Y has completely disappeared. But – maybe rescue is at hand. In self-defence, the Y seems to be able to make more c ...
... years, it has lost 1393 of its original 1438 genes, and at this rate it will lose the last 45 in a mere 10 million years. If you don’t believe this can happen, ask the mole vole, whose Y has completely disappeared. But – maybe rescue is at hand. In self-defence, the Y seems to be able to make more c ...
17) Limitations of the Biological Species Concept
... • An!allopolyploid!is!a!species!with!multiple!sets!of! chromosomes!derived!from!different species – While!a!hybrid!is!often!sterile,!as!is!the!one!below!with!7! chromosomes,!it!may!be!able!to!reproduce!asexually – The!new!species!has!a!diploid!#!=!7+3!=!10,!a!number!that!now!can! make!gametes!with!a ...
... • An!allopolyploid!is!a!species!with!multiple!sets!of! chromosomes!derived!from!different species – While!a!hybrid!is!often!sterile,!as!is!the!one!below!with!7! chromosomes,!it!may!be!able!to!reproduce!asexually – The!new!species!has!a!diploid!#!=!7+3!=!10,!a!number!that!now!can! make!gametes!with!a ...
Hybrid Oaks: Full of Vexation and Wonder
... terbreeding or, more subtly, to minimize gene flow between them even if occasional hybrids do form. These biological factors have come to be known as reproductive isolating mechanisms. These isolating mechanisms are credited with great theoretical significance because, in the absence of genetic isol ...
... terbreeding or, more subtly, to minimize gene flow between them even if occasional hybrids do form. These biological factors have come to be known as reproductive isolating mechanisms. These isolating mechanisms are credited with great theoretical significance because, in the absence of genetic isol ...
The Origin and Diversification of Life on Earth
... – Natural selection can only refine a structure in the context of its current utility, it does not predict future change. – In birds, did feathers or lightweight bones come first? The first flights may have been glides or extended hops. Feathers are also used for warmth. ...
... – Natural selection can only refine a structure in the context of its current utility, it does not predict future change. – In birds, did feathers or lightweight bones come first? The first flights may have been glides or extended hops. Feathers are also used for warmth. ...
Variation in Plants
... individuals. This is called outcrossing. • Outcrossing is often obligatory. This may occur because of self-incompatibility. Nonsynchronous release of pollen and receptive stigmas is another common mechanism. ...
... individuals. This is called outcrossing. • Outcrossing is often obligatory. This may occur because of self-incompatibility. Nonsynchronous release of pollen and receptive stigmas is another common mechanism. ...
Evolution Unit Test Review
... • B) Antarctica and South Africa separated after Thrinaxodon went extinct • C) fossils found in a given area look like the modern species in that same area • D) the environment where it lived was very warm ...
... • B) Antarctica and South Africa separated after Thrinaxodon went extinct • C) fossils found in a given area look like the modern species in that same area • D) the environment where it lived was very warm ...
evolution 2 - Hicksville Public Schools
... The least genetic variation will probably be found in the offspring of organisms that reproduce using (1) mitosis to produce a larger population (2) meiosis to produce gametes (3) fusion of eggs and sperm to produce zygotes (4) internal fertilization to produce an embryo ...
... The least genetic variation will probably be found in the offspring of organisms that reproduce using (1) mitosis to produce a larger population (2) meiosis to produce gametes (3) fusion of eggs and sperm to produce zygotes (4) internal fertilization to produce an embryo ...
Slide 1
... happens over a relatively short period of time. Most scientists agree that natural selection, acting over very long periods of time, leads to speciation. (“Adding branches to the tree.”) There are two patterns of evolution described by scientists based on observations of living and ...
... happens over a relatively short period of time. Most scientists agree that natural selection, acting over very long periods of time, leads to speciation. (“Adding branches to the tree.”) There are two patterns of evolution described by scientists based on observations of living and ...
Mechanisms of Evolution
... Mechanisms of Evolution a. Species: a group of organisms that can interbreed and produce fertile offspring b. Population: a group of interbreeding species occupying a particular area c. Evolution is simply a change in the frequency of genes in a population. Evolution occurs by Natural Selection. Nat ...
... Mechanisms of Evolution a. Species: a group of organisms that can interbreed and produce fertile offspring b. Population: a group of interbreeding species occupying a particular area c. Evolution is simply a change in the frequency of genes in a population. Evolution occurs by Natural Selection. Nat ...
Document
... same range -- but they have different microhabitat preferences and so hybridization is rare. ...
... same range -- but they have different microhabitat preferences and so hybridization is rare. ...
The Origin of Species
... unique structural features • Phylogenetic species concept - emphasis is on ancestor-descendent relationships • Pluralistic species concept - acknowledges that, where species concepts are concerned, one size may not fit all! ...
... unique structural features • Phylogenetic species concept - emphasis is on ancestor-descendent relationships • Pluralistic species concept - acknowledges that, where species concepts are concerned, one size may not fit all! ...
Biology of Plants
... • three kingdoms – Animal phyla (protozoa) – Plant divisions – Protista (eukaryotic cells not animal or plant) ...
... • three kingdoms – Animal phyla (protozoa) – Plant divisions – Protista (eukaryotic cells not animal or plant) ...
Classification of All Living Things
... This is the Genus and Species of an organism This two part system is called binomial nomenclature Remember the rules Capitalize the genus Lower case species Underline or italics both Use Latin terms to describe ...
... This is the Genus and Species of an organism This two part system is called binomial nomenclature Remember the rules Capitalize the genus Lower case species Underline or italics both Use Latin terms to describe ...
slides - Botany
... Autopolyploidy: “self” duplication – whole genome duplication within single species Allopolyploidy: “other” duplication – whole genome duplication combined with hybridization of two species The distinction can be unclear ...
... Autopolyploidy: “self” duplication – whole genome duplication within single species Allopolyploidy: “other” duplication – whole genome duplication combined with hybridization of two species The distinction can be unclear ...
D. dominant trait
... Some species like mosses and sponges can reproduce either asexually or sexually. Some species, such as jellyfish, can alternate how they reproduce and so one generation may reproduce sexually while the next reproduces asexually. 27. An advantage of sexual reproduction over asexual reproduction is th ...
... Some species like mosses and sponges can reproduce either asexually or sexually. Some species, such as jellyfish, can alternate how they reproduce and so one generation may reproduce sexually while the next reproduces asexually. 27. An advantage of sexual reproduction over asexual reproduction is th ...
Quiz 11 1. Which is NOT a requirement for a population to satisfy the
... what proportion of the population will have many small flowers if they mate randomly? a. 40% b. 36% c. 64% d. 16% 3. Which is NOT a requirement for evolution by natural selection? a. phenotypic differences among individuals b. genetic differences among individuals c. the population size must be larg ...
... what proportion of the population will have many small flowers if they mate randomly? a. 40% b. 36% c. 64% d. 16% 3. Which is NOT a requirement for evolution by natural selection? a. phenotypic differences among individuals b. genetic differences among individuals c. the population size must be larg ...
Notes-Overall Summary - Boone County Schools
... Heredity-passing of traits from parents to offspring Genetics-the study of how traits are passed Gene-basic unit of inheritance, passed from parents to offspring, determines traits Trait-characteristic or feature of an organism (eye color) DNA-chemical in nucleus that contains the code tha ...
... Heredity-passing of traits from parents to offspring Genetics-the study of how traits are passed Gene-basic unit of inheritance, passed from parents to offspring, determines traits Trait-characteristic or feature of an organism (eye color) DNA-chemical in nucleus that contains the code tha ...
Changes Over Time
... male donkey and a female horse The term "mule" (Latin mulus) was formerly applied to the infertile offspring of any two creatures of different species. • The chromosome match-up more often occurs when the jack (male donkey) is the sire and the mare (female horse) is the dam. Sometimes people let a s ...
... male donkey and a female horse The term "mule" (Latin mulus) was formerly applied to the infertile offspring of any two creatures of different species. • The chromosome match-up more often occurs when the jack (male donkey) is the sire and the mare (female horse) is the dam. Sometimes people let a s ...
Sexual and Asexual Reproduction - UNC
... Relatively few species reproduce asexually, or in a way that does not involve male and female partners. In contrast to sexual reproducers, every organism that reproduces asexually passes on its entire set of genes to the next generation. These species have a few distinct advantages over those that m ...
... Relatively few species reproduce asexually, or in a way that does not involve male and female partners. In contrast to sexual reproducers, every organism that reproduces asexually passes on its entire set of genes to the next generation. These species have a few distinct advantages over those that m ...
Hybrid (biology)
In biology a hybrid, also known as cross breed, is the result of mixing, through sexual reproduction, two animals or plants of different breeds, varieties, species or genera. Using genetic terminology, it may be defined as follows. Hybrid generally refers to any offspring resulting from the breeding of two genetically distinct individuals, which usually will result in a high degree of heterozygosity, though hybrid and heterozygous are not, strictly speaking, synonymous. a genetic hybrid carries two different alleles of the same gene a structural hybrid results from the fusion of gametes that have differing structure in at least one chromosome, as a result of structural abnormalities a numerical hybrid results from the fusion of gametes having different haploid numbers of chromosomes a permanent hybrid is a situation where only the heterozygous genotype occurs, because all homozygous combinations are lethal.From a taxonomic perspective, hybrid refers to: Offspring resulting from the interbreeding between two animal species or plant species. See also hybrid speciation. Hybrids between different subspecies within a species (such as between the Bengal tiger and Siberian tiger) are known as intra-specific hybrids. Hybrids between different species within the same genus (such as between lions and tigers) are sometimes known as interspecific hybrids or crosses. Hybrids between different genera (such as between sheep and goats) are known as intergeneric hybrids. Extremely rare interfamilial hybrids have been known to occur (such as the guineafowl hybrids). No interordinal (between different orders) animal hybrids are known. The third type of hybrid consists of crosses between populations, breeds or cultivars within a single species. This meaning is often used in plant and animal breeding, where hybrids are commonly produced and selected, because they have desirable characteristics not found or inconsistently present in the parent individuals or populations.↑ ↑ ↑ ↑