Philosophy of biology

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ANNALS OF HUMAN BIOLOGY, 1978, VOL. 5, NO. 5, 487--489 Natural selection and birthweight N. BLURTON JONES Department of Growth and Development, Institute of Child Health, University of London [Received 23 March 1978; revised 6 May 1978] Summary. Mean birthweight, even before induced births became commonplace, is slightly lower than the birthweight at which peri- natal mortality is lowest. This finding, once hard to explain by natural selection, is shown to be exactly in line with predictions from natural selection theory. 1. Introduction Karn and Penrose (1952) showed that mean birthweight in man was slightly lower than the "optimum" birthweight, defined as the weight at which perinatal

Ch. 55 Campbell's AP Bio

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Environment

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ch. 55

ap bio

campbell's

outline

Chapter 55 Conservation Biology and Restoration Ecology Lecture Outline Overview: The Biodiversity Crisis Conservation biology integrates ecology, evolutionary biology, physiology, molecular biology, genetics, and behavioral ecology to conserve biological diversity at all levels. Restoration ecology applies ecological principles in an effort to return degraded ecosystems to conditions as similar as possible to their natural, predegraded state. Scientists have described and formally named about 1.8 million species of organisms. Some biologists think that about 10 million more species currently exist. Others estimate the number to be as high as 200 million.

AP Bio hardy Weinberg lab

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Population genetics

Genetics

Statistical genetics

Hardy–Weinberg principle

Evolution

Introduction to evolution

Heredity

Social Issues

BigIdea Investigation 2 S25 Evolution 1 INVESTIGATION 2 MATHEMATICAL MODELING: HARDY-WEINBERG* How can mathematical models be used to investigate the relationship between allele frequencies in populations of organisms and evolutionary change? ? BACKGROUND Evolution occurs in populations of organisms and involves variation in the population, heredity, and di!erential survival. One way to study evolution is to study how the frequency of alleles in a population changes from generation to generation. In other words, you can ask What are the inheritance patterns of alleles, not just from two parental organisms, but also in a population? You can then explore how allele frequencies change in populations and how these changes might predict what will happen to a population in

Ap Bio Chapter 24

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Species

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AP Biology Reading Guide Chapter 24: The Origin of Species Fred and Theresa Holtzclaw Copyright ? 2010 Pearson Education, Inc. - 1 - Name _______________________ Period ___________ Chapter 24: The Origin of Species Overview 1. What was Darwin?s ?mystery of mysteries?? 2. Define speciation. 3. Distinguish between microevolution and macroevolution. Concept 24.1 The biological species concept emphasizes reproductive isolation 4. Use the biological species concept to define species. 5. What is required for the formation of new species? 6. What are hybrids? 7. Explain the two types of barriers that maintain reproductive isolation.

Ap bio chapter 23 outline notes

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Population genetics

Hardy–Weinberg principle

CHAPTER 23 THE EVOLUTION OF POPULATIONS OUTLINE I. Population Genetics A. The modern evolutionary synthesis integrated Darwinian selection and Mendelian inheritance B. The genetic structure of a population is defined by its allele and genotype frequencies C. The Hardy-Weinberg theorem describes a nonevolving population II. Causes of Microevolution A. Microevolution is a generation-to-generation change in a population's allele or genotype frequencies B. The five causes of microevolution are genetic drift, gene flow, mutation, nonrandom mating, and natural selection III. Genetic Variation, the Substrate for Natural Selection A. Genetic variation occurs within and between populations B. Mutation and sexual recombination generate genetic variation

AP bio chapter 24 outline notes

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Speciation

Scientific classification

Allopatric speciation

Sympatry

Reproductive isolation

Species problem

On the Origin of Species

Species

Environment

CHAPTF,F.24 THE ORIGIN OF SPECIES OUTLII\E L What Is a SPecies? A. The biological species concept emphasizes reproductive isolation B. prezygotic and postzygotic barriers isolate the gene pools of biological species C. The biological species concept does not work in all situations D. Other species concepts emphasize features and processes that identiff and unite species members II. Modes of SPeciation A. Geographical isolation can lead to the origin of species: allopatric speciation B. A new species can originate in the geographical midst of the parent species: sympatric sPeciation c. Genetic change in populations can account for speciation D. The punctuated equilibrium model has stimulated research on the tempo of speciation The Origin of Evolutionary NoveltY

Bio Notes Genetics

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Genetics

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Sex Linked genes -The X and Y chromosomes determine the sex of an individual and contain genes related to female and maleness. All other genes on these chromosomes are called sex linked genes -The X chromosome has the most genes but in some species (fruit fly), genes are found on the Y chromosome as well. genes on the Y chromosome are only passed from father to son -Sex linked gene inheritance (x linked) can be studied using fruit flies. The gene for eye color is located on the X chromosome. R-Red eyes are dominant to r white eyes. -Alleles carried on the X chromosome are shown as X^R, and X^r, Females have 2 alleles (X^R X^R, X^R X^r, or X^r X^r) while males only have one (X^R Y, or X^r Y) The male?s phenotype results from one X allele plll. Sex Linked Disorders In Humans

Chapter 50 Lecture

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Outline of ecology

Environment

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biology ppt lecture

Chapter 50 Lecture Intro to Ecology CHAPTER 50 AN INTRODUCTION TO ECOLOGY AND THE BIOSPERE Copyright ? 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section A: The Scope of Ecology 1. The interaction between organisms and their environments determine the distribution and abundance of organisms 2. Ecology and evolutionary biology are closely related sciences 3. Ecological research ranges from the adaptations of individual organisms to the dynamics of the biosphere 4. Ecology provides a scientific context for evaluating environmental issues Ecology is the scientific study of the interactions between organisms and their environment. Introduction Copyright ? 2002 Pearson Education, Inc., publishing as Benjamin Cummings

AP Biology Chapter 19

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Developmental biology

Cell biology