BSC 109 Exam 4 Study Guide This study guide is to aid you in studying the course material for the exam The study guide does not replace lecture material or reading the text The topics listed below is a non exhaustive list of the main points in each chapter All material presented in lecture and the text is fair game for the exam Genetics phenotype Define the following terms chromosome gene alleles homozygous heterozygous genotype Chromosome Structures within the nucleus composed of DNA and protein Gene DNA sequences that contain instructions for building proteins located on chromosome Allele Alternative form of a gene arise from mutation many alleles are genes that do not produce a protein Homozygous two identical alleles at a particular locus Heterozygous two different alleles at a particular location Genotype an individual s complete set of alleles Tt HHtt Ww Phenotype observable physical and functional traits eye color skin color Summarize Mendel s laws of segregation and independent assortment Law of Segregation Mitosis Meiosis each individual contains 1 allele from each parent gametes carry only one allele of each gene monohybrid crosses each allele is either dominant or recessive to another allele exceptions incomplete dominance and codominance Law of Independent Assortment Meisosis Dihybird Crosses genes for different traits are separated from each other independently during meiosis when comparing two non related genes those genes do not interfere with each other as gametes only partially correct if two alleles are on the same chromosome they do not assort independently Compare and contrast incomplete dominance and codominance Incomplete Dominance three phenotypes instead of two ex Flower color red pink white ex Hair shape straight wavy curly heterozygote expresses a new phenotype Codominance both alleles are expressed ex Flower color red red and white white Describe what is meant by polygenic inheritance Polygenic Inheritance Inheritance of phenotypic traits that depend on many genes ex Skin color depends on melanocytes melanin blood comp etc ex Height body size and shape both environmental factors and genotype affect the phenotype Discuss why most sex linked traits are actually X linked rather than Y linked Males XY determine the gender of offspring Females XX More males than females express the disease Passed to sons by mother Father cannot pass the gene to sons but daughters will be carriers ex Red green color blindness hemophilia Duchenne muscular dystrophy Discuss why genes may influence general patterns of behavior but do not cause specific Genes code for proteins not for specific behaviors individual behaviors hormones enzymes structural neurotransmitters Protein functions irregularities can influence behaviors Ch 13 Endocrine System Know the functions of the endocrine system and basic terminology bold words Endocrine System collection of specialized cells and tissues that secrete hormones Endocrine glands ductless organs that secrete hormones into blood Paracrine glands tissue that secretes hormones into the surrounding tissues and cells ex neurotransmitters FUNCTIONS Homeostasis regulation of chemicals in the body Endocrine organs release hormones that regulate all major systems of your body ex Mood sleep cycles energy heart rate etc Synthesize Hormones production of all hormones Endocrine organs tissues build hormones before releasing them only certain organs synthesize specific hormones Monitor blood for hormone level Endocrine glands tissues detect hormone levels respond by increasing or decreasing productions negative feedback loop act as a thermostat for all major chemical balances Hormones Chemical produced secreted by an endocrine gland that causes an effect on a different organ tissue circulate in the blood stream functions as fast communication between organs that are not close in proximity increased concentration increase gland size and vice versa Distinguish between steroidal and nonsteroidal hormones based upon their method of action on their target cells Steroid Hormones Bypass cell membrane binds inside the cell structurally related to cholesterol lipid soluble enter target cells bind to intracellular receptor sometimes on the nucleus activate specific genes to produce specific proteins slower acting than nonsteroid hormones minutes to hours activates DNA to create new protein enzyme Nonsteroid Hormones Binds to receptors on target cell membranes binds outside the cell structurally related to proteins water soluble lipid insoluble work through intermediate mechanisms to activate existing enzymes may involve a second messenger within the cell such as cyclic AMP cAMP faster action than steroid hormones seconds to minutes activates enzymes already built Define negative feedback and positive feedback of hormones to maintain homeostasis Negative Feedback Shut off production counters stimulus endocrine gland serves as the control center hormone is the pathway between the control center and the effectors target tissues or organs are the effectors operates just as a thermostat in a house controls the temperature Positive Feedback End product increases initial production increased production of hormones will increase further production of hormones creates a loop where the final product of the hormone increases the production of the initial hormone eventually creates a negative feedback loop to shut off hormone Know the hormones where they are produced what they target and their effects for all endocrine organs Posterior pituitary hormones nonsteroidal Antidiuretic hormone ADH conserves water in kidneys regulates water balance in body AKA Vasopressin Oxytocin causes uterine contractions during labor and milk ejection through neuroendocrine reflex Anterior pituitary hormones ACTH adrenocorticotropic hormone stimulates adrenal cortex to release glucocorticoids cortisol TSH thyroid stimulating hormone acts on thyroid gland promoting release of thyroid hormones FSH and LH gonadotropins stimulate growth development and function of ovaries and testes not produced until about age 10 13 puberty increase in production initiates sexual maturation and development at puberty Prolactin Growth hormone stimulates development of mammary glands and milk production has widespread effects on body major effects on bone muscle most of its growth promoting effects occur during childhood and adolescence Pancreas hormones Glucagon raises blood sugar causes breakdown of glycogen to