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Genetic Recombination in Eukaryotes: Meiosis

Sexual reproduction: production of offspring; union of male and female gametes Gametes: eggs and sperms cells in animals Sexual reproduction depends on Meiosis; specialized process of cell division; recombines DNA sequences, produces cells with half the number of chromosomes in somatic cells. (chromosome= reduction) Fertilization: nuclei of egg/ sperm fuse; producing zygote (# chromosomes typical…

Prokaryotic: F factor, Transformation, Transduction

Genetic recombination needs: Homologous chromosomes; must differ from one another along one at least two spots Mechanism to bring into close proximity of each other Homology allows the DNA to line and recombine precisely. Cut and passing 4 DNA backbones results in 1 recombination event. Lederberg Experiment E.coli grown in minimal medium; contains water, organic…

Cell Cycles: Interphase, Mitosis, Cytokinesis

Cell Cycle: nuclear division, cytokinesis Parental cell: genetic copies of parental cell 3 process: checks/ regulators for each step to ensure timely progression, replication process to synthesis DNA into two copies, interwoven “cables” and “motors” of mitotic cytoskeletons. Chromosomes: nuclear units of genetic information; DNA molecules combined with proteins. In eukaryotes, heredity information of nucleus…

Sexual Motivation: The Physiology of Sex

Sexual response cycle – four stage cycle experienced during sexual arousal Excitement phase – arousal builds rapidly Plateau phase – respiration, heart rate, vasocongestion, and muscle tension continue to build until there is enough muscle tension to trigger orgasm Orgasm phase – males: rhythmic contractions of internal organs and muscle tissue surrounding the urethra project…

Types of Motivation and Emotion

Motivation – process that influences the direction, persistence, and vigour of goal directed behaviour Perspectives on Motivation Instinct Theory and Modern Evolutionary Psychology Instinct (fixed action pattern) – an inherited characteristic, common to all members of a species, that automatically produces a particular response when the organism is exposed to a particular stimulus Theories faded…

Hunger & Weight Regulation: The Physiology of Hunger

Metabolism – body’s rate of energy utilization Two-thirds of energy used goes to support basal metabolism, the resting, continuous metabolic work of body cells Immediate energy supply information interacts with other signals to regulate food intake (hunger not necessarily linked to immediate energy needs) Homeostatic mechanisms are designed to prevent people from running low on…

Types of Reasoning & Stages of Problem Solving

Two types of reasoning: Deductive reasoning – reasoning from a general principle to a specific case Basis of formal mathematics and logic Viewed as stronger and more valid reasoning because conclusion cannot be false if premises are true Syllogism: If all humans are mortal (first premise), and Socrates is a human (second premise), then Socrates…

Language: History and Structure

Language: History and Structure Language – a system of symbols and rules for combining these symbols in ways that can produce an almost infinite number of possible messages and meanings Three critical properties of language: Symbolic: Uses sounds, written signs, or gestures to refer to objects, events, ideas, and feelings Displacement – capacity of language…