attachment-8.ashx - Unit 1 Ch 1 Scientists tend to organize...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Unit 1: Ch. 1 Scientists tend to organize life into levels based on complexity—each simple step leads to a more complex one above it. Life —have to meet ALL requirements: 1. Composed of one or more cells 2. Respond to stimuli 3. Homeostasis 4. Acquire and use energy 5. Grow 6. Potential to reproduce 7. Evolve Classification: 1. Type of cells (prokaryotic—no nucleus, smaller/eukaryotic—nucleus, larger) 2. Number of cells (single celled—most organisms, clump together/multicellular— depend on complex communication) 3. How it obtains energy (heterotroph—other feeder/autotroph—self feeder) 3 domains: Bacteria, Archaea, Eukarya Scientific Theory: Tested repeatedly “law” or “principle” Science: systematic way to study or world; rigorous, repeatable, and falsifiable Method: observation, question, hypothesis, prediction, experiment, conclusion Ch. 14 Evolution: “descent with modification”; Microevolution : little chances; Macroevolution : build up of changes over of time History of evolutionary thought: Plato and Aristotle—organisms were randomly created and didn’t change form; arranged on a ladder increasing perfection (ladder of nature) Lyell and Hutton—earth is not 4000-6000 years old; eternal; 4.5 billion species changing over time Jean Baptiste Lamarck—acquired characteristics over time Darwin and Wallace—Origin and Species—Natural Selection 1859; how organisms change and how small changes occur; only the strong survive 1. Variation 2. Variation is heritable 3. Potential to reproduce exponentially
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
4. Traits more likely to survive than others Ch. 15 Population —set of individuals of the same species in one area Individual —contains unique set of genes Proteins —most structures and functions of an organism Prokaryotes —haploid; one copy of every gene Eukaryotes —diploid; two copies (one form mom, one from dad); if used sexual reproduction they would have haploid cells (gametes) Alleles —different; yield different proteins Gene —1 to 100 alleles Genotype —what it has in its genetic makeup Phenotype —how it is expressed (physical) Total Gene Pool —sum of all genes present in a population Gene pool for a single gene —all alleles present Allele Frequency —relative portion for each allele; ex: population of 25 hamsters (diploid) contains 50 alleles that controls coat color; 20 out of 50 alleles have code for black coats (20/50 = 0.40X100 = 40% Affects allele frequency: No gene flow No mutation Large population Mating random No natural selection Fitness —term that describes success at passing on genes to future generations; natural selection impacts fitness; better to have more fitness; means reproduction Species —a group of actually potentially unbreeding populations which are reproductively isolated from other such groups CH. 16 Understand what is meant by speciation – how a single species can have populations that are isolated from each other and diverge genetically so much that they would
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 13

attachment-8.ashx - Unit 1 Ch 1 Scientists tend to organize...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online