1 / 13

Biology helps us with…

Biology helps us with…. Healthy food Exercise Disease Environment Living Things. Living Things are organized from…. Cells Tissue Organs Systems Organism. Characteristics of Living Things. Organized cells, tissues, etc Respond to stimuli Maintain health – homeostasis

miracle
Download Presentation

Biology helps us with…

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Biology helps us with… • Healthy food • Exercise • Disease • Environment • Living Things

  2. Living Things are organized from… • Cells • Tissue • Organs • Systems • Organism

  3. Characteristics of Living Things • Organized cells, tissues, etc • Respond to stimuli • Maintain health – homeostasis • Use energy – metabolism • Grow and develop • Reproduce

  4. Scientific Method 1.Observation – question • Hypothesis – TESTABLE answer, may become theory if confirmed repeatedly. If_____, then ____. If = independent variable then = dependent variable 3. Experiment–control group to compare to - experimental group w/ indep var YOU choose to test 4. Conclusion – results you SEE - dependent variable

  5. MicroscopesPg 24 • Compound Light Microscope in class, more later • Scanning Electron Microscope scans surface of specimen • Transmission Electron Microscope electrons pass through specimen to show internal structures

  6. Metric SystemPage 23 and Handout

  7. Chapter 2Page 31 • Matter = mass • Elements = one kind of atom • Nucleus of atom– protons, “+”, = atomic # - neutrons, neutral - n + p = mass number • Electrons– orbit around nucleus, negative • Isotopes – same element, different mass/neutrons, radioactive, Carbon-14 • Why is mass number an average?

  8. Atom – simplest part of element • Molecule – simplest part of compound • Compound – different elements • Molecule – can be same element ex. Diatomic – H2,O2,N2, column 7 • Ionic bond – transfers electrons, makes charged elements (ions) ex. Na+1Cl-1 • Covalent bond – shares electrons, makes molecules, ex. water, carbon (4 bonds, common)

  9. Chemical Reactions • reactants  products • Activation energy – needed to start reactions • w/ catalysts like enzymes, reactions go fast/don’t need as much energy Pg 37** • Redox reactions – one element gains electron (reduction in ox #), other loses electron (oxidation) 2Mg + O2 2Mg+2O-2

  10. Acids • H2CO3, H3PO4, H2SO4, HCl • Dissociate H+ ions to form hydronium H3O+ • pH below 7 • pH “0” = strongest acid

  11. Bases • NaOH, CaOH, MgOH • Dissociate OH-- ions (hydroxide) • pH above 7 • pH 14 = strongest base • Just as corrosive as acid • Used as cleaners

  12. pH • Each # is 10 x stronger than previous # • Can’t be drawn to scale

  13. Buffers • Body uses to keep pH neutral, homeostasis • If pH above 7, H2CO3 dissociates to release H+ ions and lower pH back to 7 • If pH below 7, too many free H+ ions, HCO3 picks up H+ ions and raises pH to 7

More Related