How do we classify something as living?

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How do we classify something as living?

• Living things
• 1. Have a need for energy
• (from chemicals, sunlight, other animals, etc.)
• 2. Respond to their environment (to survive)
• 3. Have the ability to reproduce pass genetic
  info
• (asexual or sexual)
• 4. Are made up of one or more cells

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Cell Theory

• 3 basic components
• All organisms are made of cell(s).
• All existing cells are produced by other living
  cells.
• The cell is the most basic unit of life.

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2 Types of Cells

• 1. Prokaryotes No nucleus (before nucleus)
• Bacteria

(Kingdom Monera)
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• 2. Eukaryotes Nucleus (true nucleus)
• All other Kingdoms
• Fungi
• Plants
• Protists
• Animals
• Eukaryotic cells have many organelles- Structures
  that perform specific functions.
• plasma membrane, cytoplasm, nucleus

(Kingdom Fungi)
(Kingdom Plantae)
(Kingdom Protista)
(Kingdom Animalia)
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Cell Locomotion

• Cilia eyelashes
• Flagella small whips
• Locomotion needed to find a food source or
  escape predators/harsh conditions.

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Tools for Viewing Life

• Light Microscope
• Compound
• Stereo/ Dissecting
• Electron Microscope
• Scanning (SEM)
• Transmission (TEM)
• X-rays
• Ultrasound
• MRI Magnetic resonance imaging

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Light Microscopes

• Compound 1 optical system
• Magnification Up to 1500x (LGHS400x)
• (objective x eyepiece)
• Images Upside down and reversed

http//ettc.lrhsd.org/archives/Pictures/138-micros
copes-lg.jpg
http//www.az-microscope.on.ca/images/Ml2100.jpg
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• Stereo 2 separate optical systems
• (for objects that will not fit on a slide)
• Magnification Up to 100x (LGHS 40x)
• Images 3D, normal upright, right to left image

http//www.microscopyu.com/articles/stereomicrosco
py/stereointro.html
http//www.clt.astate.edu/mhuss/stereoparts.jpg
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Electron Microscopes

• Scanning (SEM)
• Uses electrons instead of light to form/focus
  image
• Used to view surfaces of objects
• (electrons deflect off specimens)
• Magnification up to 500,000x

Fly Head
http//image53.webshots.com/53/8/76/41/24848764100
85329142tuvzFM_fs.jpg
http//gsc.nrcan.gc.ca/labs/ebeam/images/sem8.jpg
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• Transmission (TEM)
• Uses electrons instead of light to form/focus
  image
• Used to view inner structure of objects
• (electrons pass through specimens)
• Magnification up to 1, 000,000x

TEM-micrograph thylakoid system in a chloroplast
(bar 0.5 µm).
http//www.iopb.res.in/bhupen/tem_mch.gif
http//images.google.com/imgres?imgurlhttp//www-
classic.uni-graz.at/pphwww/elmi/tem2.jpgimgrefurl
http//www-classic.uni-graz.at/pphwww/elmi/tempra
eparatione.htmusg__a3m7XGYsX7CRKvKD0cd0qlD36jk
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TEM vs. SEM
http//www.vcbio.science.ru.nl/images/TEM-SEM-elec
tron-beam.jpg
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X-Ray

• X-rays (a type of light wave) pass through tissue
  to show dense material (which absorbs the rays)
• CT- scans also use this technique

http//www.designswan.com/wp-content/uploads/2008/
xray/22.jpg
http//www.antonine-education.co.uk/physics_gcse/U
nit_1/Topic_5/em_spectrum.jpg
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Ultrasound

• High-frequency sound waves pass through the body
  until they come to a border between two tissues
  that conduct sound differently. Then, some of
  the sound waves bounce back are produced as a
  picture.
• When used for long periods of time at high
  intensities, it can cause the tissues to become
  heated. 

http//www.nlm.nih.gov/medlineplus/ency/images/enc
y/fullsize/18056.jpg
http//www.hip2b2.com/images/uploaded_images/Ultra
sound.jpg
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MRI

• Uses a magnetic field and radio waves to create
  detailed images of body tissues.
• Can take images from almost every angle

http//i.ehow.com/images/GlobalPhoto/Articles/4673
792/92555-main_Full.jpg
http//www.magnet.fsu.edu/education/tutorials/magn
etacademy/mri/images/mri-scanner.jpg