Download presentation
Presentation is loading. Please wait.
Published byJoseph Sims Modified over 9 years ago
1
2-1 Characteristics of Living Things
2
1.Made of one or more units called cells
3
2. Reproduce
4
3. Grow and Develop
5
4.Obtain and use energy
6
5. Respond to their environment
7
#1 Living things are made up of cells Cell – small self contained unit Can perform all the functions of life Cell – small self contained unit Can perform all the functions of life
8
Unicellular – organism made of one cell Multicellular – organism made of many cells Unicellular – organism made of one cell Multicellular – organism made of many cells
9
Cells are only found in living material or material that was once alive
10
#2 Living things Reproduce Produce organisms like themselves
11
Sexual reproduction – 2 cells formed from different individuals unite to form an organism
12
Asexual Reproduction – single
13
#3 – Living things grow and develop Are capable of growth at one stage of their life cycle at least Development – cycle of growth Are capable of growth at one stage of their life cycle at least Development – cycle of growth
14
Aging – comes at the end of development –Organism becomes less efficient at the process of life Aging – comes at the end of development –Organism becomes less efficient at the process of life
15
#4 – Living things obtain and use energy Energy from their environment or surroundings Energy to grow, develop, and reproduce Energy from their environment or surroundings Energy to grow, develop, and reproduce
16
Metabolism = Anabolism + Catabolism
17
Anabolism – putting together or synthesizing complex substances from simpler substances
18
Plants – photosynthesis Animals – take in energy food Plants – photosynthesis Animals – take in energy food
19
Catabolism – final breakdown of complex substances into simpler substances resulting in the release of energy
20
#5 – Living Things respond to their environment Slow – changes in metabolic processes Rapid – changes in behavior Slow – changes in metabolic processes Rapid – changes in behavior
21
Stimulus – anything that causes an organism to react Irritability – the ability of living things to react to stimuli Stimulus – anything that causes an organism to react Irritability – the ability of living things to react to stimuli
22
Living things respond to stimuli in a way that improves their chances for survival
23
Homeostasis Organisms ability to maintain constant or stable conditions that are necessary for life Process by which organisms respond to different stimuli Homeo – same Stasis – stopping/standing Organisms ability to maintain constant or stable conditions that are necessary for life Process by which organisms respond to different stimuli Homeo – same Stasis – stopping/standing
25
2-2 Biology: The Study of Life
26
Biology – the study of life Biologist – person who studies living things Biology – the study of life Biologist – person who studies living things
27
Branches of Biology Many divisions –Molecular biologist –Cell biologist –Zoologist (animals) –Botanist (plants) –Paleontologists –Ecologists –Global Ecologists Many divisions –Molecular biologist –Cell biologist –Zoologist (animals) –Botanist (plants) –Paleontologists –Ecologists –Global Ecologists
29
Questions at the …. Molecular level Cellular level Multicellular level Population level Global level Molecular level Cellular level Multicellular level Population level Global level
30
Tools of a Biologist
32
To study small organisms microscopes –Produces a larger image To study small organisms microscopes –Produces a larger image
33
Compound Light Microscope Most common Can observe living organisms Light passes through the organism Two types of lenses – Objectives – 2 –Ocular (eyepiece) Most common Can observe living organisms Light passes through the organism Two types of lenses – Objectives – 2 –Ocular (eyepiece)
34
Total Magnification = Ocular x Objective Total Magnification = Ocular x Objective
36
Limit of Resolution Beyond this point objects become blurry and detail is lost – will always exist Increase magnification – more and more detail until you reach the limit of resolution Beyond this point objects become blurry and detail is lost – will always exist Increase magnification – more and more detail until you reach the limit of resolution
38
Staining Colors some parts of the cell to make them clearly visible
40
Types of Microscopes Compound light microscope Electron microscope Compound light microscope Electron microscope
41
Electron Microscope
42
Can see smaller things than the compound Uses electromagnets to bend electrons Two types – SEM and TEM Can see smaller things than the compound Uses electromagnets to bend electrons Two types – SEM and TEM
43
TEM (Transmission) How it works – shine a beam of electrons at a sample and magnify the image onto a florescent screen (TV)
44
SEM – Scanning How it works – beam of electrons scans back and forth across the surface of a specimen Electrons bounce off the specimen are picked up by detectors and a 3-D image is formed How it works – beam of electrons scans back and forth across the surface of a specimen Electrons bounce off the specimen are picked up by detectors and a 3-D image is formed
47
Limitations of Electron Microscopes Specimens must be in a vacuum (no air) Thin slices Stained, dried out or dead Specimens must be in a vacuum (no air) Thin slices Stained, dried out or dead
48
Laboratory Techniques of a Biologist
49
Centrifugation Cell fractionation – cells blended in a blender Broken bits spun 20,000x a minute Cell fractionation – cells blended in a blender Broken bits spun 20,000x a minute
51
Heaviest parts sink Scientists remove the part they want Heaviest parts sink Scientists remove the part they want
52
Micromanipulation Microdissection – can be used to remove cell parts Can be used to insert material in a living cell Microdissection – can be used to remove cell parts Can be used to insert material in a living cell
53
Cell Cultures Used to produce large numbers of cells Cell is grown in a dish with nutrients Overtime many cells develop Used to produce large numbers of cells Cell is grown in a dish with nutrients Overtime many cells develop
54
The End
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.