Introduction to Human BiologyIntroduction to Human Biology
Biological Properties of HumansBiological Properties of Humans
Scientific ProcessScientific Process
Biological InquiryBiological Inquiry
Bio = of living thingsBio = of living things
What Are the Characteristics of Humans What Are the Characteristics of Humans as Living Organisms?as Living Organisms?
How Do Biologists Study Living Things? How Do Biologists Study Living Things?
Characteristics of Living ThingsCharacteristics of Living Things
Propose as many differences as you can Propose as many differences as you can between a living organism and a non-living thing. between a living organism and a non-living thing.
fungal mycelia on a corn tortilla Gloeocapsamedicinal leech
Giardia
meerkats
cotton
Characteristics of Humans as Characteristics of Humans as Living OrganismsLiving Organisms
• Humans are highly organized Humans are highly organized – Composed of many cells = multicellularComposed of many cells = multicellular– cellscellstissuestissuesorgansorgansorgan organ
systemssystems Organic molecules = carbon-containing Organic molecules = carbon-containing
building blocks of lifebuilding blocks of life
Organizational Hierarchy Organizational Hierarchy of the Human Bodyof the Human Body
Organ SystemOrgan System
Central Nervous
System
OrganOrganBrain
TissueTissueNerve
CellCellNeuron
Smallest Unit of LifeSmallest Unit of Life
Human Cells are Highly OrganizedHuman Cells are Highly Organized
Organelle: region of cell with specialized functionOrganelle: region of cell with specialized function
Characteristics of Humans Characteristics of Humans As Living OrganismsAs Living Organisms
• Human beings acquire Human beings acquire and use materials and and use materials and energyenergy
Energy = ability to do Energy = ability to do work work
Metabolism = sum of Metabolism = sum of chemical reactions in chemical reactions in an organisman organism
Characteristics of Humans As Living OrganismsCharacteristics of Humans As Living Organisms
• Human beings reproduce, grow and developHuman beings reproduce, grow and develop
Growth = increase in sizeGrowth = increase in size
Development = change in characteristicsDevelopment = change in characteristics
Characteristics of Humans As Living Characteristics of Humans As Living OrganismsOrganisms
• Human beings use DNA reproduce Human beings use DNA reproduce themselves.themselves.
The molecule of heredity = The molecule of heredity =
DNA = DNA = ddeoxyriboeoxyribonnucleic ucleic aacidcid
Sub-Cellular Organizational Sub-Cellular Organizational Hierarchy of Life with ExamplesHierarchy of Life with Examples
sub-atomic particlessub-atomic particles
atomatom
moleculemolecule
protons, neutrons, electronsprotons, neutrons, electrons
nitrogennitrogen
nucleotidenucleotide
genegene
chromosomechromosomegenomegenome
organelleorganelle nucleusnucleus
macromoleculemacromolecule DNADNA
cellcell neuronneuron
A nucleotide molecule contains aA nucleotide molecule contains aphosphate group, sugar and base.phosphate group, sugar and base.
DNA contains two nucleotide chains DNA contains two nucleotide chains wound together in a helical shape.wound together in a helical shape.
Each human chromosome is a single, longEach human chromosome is a single, longDNA molecule compacted by proteins.DNA molecule compacted by proteins.
A gene is a sequence of nucleotides that A gene is a sequence of nucleotides that provides instructions for producing a protein.provides instructions for producing a protein.
6
30,000
Characteristics of Humans As Living OrganismsCharacteristics of Humans As Living Organisms
Living things maintain homeostasis Living things maintain homeostasis = state of internal constancy= state of internal constancy
Characteristics of Humans Characteristics of Humans As Living OrganismsAs Living Organisms
• Human beings respond Human beings respond to stimuli from their to stimuli from their environmentenvironment
Characteristics of Humans as Characteristics of Humans as Living OrganismsLiving Organisms
• Human beings adapt and evolveHuman beings adapt and evolve
Evolution = change in characteristicsEvolution = change in characteristicsover timeover time
Adaptation = characteristic that Adaptation = characteristic that promotes promotes
survival and survival and reproduction reproduction
How Do We Categorize How Do We Categorize Living Things?Living Things?
• Three DomainsThree Domains– EukaryaEukarya– ArchaeaArchaea– BacteriaBacteria
Domain Eukarya
Domains Archaea and Bacteria
prokaryoticprokaryotic
eukaryoticeukaryotic
Eukaryotes have a membrane-bound
nucleus and extensive internal membranes
Prokaryotes have no membrane-bound nucleus and few
internal membranes
How Do We Categorize How Do We Categorize Living Things?Living Things?
• Eukarya has four kingdomsEukarya has four kingdoms– Protista: mostly single celledProtista: mostly single celled– Fungi: multicellular, digest Fungi: multicellular, digest
nutrients outside the bodynutrients outside the body– Plantae: multicellular, Plantae: multicellular,
photosyntheticphotosynthetic– Animalia: multicellular, Animalia: multicellular,
internal digestioninternal digestion
Domain Eukarya
Kingdom Animalia
Kingdom Plantae
Kingdom Fungi
Kingdom Protista
Increasing Levels of Organizational HierarchyIncreasing Levels of Organizational Hierarchy
organ system
organism
population Members of the same species in the same area
communityInteracting populations in the same area
ecosystemCommunity + Non-living factors
Biosphere
All ecosystems on earth: zones of air, land and water that support life
Characteristics of Humans As Living OrganismsCharacteristics of Humans As Living Organisms
• Human beings are members of the biosphere Human beings are members of the biosphere
Characteristics of Humans as Characteristics of Humans as Living OrganismsLiving Organisms
Human Beings Human Beings 1.1. are highly organized with levels from are highly organized with levels from
cellscellstissuestissuesorgansorgansorgan systems organ systems 2. acquire and use materials and energy.2. acquire and use materials and energy.3. maintain homeostasis.3. maintain homeostasis.4. respond to stimuli from their environment. 4. respond to stimuli from their environment. 5. reproduce, grow and develop. 5. reproduce, grow and develop. 6. adapt and evolve. 6. adapt and evolve. 7. are members of the biosphere. 7. are members of the biosphere.
Unique Characteristic of HumansUnique Characteristic of Humans
• Human beings have a cultural heritageHuman beings have a cultural heritage
How Do Biologists Study Living Things?How Do Biologists Study Living Things?
ObservationNew observations
are made, and previousdata are studied.
HypothesisInput from various sources
is used to formulate atestable statement.
ExperimentThe hypothesis is
tested by experimentor further observations.
ConclusionThe results are analyzed,
and the hypothesis issupported or rejected.
Scientific TheoryMany experiments andobservations support a
Theory.
PrincipleA theory supported by evidence over a long
period of time,
Scientific Scientific MethodMethod
How Do Biologists Study Living Things?How Do Biologists Study Living Things?
Scientific Method
Hypothesis
Conclusion
Observations
Experiment/Observations
Specific nutrients in almonds can Specific nutrients in almonds can reduce LDL cholesterol in people reduce LDL cholesterol in people with high blood lipid levels.with high blood lipid levels.
People who eat almonds as snacks People who eat almonds as snacks have improved blood lipid profiles. have improved blood lipid profiles.
How Do Biologists Study Living Things? How Do Biologists Study Living Things?
Experimental DesignExperimental Design•Subjects divided into Subjects divided into
– Experimental (Test) GroupExperimental (Test) Group– Control Group: treated like test group Control Group: treated like test group
except for a difference in one variable except for a difference in one variable being testedbeing tested
•Avoiding Bias in Human StudiesAvoiding Bias in Human Studies– Blind Study: subject does not know if they Blind Study: subject does not know if they
are assigned to test or control groupare assigned to test or control group– Double-blind Study: neither subject nor Double-blind Study: neither subject nor
investigator know who is assigned to test investigator know who is assigned to test and control groups and control groups
How Do Biologists Study Living Things?How Do Biologists Study Living Things?
Scientific Method
Hypothesis
Conclusion
Observations
Experiment/Observations
Specific nutrients in almonds can Specific nutrients in almonds can reduce LDL cholesterol in people reduce LDL cholesterol in people with high blood lipid levels.with high blood lipid levels.
People who eat almonds as snacks People who eat almonds as snacks have improved blood lipid profiles. have improved blood lipid profiles.
Subjects used three equal calorie Subjects used three equal calorie supplements in separate one month supplements in separate one month periods:periods:
Muffins (low saturated fat)Muffins (low saturated fat)Half Almonds + Half MuffinsHalf Almonds + Half Muffins
Almonds Almonds
Experimental ResultsExperimental Results
Do the results show that almonds change Do the results show that almonds change the LDL cholesterol levels in these subjects?the LDL cholesterol levels in these subjects?
What characteristics of almonds would accountWhat characteristics of almonds would accountfor the difference from the control supplement?for the difference from the control supplement?
How Do Biologists Study Living Things?How Do Biologists Study Living Things?
Scientific Method
Hypothesis
Conclusion
Observations
Experiment/Observations
Specific nutrients in almonds can Specific nutrients in almonds can reduce LDL cholesterol in people reduce LDL cholesterol in people with high blood lipid levels.with high blood lipid levels.
People who eat almonds as snacks People who eat almonds as snacks have improved blood lipid profiles. have improved blood lipid profiles.
Subjects used three equal calorie Subjects used three equal calorie supplements in separate one month supplements in separate one month periods:periods:
Muffins (low saturated fat)Muffins (low saturated fat)Half Almonds + Half MuffinsHalf Almonds + Half Muffins
Almonds Almonds
Monounsaturated fats (and possibly protein and fiber) Monounsaturated fats (and possibly protein and fiber) of almonds caused a decrease in LDL cholesterol.of almonds caused a decrease in LDL cholesterol.