Human Biology
Bio 130
Nickolas V. Kapp Ph.D.
We have organized life and
assume some relationships.
A look at Human Biology
• Human Beings are related structurally and
physically to animals.
• In order to understand ourselves better we
study every living thing from viruses,
bacteria to mice and monkeys
• Science gives a best guess as to what is
going on in our bodies
Life Is able to…7 things.
• Be organized from
simple parts by basic
rules.
• Obtain energy and
matter from the
environment
• Sense and respond
• Reproduce, grow,
develop
• Have inheritance
• Evolve
• Maintain Homeostasis
• Our Culture separates
us from other living
things
How do we know these things?
The Scientific method
Hypothetico-deductive approach
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Making Observations
Asking questions
Forming hypothesis
Making Predictions
Testing by conducting
experiments
• Draw a conclusion
based on your results
• Things required
– The question must
have an answer
– You can only test a
single variable
– You need to use a
control.
– Perform double blind
tests.
• If the data from observation and
experimentation support the hypothesis
• We test it again.
• Hypotheses that are not supported are
abandoned.
• A THEORY is supported by an
overwhelming number of lines of evidence.
Critical Thinking Helps Us
Make Informed Decisions
What is not science?
• It happened to one person it can happen to
me.
• That’s the way its always been done so it
should work.
• ???
We are living organisms. The
Human Body is designed to
• Maintain internal operating conditions within
a set limits.
• Locate,acquire nutrients, process and dispose
of waste.
• Protect from injury, attack and wear and tear.
• Reproduce successfully.
• Laugh at bad jokes.
Homeostasis
• The adjustments that
every living organism
must do to preserve
their internal
environment
Modes of homeostatic control
• Negative feedback
– Thermoregulation
– At a setpoint the
effector is turned off
• A signal causes an
effect that reduces the
signal.
• Positive feedback
– Birth
– Only removal of the
stimulus reduces the
signal
• A signal causes an
effect that increases
the signal.
11 organ systems that help
maintain homeostatic control
• Integumentary
system
• Skeletal system
• Muscular system
• Nervous system
• Endocrine system
• Cardiovascular
system
• Lymphatic system
• Respiratory system
• Digestive system
• Urinary system
• Reproductive
system
Discussion
What does science and
Technology mean to you?
Topic 2 The Chemistry of Life
It’s the small things that make life
good. Nick Kapp 2000
The Natural World Consists of
Matter and Energy
• Matter: anything that has mass and
occupies space.
• Energy: the capacity to do work
• Which of these can be recycled?
The 4 most abundant elements of
life
• Elements, are the fundamental (smallest)
particles of matter.
– Nitrogen
– Oxygen
– Carbon
– Hydrogen
Some basic chemistry
• Isotopes: all have
same number of
protons but different
number of neutrons
• use?
– Radiodating
– Radiation therapy
– X-ray emission
• Important chemical
bonds
– Ionic: opposites attract
– Covalent: atoms share
electrons
– The polar covalent
bonds of water
• Why is water so
important to life?
The human body is 2/3 water
• Hydrophobic
• Water hating
• Water loving (soluble)
• Hydrophilic
Hydrogen ions play an important
role in life
• Molecules that donate a hydrogen ion (H+)
are called acids.
• Molecules that accept hydrogen ions are
called bases.
• The hydrogen ion concentration of a
solution is called the pH.
• Buffers minimize changes in ph.
The molecules of life:
organic molecules
• Monomer: one of something.
• Dimer: two of something.
• Polymer: many of something.
Estrogen
(Estradiol)
4 types of organic molecules
make up the human body
2 or more atoms together make a
molecule
You are what you eat
Glucose
water
Carbohydrates: quick energy
• Monomers are sugar (glucose)
– saccaride = sugar
• Oligosaccaride- sucrose or dextrins made of
a few monomers
• Polysaccharides- starch, fiber
• CH2O
Lipids
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Oils, fats, waxes, sterols
Energy storage, insulation, water proofing
Hormones
Hardening of membranes
• CHO
Amino Acids, Proteins
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AA is the monomer, Polymer is protein
Enzymes- catalysts that speed up reactions
Are sensitive to temperature, pressure, pH
Structural unit of hair, nails, cells, bone, cartilage
and skin
• Protease (All@ the detergent with protein)
• NOCH (some S)
Proteins are enzymes
• And how do enzymes work?
Nucleic acids
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DNA: Information storage, double stranded.
RNA: Information transfer.
ATP: Energy intermediates.
Enzyme cofactors (NADH2).
• NOCH
Summary
You are what you eat. Your body
requires that you consume all of its
subunits in your diet, or you use some
of your energy to make those
subunits.
Bad bricks make a bad house
Topic 3: The Cell
The smallest unit of life it the cell.
Can you think of anything smaller?
What is alive?
The cell theory of life
• All organisms are composed of 1 or more
cells.
• The cell is the smallest functional unit of
life.
• Cells only come from other cells.
• Cells maintain homeostasis.
– Cytology is the study of the structure and
function of a cell.
Two types of cells
• Eukaryotic
– Have internal
membrane bound
organelles
– Usually larger
– Usually individuals are
much more complex
– Most things you can
see
• Prokaryotic
– No internal membrane
bound organelles
– Individuals are simple
– Bacteria, most are too
small to see, most do
not cause disease
Physical properties that we will
use all semester long.
Diffusion
• Movement of molecules down a
concentration gradient
Osmosis
Movement of water across a semi
permeable membrane
Tonicity
Transport Mechanisms
• Passive transport: works by diffusion.
• Active transport: energy required to move
molecules across the membrane.
• Endocytosis: membrane wrap around
materials that go into cells.
• Exocytosis: membrane wrap around
materials that go out the cells.
Fig 2.8
Parts of the cell that you need to
know
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Cell membrane
Cytosol
Cytoskeleton
Microvilli
Cilia
Centrioles
Ribosomes
Endoplasmic reticulum
• Lysosome
• Mitochondria
• Nucleus
• page 42
• link
Pick your organelles
• Take 5 minutes in groups and research an
organelle
• Draw a picture and write it out on a card.
• Hand it in to Nick.
• Discuss
The cell membrane
• Function: gateway to life, the portals of the
cell, sticking together of tissue
• Structure:
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Phospholipids
Hydrophobic
Bilayer
Gateway proteins are embedded like a mosaic
Fig 3.3
Fluid Mosaic Model
Why are cells small?
Know the
arrangement of
Organells and
what they do
Metabolism
• The controlled capacity to acquire energy, break
apart and eliminate substances.
– Biosynthetic pathway: anabolism making molecules
– Degradative pathways: catabolism, breaking molecules
apart and harvesting the energy
• The sum of the chemical events that occur in the
body
– Substrate and Product
Substrates are
products to the
next enzyme
Enzymes
• Serve as catalysts, and speed up reactions.
• A series of enzymes together perform the
metabolic processes
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Make reactions happen faster
Are reused
Are reversible
Are specific
Use cofactors (in order to function)
Enzymes are proteins so are
susceptible to
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Heat
Cold
pH
Presence of cofactors
Summary of energy harvests
• Aerobic reactions.
– Glucose and Oxygen are combined to make
Carbon Dioxide and energy is transferred to
ATP (roughly 34) In mitochondria
• Anaerobic reactions
– Without Oxygen Glucose is converted to
Lactose and energy is transferred to ATP
(only2)
Alternative energy sources
• While the body is set up to harvest energy
from glucose, it can also use other
molecules.