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

• 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

• Hydrophilic

• Water hating

• Water loving (soluble)

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.

4 types of organic molecules make up the human body

2 or more atoms together make a molecule

You are what you eat

Estrogen (Estradiol)

Glucosewater

Carbohydrates: quick energy

• Monomers are sugar (glucose)– saccaride = sugar

• Oligosaccaride- sucrose or dextrins made of a few monomers

• Polysaccharides- starch, fiber

• CH2O

Lipids

• Oils, fats, waxes, sterols

• Energy storage, insulation, water proofing

• Hormones

• Hardening of membranes

• CHO

Amino Acids, Proteins

• 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

• DNA: Information storage, double stranded.

• RNA: Information transfer.

• ATP: Energy intermediates.

• Enzyme cofactors (NADH2).

• NOCH

SummaryYou 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

OsmosisMovement 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

• 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:– 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– Make reactions happen faster– Are reused– Are reversible– Are specific– Use cofactors (in order to function)

Enzymes are proteins so are susceptible to

• 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.