module 4a life_science

Teaching Life Science

Most Important for Elementary Science

•  Keep excitement alive.

•  Encourage and empower curiosity.

•  Avoid misconcep@ons.

What to teach -‐-‐ Themes

•  Inquiry •  PaEerns •  Systems

•  Cycles (constancy and change) •  Structure and Func@on

What to teach – Skills

•  Inquiry –  observe, ask ques@ons –  classify –  use tools, choose tools – measure, with non standard and standard –  conduct experiments, design experiments

•  Models –  use – make –  evaluate and list limita@ons

What to teach -‐-‐ Content

– Living versus non-‐living – Living things as systems – Growth and change (life cycles) – Habitats – Adapta@ons –  Inheritance

PaEerns

•  Classifica@on – Ar@cula@ng the rules – Recognizing that humans, not nature, classify – Appreciate the usefulness

Cycles (Constancy and Change)

•  In our universe, change is the result of forces. •  In our universe, change is inevitable. •  Constancy is seen in –  the paEerns of change, –  the concepts underlying change, and –  laws of nature

Cycles (Constancy and Change)

Drawing from hEp://www.nature-‐giVs.com/frog-‐life-‐cycle-‐[email protected]

Systems

•  Student MUST have an opera@onal defini@on of systems. That means they should: –  Recognize something as a system –  Know that systems have parts, and that each part has a specific role in the system

–  That the parts affect each other (a change in one part will have effects on other parts of the system)

–  The system as a whole is more than just the sum of its parts

–  Systems need energy –  Systems break down

Systems

•  Body systems – plants and animals •  Food webs •  Ecosystems – habitats, biomes •  Hints for teaching –  Trace the energy –  Trace the maEer –  Specifically point out the rela@onships among the parts

–  Specifically remind the students that this is system; frequently ask them to iden@fy the characteris@cs of a system

Systems

•  Ask ques@ons like: – What is it about this … that makes it a system?

– What do we know about this because it is a system?

– What parts make up this system? – What part does this … play in the system? – What would happen to the system if this part were (removed; not working, etc.)?

Systems •  Some systems are physically linked, like the parts of a plant or animal.

•  Wrong: Have students memorize the parts of a plant and the func@on of each part.

•  Right: Write the needs of all living things on the board and give each group of students a full plant (best) or plant picture (ok). Have them look at the structures and try to deduce which need that structure would meet for the plant. Discuss it as a class to clarify any misconcep@ons. THEN have them draw, label, write func@ons, etc.

Systems

•  Some systems are linked through interdependence, rather than physical connec@on. Examples: food webs, habitats, biomes.

Just for Fun

1.  Why is this a system system?

2.  What do we know about this because it is a system?

3.  What parts make up this system? 4.  What part does this … play in the system? 5.  What would happen to the system if this part

were (removed; not working, etc.)

Just for Fun •  In groups of 3 or 4, select one of the following and discuss it, answering the following ques@ons:

Discuss this system.

Structure and Func@on

•  STRESS this constantly. •  Structure and func@on are forever-‐and-‐ever @ed together.

•  Which came first, the chicken or the egg? Doesn’t maEer. They are linked.

Structure and Func@on

Living and Non

•  List the characteris@cs of living things •  (Remember our “concept aEainment strategy”? *

•  What children think: •  hEp://ed-‐share.educ.msu.edu/PMsum02/almostsmart/AlmostSmart/Research/livmov.htm

•  Video: Living vs. Non-‐living •  hEp://ed-‐share.educ.msu.edu/PMsum02/almostsmart/AlmostSmart/Research/living.mov

Living vs. Non-‐living

•  Anything that is alive or has been alive has cells (or the remnant of cells).

Living vs. Non-‐living: Misconcep@ons to Avoid

•  All living things need oxygen. •  Living things move; non-‐living things do not.

•  Must have food.

•  Living things grow; non-‐living things do not. •  Living things can come from non-‐living things.

Ecosystems and Habitats Common Misconcep@ons

•  A species high on the food web is a predator to everything below it.

•  Energy accumulates in an ecosystem so that a top predator has all the energy from the organisms below it.

•  Carnivores can exist in a plant free world if their prey reproduce enough.

Where are the misconcep@ons?

True or False

•  Roots provide food for the plant. •  Plants make food for us to eat. •  Plants and animals both take in oxygen during respira@on.

•  Many plants and animals produce eggs during the process of reproduc@on.

•  A seed in a plant is like an egg in an animal. •  Plants do not have sexual reproduc@on. •  To sprout, seeds need water, oxygen, soil, and sunlight.

Plants – Common Misconcep@ons

•  Plants obtain their energy directly from the sun.

•  Plants have mul@ple sources of food (heterotrophic as well as autotrophic).

•  Carbon dioxide, water, and minerals are food. •  Plants feed by absorbing food through their roots.

•  Plants use heat from the sun as a source of energy for photosynthesis.

Berthelsen, B. (1999). Students Naïve Concep;ons in Life Science. MSTA Journal, 44(1) (Spring’99), pp. 13-‐19. h;p://www.msta-‐mich.org

Plants – Common Misconcep@ons

•  Sunlight is a food. •  Sunlight is composed of molecules

•  .Sunlight is “consumed” in photosynthesis.

•  Plants absorb water through their leaves •  Plants produce oxygen for our benefit.

Berthelsen, B. (1999). Students Naïve Concep;ons in Life Science. MSTA Journal, 44(1) (Spring’99), pp. 13-‐19. h;p://www.msta-‐mich.org

Plants – Science Teachers Need to Know About…

Photosynthesis •  Plants respire (take in oxygen and release carbon dioxide) as well as conduct photosynthesis.

•  Plants store the energy from sunlight as starch or sugar for their own use.


Seeds

•  Do not need sunlight to germinate.

•  Do not need “warmth.” •  The embryo can grow un@l it runs out of stored food.


Plant reproduc@on •  Plants have male and

female, eggs and sperms. •  Males may go “in search”

of females.

•  Volvox reproduc@on •  hEp://

www.youtube.com/watch?v=fqEHbJbuMYA&feature=related

Animals

•  Only large land mammals are animals. •  Penguins and turtles are amphibians because they are both in and out of water.

•  Whales, jellyfish, and starfish are all fish.

•  Respira@on is synonymous with breathing.

Animals

•  Key to teaching about animals is to help students understand scien@fic classifica@on…

This is a because

Animals

•  …and ADAPTATION.

Adapta@on

•  The most seriously misunderstood concept in elementary life science.

•  Adapta@on had nothing to do with the common meaning of “to adapt.”

•  Adapta@on is not: – an ability to adapt to one’s environment.

– a change an organism made it fit into its environment.

Adapta@on

•  Organisms do not acquire traits because the trait is needed for survival; they survive because they happen to have that trait.

Adapta@on

•  Behaviors may be acquired (you may teach your dog a trick), but…

•  Behavioral adapta3ons are ins@nc@ve, not learned (it is in the genes of the organism).

Adapta@on

•  Structural changes can occur as the result of the lifestyle of the organism (your dog may have a shiny coat because you brush it a lot) but these are not passed on to the offspring.

•  Structural adapta3ons may develop over the life of the organism, but they may not be acquired. They are in the genes and are passed on to the offspring

Adapta@ons

Answer these ques@ons. In answering them, state whether this is an adapta@on or not.

1.  Why do I have canine teeth (incisors)? 2.  Why does my cat like to play with wiggly

toys? 3.  Why do my children eat pie for dessert

frequently? 4.  Why can I speak English without an accent,

but speak French with an accent?

Adapta@on

Give explana@ons for the following: 1.  An oEer has a special niche in the pond

environment.

2.  Changing habitats (for example, due to human building and development) may lead to the disappearance of species.

3.  Disappearance of species and the appearance of new species is inevitable.

Remember!

•  Keep excitement alive. •  Encourage and empower curiosity.

•  Avoid misconcep@ons.

Image from hEp://www.gymboree-‐ph.com/images/science1.gif

module 4a life_science

Education