Unit 1: the Science of Life

Ch. 2: Features of Life & the Cell

Ch. 30 Populations & Communities

(selected sections)

WHAT IS BIOLOGY???

What do biologists study???• Do they all study the same thing?

http://www.keweenawnow.com/news/audubon_03_02/images/janet_audubon1.jpg

http://www.google.com/imgres?imgurl=http://armandfrasco.typepad.com/photos/uncategorized/arp2c.jpg&imgrefurl=http://www.moleskinerie.com/2006/06/tom_fricke_anth.html&usg=__y3iVJbR3BR8N5yP8icmuDdS5o-Y=&h=244&w=350&sz=55&hl=en&start=2&zoom=1&um=1&itbs=1&tbnid=Be4yQaEwUETH2M:&tbnh=84&tbnw=120&prev=/images%3Fq%3Danthropologist%26um%3D1%26hl%3Den%26tbs%3Disch:1

http://www.google.com/imgres?imgurl=http://blogs.panda.org/coral_triangle/files/2009/07/_dsc5137.jpg&imgrefurl=http://blogs.panda.org/coral_triangle/2009/07/15/wwf-malaysia-in-kudat-banggi-priority-conservation-area/&usg=__OfUaJjyofRtWfvYf93uULaOQaBE=&h=300&w=450&sz=55&hl=en&start=71&zoom=1&tbnid=YaZI-rTFBfWZbM:&tbnh=162&tbnw=206&prev=/images%3Fq%3Dmarine%2Bbiologist%26um%3D1%26hl%3Den%26sa%3DN%26biw%3D1259%26bih%3D815%26tbs%3Disch:10%2C1834&um=1&itbs=1&iact=hc&vpx=114&vpy=393&dur=1311&hovh=183&hovw=275&tx=150&ty=138&ei=IvB-TIaRJ4KClAel6KjtAw&oei=2e9-TMOBCsH98AaEkO3SAw&esq=6&page=4&ndsp=22&ved=1t:429,r:0,s:71&biw=1259&bih=815

What is an organism?

http://www.bigelow.org/bacteria/kingdom_2.jpg

Living vs. Non-living•How do we know?

http://www.animationlibrary.com/animation/25626/Fire_burns/http://www.animationlibrary.com/animation/18709/Dolphin_in_frame/

1. Living things are organized

• What is the smallest (basic) unit of life?

• What is the largest unit of organization?

2. Living things respond to stimuli

• What is a stimulus?

• Why is responding to stimuli so important?

Plants Responding to Light

3. Living things maintain homeostasis• What is homeostasis?

– Examples• body temperature

• CO2 level in blood

4. Living things grow• Both living & non-living things can grow….

–How is it different?

• What is the difference between growth & development?

& develop

5. Living things reproduce• What is the “goal” of reproduction?

• Biogenesis theory– “Like produces like…”

• What does this mean?

• Asexual vs. sexual reproduction

• Does every member of a species need to reproduce? Why or why not?

6. Living things have adaptations & evolve• What is an adaptation?

• Over time, beneficial adaptations are “selected for” & the population or species __evolve____________…

• Individual organisms do not evolve!!!

• Evolution explains the diversity of life.

• Pepper Moth “Game” http://www.techapps.net/interactives/pepperMoths.swf

• Principles of Natural Selection "Interactive"

• What is energy?

• Why is (chemical) energy needed?

7. Living things need energy

http://psych.fullerton.edu/mbirnbaum/psych466/CSW/growth-chart.jpghttp://www.irishcatholicdoctors.com/documents/images/CouplewithbabyWORD.jpg

http://www.sciencenewsforkids.org/articles/20031112/a228_2194.running.jpg

Where do organisms get energy?• Almost all the energy

organisms use comes from the sun!!!– What type of organisms

make their own food using the sun?

• examples

– What process do they use to make food (sugars)?

• What is the equation for photosynthesis?

• Where is the energy is stored?

Where do organisms get energy?

• Some organisms can make their own food without sunlight– chemosynthesis

• examples

Where do organisms get energy?

• What if an organism can’t make it’s own food? How would it get energy?

• What do we call organisms that have to eat to get energy?– What do we call consumers that eat:

• Plants?• Other animals?• Both plants & animals?

Where do organisms get energy?

• In most organisms, what process releases the energy stored in the bonds of food (glucose)?– What materials are needed?– What materials are made?

Where do organisms get energy?

• Cellular (aerobic) respiration…– What is the equation?– What other equation does it look like?

• What do organisms use the energy for?

Where do organisms get energy?

ATP

Where do organisms get energy?

• Can energy be recycled?– NO!!!! Just transferred & transformed…

• Usually released as heat

Energy & Nutrients

• Can nutrients be recycled?• Why must nutrients be recycled?

Energy & Nutrients

• What type of organisms recycle nutrients?– Detritivores

• Eat dead organisms• Ex. crabs, worms, snails

– Decomposers• Break down organic waste (poop)• Ex. fungi & bacteria

Where do organisms get energy?

Energy Flow: Food Chains

• Does energy only flow through individual organisms?– Community

• Food chains

***Arrow always points toward organism taking in the energy & away from the organism “giving up” the energy.***

Where do almost all communities

get their energy?

http://www.cnr.vt.edu/forsite/owlpellet/josh/PICTS/foodchain.jpg

1st trophic level

2nd trophic level

4th trophic level

3d trophic level

5th trophic level

Energy Flow: Food Chains

Energy Flow: Food Webs

http://usr-lazio.artov.rm.cnr.it/darwin2007/presentazioni/Modulo14_file/slide0242_image272.jpg

A Connecticut Food Web

What occurs as energy is passed to each trophic level?

Amount of energy passed on to the next

level.

Lost Energy

Lost Energy

• 10% Rule of Ecological Efficiency– ~10% energy is

passed to next level• ~90% lost

– Mostly as heat» Energy is NOT recycled.

Energy Flow: Energy Pyramids