Pictured below are Louis Pasteur’s original drawings of swan-necked flasks.

Describe how Pasteur’s experiments provided convincing evidence to falsify the concept of spontaneous generation.

State the function of life in Paramecium that is carried out by:

cilia.

State the function of life in Paramecium that is carried out by:

the contractile vacuole. 

Discuss the advantages and disadvantages of the use of adult stem cells.

Explain the role of decomposers in an ecosystem.

a. spontaneous generation is life appearing from nothing / from non-living / cells only come from pre-existing cells/life 

b. broth/culture medium (for bacteria) (used/placed) in flasks 

c. broth boiled/sterilized «in some flasks» to kill microbes 

d. no clouding/signs of bacterial growth/reproduction / microbes did not appear «in flasks of boiled broth» 

Allow bacteria or organisms instead of microbes.

e. after necks of flasks were snapped boiled broth became cloudy/growth of microbes 

f. because microbes from the air contaminated the «boiled» broth 

g. curved necks allowed indirect exposure to air but prevented entry of microbes

movement/locomotion
OR
feeding/nutrition

homeostasis
OR
maintain osmotic balance / expels «excess» water / maintains «cell» water content

Advantages:

a. «adult stem cells» can divide «endlessly» / can differentiate 

b. «adult stem cells» can be used to repair/regenerate «tissues» 

c. fewer ethical objections «than with embryonic stem cells» 

d. adults can give «informed» consent for use of their stem cells 

e. adult source is not killed / «source» would not have grown into new human / no death of embryos used to provide stem cells 

f. no rejection problems / patient’s own cells used 

g. less chance of cancer/«malignant» tumor development «than from embryonic stem cells» 

h. most tissues in adults contain some stem cells

Disadvantages:

i. difficult to obtain/collect/find in adult body/very few available 

j. some «adult» tissues contain few/no stem cells 

k. «adult stem cells» differentiate into fewer cell types «than embryonic cells» /OWTTE

a. saprotrophs/decomposers feed on/break down dead «organic» matter 

b. saprotrophs/decomposers release energy «heat» accelerating decomposition/warming soil 

c. saprotrophs/decomposers recycle nutrients / make nutrients available (to producers)
OR
improves soil fertility / returns nutrients (minerals/nitrates/phosphates/carbon)to soil/water/environment 

d. saprotrophs/decomposers detoxify waste