The study of interactions between living things and their environment.
The conversion of light energy to chemical energy which produces a carbohydrate and oygen.
Where does photosynthesis occur?
In plants and some bacteria, but not animals or fungi.
What are the rectactants of photosynthesis?
6CO2 + 12H2O
What are the products of photosynthesis?
C6H12O6 + 6O2 +6H2O
Photosynthesis occurs in what percent of land plants and water plants?
- 40% land plants
- 60% water plants
Where does Carbon Dioxide enter plants?
Enter through openings called stomata.
What regulates stomata cell openings?
Less than 1% of this is in the air.
What enters through the stomata and exits the stomata?
Carbon dioxide enters the stomata and water exists the stomata.
Where does photosynthesis occur on a plant?
Disk -like membrane structures covered with chlorophyll pigment.
Thick fluid inside chloroplasts.
Part of Photosynthesis takes place in the What?
Thylakoids and stroma.
True or False. Light and Dark reaction happens with Photosynthesis.
How does light energy occurs?
Light energy occurs in wavelengths.
What wavelengths visible light does photosynthesis occur?
Blue and red wavelengths.
How are wavelenghts lights determined?
Frequency of waves determines light color.
Where does light reaction occur?
It occurs in thylakoids.
In the light reaction what transport electrons, creates oxygen?
Where does the dark reaction occur?
In the stroma.
In the Dark Reaction, if CO2 is limited occurs in the stroma.
- Closed stomata to conserve water when hot
- Can cause photorespiration to occur.
- Example: Corn
- Avoid respiration
- Contain enzyme PEP
- can make sugar when stomata are almost closed
- Example: Cacti and orchids
- Open stomata only at night
- Carbon stored as acid
- Day acid converts to CO2 for photosynthesis
- Needs air
- C6H12O6 +6O2 --- CO2 + H2O + ATP
- 1 Glucose -- 36 ATP
- Without air no oxygen
- ex: happens in your muscles
What does fossil fuel and deforestation do to the atmosphere?
- Adds more carbon dioxide
- Increases temperature
True or False. CO2 has increased in the past 50 years.
Photosynthesis converts CO2 to what product?
What is the byproduct of respiration?
What are the effects of global warming?
- Rise in sea levels
- Global melting of glaciers
- Loss of habitat for temperature sensitive species
- More severe storms
The effects of global warming on C3 plants.
Increased growth with increased CO2 levels. Gives C3 plants an advantage over C4 plants.
What are factors that can have an effect on plants?
- Moisture availability
- Climatic extremes( Flood/Drought)
- Soil nutrient availability
- pests and diseases
True or False. Some plants may develop more stomata in response to elevated CO2.
False. Less stomata in response to elevated CO2. Increases temperature.
What are some methods of reducing CO2 in the atmosphere?
- Plant forests
- Reduce plowing of agriculture fields
- Genetic engineering
- Store in geologic features
- Inject into oceans
All the individuals of a species in a given area.
What are ways to measure the size of a population?
- Basic census
- Mark recapture
All individuals counted
Some individuals trapped, marked, released, note number of marked individuals in later captures.
What determines population size?
What is a clumped population?
High densities in resource-rich areas, low densities elsewhere.
What is a uniformed population?
Spacing between individuals tend to be equal.
What is a random population?
No compelling features pushing individuals together or apart.
Example of exponential growth.
Human population. J-shaped.
What was the growth rate of human population 2000 years ago?
0.1% per year.
What was the human population growth rate by 1750?
2% per year.
What is the current population growth rate now?
1.2% per year. 77 million people per year.
What are populations limited by?
Environmental resources: food, water, shelter, and space.
Max number of individuals that can be supported indifinitely in a given environment.
- Factors that increase with population size.
- Limited food supply, increased risk of disease, increase in waste levels.
- Can cause decrease in birth rates, increase in death rates, or both.
- not influenced by population numbers.
- Droughts, temperature extremes, natural disasters.
- Time lag between when humans reduce birth rates and when population growth begins to slow.
- example: childrens grow and have children.