DO NOW (1) 1.Design an experiment that shows the movement of starch and iodine through a semipermeable membrane  How can we tell where starch is present? 2.Why does a potato lose weight when placed in a saltwater solution?

Photosynthesis

DO NOW (2) 1.Why does water move into cells when cells are placed in distilled water? 2.What is the difference between active transport and passive transport (diffusion)?

DO NOW (3) 1.Plant and animal cells are different. Which organelle belongs to a plant cell, animal cell or both (mitochondria, chloroplast, cell wall, cell membrane). 2.How do organisms obtain/get nutrition? Quiz Friday on Photosynthesis Test next Wednesday (photosynthesis & Respiration)

How do organisms obtain nutrition? There are 2 ways: 1.Heterotrophs Unable to synthesize own food. Ingests food (nutrients) produced by, or available in, other organisms. 2.Autotrophs Autotrophs make their own food. Also called producers Plants do not need to ingest food. Sugar (nutrients) synthesized during photosynthesis (some organisms)

Why do living things need nutrition? For energy! Energy is needed for: – Growth – Maintaining homeostasis All life Functions GRRRNETS – Reproduction Everything

What are some types of autotrophs? Mostly green plants and some single-celled organisms – Trees, grass, bushes, photosynthetic bacteria, algae

How do autotrophs make food? Photosynthesis Photo I Synthesis = Light I Creates Many autotrophs are plants. How are plants different from animals? (Think cellular)

Photosynthesis Equations Carbon dioxide + water + light glucose+ oxygen 6C H 2 O + Light C 6 H 12 O 6 + 6O 2 Inorganic molecules Organic molecule + O 2 Sun’s Energy Stored chemical energy (bonds)

Photosynthesis in a Story Photosynthesis takes place in the chloroplasts of green plants. Chloroplasts contain the pigment chlorophyll which traps radiant energy from the sun! The Sun’s energy splits water into Oxygen (waste product) and Hydrogen The hydrogen is then combined with Carbon Dioxide to create glucose Glucose stores the Sun’s energy and Oxygen is used by plants and animals to get the energy from glucose (respiration)

Hmmm… Is the Sun the Ultimate source of energy in most living organisms? If photosynthesis did not take place, would we have oxygen to breath?

DO NOW (4) 1.What is needed (reactants) for photosynthesis? 2.What are the products of photosynthesis? 3.Why does photosynthesis take place? Why is it important?

Photosynthesis Photosynthesis - Process where the Sun’s energy is used to synthesize organic compounds. Sun’s energy is converted into chemical energy stored in the bonds of glucose (organic compound produced). Is the Sun the Ultimate source of energy in most living organisms? If photosynthesis did not take place, would we have oxygen to breath? Would we have food to eat?

Where does photosynthesis take place? In chloroplasts found inside the mesophyll cells of leaves – Does photosynthesis take place in leaf stems or a tree trunk?

Why are chloroplasts important for photosynthesis? Chloroplasts contain chlorophyll – Chlorophyll – Why are plants green? – What colors are absorbed best?

Does the color of light affect photosynthesis? What is your conclusion (Why): FriSatSunMonTuesWedThurs Green0--4 mm9 mm17 mm20 mm Blue6 mm--43 mm50 mm67 mm67 mm** Red2 mm--59 mm64 mm84 mm87 mm Yellow Clear0--37 mm49 mm70 mm75 mm No light filter mm66 mm75 mm

There are two parts to photosynthesis How does photosynthesis make glucose?

Take place in chloroplasts In leaves Only occurs in Light Sun’s light energy captured by chlorophyll – Light energy is used to split H2O into H2 and O2 Oxygen is given off as a waste product 1 - Light-dependent reactions:

2 - Light-independent reactions: Takes place in chloroplast in leaves Can take place with or without light CO2 is combined with H2 to create GLUCOSE – Glucose = stores the energy of the Sun in bonds. This is chemical potential energy

Exit question: How is glucose synthesized?

Do Now Do Now (5) 1.Finish the formula: ______________ + ________ + light __________+ __________ 2.Questions: – # 2, 6, 24 in packet

What is going on here? The “thing” in the beaker is a green elodea plant. What are those little bubbles in the test tube?

How can we measure the rate of photosynthesis? Measure the amount of product produced! – How?

What could speed-up or slow-down the rate of photosynthesis? 6C H 2 O + Light C 6 H 12 O 6 + 6O 2

Conclusions: Light intensity: Amount of CO 2 : Color of light :

How do plants get materials needed for photosynthesis? Roots Stems Leaves

Roots Many active transport proteins – Mineral ions and nutrients are actively transported into the roots This creates low water concentration in the roots… So, how does water get into the roots?

Roots Water diffuses (osmosis) into the roots and is trapped by a special membrane surrounding the roots. This creates pressure and the only place to go is up! Why does the water have to go up to the leaves?

Test yourself… Write 2 of the 4 equations of photosynthesis without looking. Show reactants and products.