Biology module 5 Apologia

Phosphorylation

the transfer of energy when a phosphate group is moved between molecules

Pigment

an organic compound that reflects specific light wavelengths producing color

chlorophyll

a group of pigments found in green plants, algae and cyanobacteria that is necessary for photosynthesis

stroma

gel-like fluid found inside the inner membrane of chloroplasts

thylakoid

disk-shaped sac suspended in the stroma of chloroplasts. It is the site of the light reactions of photosynthesis

Grana

stacks of thylakoids

photosystem

a cluster of chlorophyll and other molecules, in the thylakoid membrane, that absorb light energy

Electron transport chain

a series of electron carrying molecules within a membrane that transfer electrons and release energy at each transfer

aerobic

requiring oxygen

anaerobic

without oxygen

glycolysis

the first stage of cellular respiration where glucose is split in half

kreb’s cycle

the second stage of cellular respiration where CO2 is used to complete the breakdown of pyruvic acid molecules, releasing energy

fermentation

a cellular process producing ATP without oxygen

Where is energy stored in ATP?

energy is stored in the bonds between the phosphate groups

Why is ATP better suited to provide the energy for cellular activities than glucose?

ATP stores just the right ammount of energy to power cellular actvites.

What is the benefit of the pigments in photosynthesis?

Pigments absorb the light energy needed to start photosynthesis

Would you expect a plant to grow well in only green light? Explain.

No, plants contain chlorophyll which does not absorb green light.

If you wanted to grow plants in a room with no windows, what colors of light would you choose to shine on the plants to maximize their photosynthetic potential? Why?

Using blue and red lights would give the best photosynthetic results for plants grown inside with no windows. This is because chlorohyll absorbs blue and red light wavelengths and reflects green light wavelengths.

What are the products of the light reactions? What is considered waste and what moves on to the Calvin cycle?

Oxygen, NADPH, and ATP are produced in the light reactions. Oxygen is considered a waste product and NADPH and ATP are used in the Krebs Cycle.

Explain how the structure of a leaf is designed perfectly for photosynthesis.

A leaf has mesophyll cells positioned so that the top cells have the most chlorophyll. This enables more direct sunlight to be used for photosynthesis. Stomata, pores in the leaf, allow for gas exchange. The water required for photosynthesis is carried from the roots of the plant to the leaves (where photosynthesis takes place) in veins/

Describe how ATP is generated in the light reactions.

Energy released (as elecrons are carried from photosystem to photosystem) in the electron transport chain is used to pump H+ ions back out of the thylakoid space powers ATP synthase to rotate. The rotation causes ADP and P close enough together to form ATP.

What is the function of NADPH?

NADPH carries energy-rich electrons to the Calvin Cycle, where it drops off the electrons to be used in making glucose.

How is the design of the chloroplast suited to its function?

The stacks (grana) of membrane bound thylakoids increases the membrane surface area for the light reactions (electron transport chain) to take place.

How is the design of the mitochondrion suited to its function?

The folded inner membrane increases the amount of membrane surface available for the electron transport chain.

What is the net gain of ATP in each stage of cellular respiration?

There is a net gain of 2 ATP in glycolysis, 2 ATP in the Krebs cycle, and 34 ATP in the electron transport chain.

Why can we say that most life on Earth is powered by the sun?

Autotrophs depend on the sun’s energy to power photosynthesis. Autotrophs and heterotrophs depend on the products of photosynthesis to convert the energy needed for life functions.

Compare photosynthesis and cellular respiration by its function, type of cell, location, reactants, products, electron carrier molecules, final electron acceptor of ETC, is ATP synthase used to produced ATP? If so where?, and equation

See table

If a plant cell needs energy for endocytosis, what does it use and where does the energy come from?

ATP supplies the energy a plant cell needs for endocytosis. The ATP comes from cellular respiration.

Compare the two types of fermentation

Both lactic acid fermentation and alcoholic fermentation break down glucose without oxygen. Lactic acid fermentation is performed in microorganisms and some animal cells while alcholoic fermentation fermentation is performed in mostly yeast cells. The wast product of lactic acid fermentation is lactic acid and the waste products of alcoholic fermentation are ethyl alcohol and carbon dioxide.

How is ATP made during fermentation?

ATP is made from glycolysis without oxygen

Red blood cells do not contain mitochondria. With your current knowledge of cellular respiration, can red blood cells break down glucose? Explain.

Yes, red blood cells can carry out glycolysis which occurs in the cytoplasm, not the mitochondria.

List four foods made by fermentation

bread, sauerkraut, cheese, yogurt (other options: pickles and soy sauce)