Topic C: Interaction and interdependance

How many phosphate groups does ATP have?

three

What is the basic diagram/structure of ATP?

1x Adenine Base, 1x Sugar, 3x Phosphate group

Define ATP

The energy currency of a cell. It provides the temporary storage of energy and the temporary transport of energy.

What are the properties of ATP that makes it a suitable energy source within cells?

1. Stable and neutral pH

2. Soluble in water

3. Cannot pass freely through the cell membrane

4. Third phosphate group can be easily removed to release energy (hydrolysis)

5. Process can be reversed (reaction is cyclic)

Why can ATP NOT pass freely through the cell membrane?

Because ATP is polar (hydroPHILIC), therefore cannot go through the hydrophobic phospholipid bilayer of the membrane.

What is the importance of Atp not being able to pass freely through the cell membrane?

So no energy escapes the cell

How can atp be transported within a cell?

through transport organelles like vacuoles or vesicles

What are the three types of life processes that require energy from ATP?

• Synthesising macromolecules

• Active transport

• Movement

Why is atp important in synthesising macromolecules?

It provides energy necessary to fuel chemically unfavourable anabolic (endothermic) reactions.

What is Atp’s role in active transport

Pumping of ions or other particles across a membrane against the concentration gradient requires energy from ATP

• atp is used to cause chage from the more stable to the less stable conformation

Why is ATP required for movement within the cell (with examples)

Within the cells:

• e.g. chromosomes are moved to the poles during mitosis and vesicles move to transport materials within cells

• larger amounts of energy is needed to change shape of a cell → e.g. diving cell pinches apart during cytokinesis

Why is atp requried for movement outside the cell (locomotion + give examples)

e.g. muscle cells when contracting, phagocytes in the human blood system when moving to sites of infection

Define respiration

The chemical process of breaking down carbon containing compounds (macromolecules) to release the energy that is stored within that is later used to produce ATP (e.g. carbs + lipids)

Define ventilation

The physical process of moving air into and out of the lungs through inhalation and exhalation - driven by the contraction and relaxation of multiple muscles

define gas exchange

Movement of main gases (Co2 and O2) between the blood streams and the alveoli of lungs via simple diffusion

Word equation for aerobic respiration

Glucose + Oxygen → water + carbon dioxide + (30+) ATP

How is energy released in chemosynthesis

by oxidising inorganic substances like sulfides

Anaerobic respiration word equation in humans

Glucose → lactate acid (lactate)

Anaerobic respiration word equation in yeast/fermentation

Glucose → ethanol + carbon dioxide

In a human cell, which respiration occurs in the cytoplasm AND mitochondria?

Aerobic

which respiration occurs in the cytoplasm ONLY

Anaerobic

Pros of aerobic respiration

• Efficient

• Higher energy yield

• Lack of lactic acid

Pros of anaerobic respiration

• Efficient temporary substitute during high endurance sports

Why can lactic acid be toxic (during overaccumulation e.g.)

• Causes pH in cells to decrease

• Enzymes denatures → loses function

How is lactic acid typically ‘disposed’ of in the body?

• Tends to be released in blood stream

• Sent to detoxification organ of the body (liver)

How much ATP does aerobic respiration create?

+30 (~37) ATP

How much ATP is produced in anaerobic respiration?

2 ATP

Define autotrophs

Living things that make food to feed themselves (grass e.g.) using light to convert to energy

Define heterotrophs

Consume other living things for energy

Examples of autotrophs

Green plants, algae + cyanobacteria

Unique characteristic of how prokaryotes store chlorophyll

Store it in stacks and found near edge of cell membrane (do not have membrane bound chloroplasts)

Equation for photosythensis

6H20+6CO2 → C6H12O6 + 6O2

what is the by product in photosynthesis

Oxygen and glucose

State five uses of glucose produced during photosynthesis

1. cellular respiration

2. cellulose

3. starch

4. amino acids

5. oils and fats

Role of photosynthesis in plants

• cellular respiration

• allows production of carbon compounds (glucose)

• transformation/conversion of light energy into chemical energy

• Carbon based macromolecules like proteins and lipids

  • cellulose

  • starch

Why do most plants appear green (referring to wavelengths)?

Because it absorbs all other colours on the spectrum/wavelength BUT green

What is the purpose of chromatography?

to separate individual components within a complex mixture

What are some factors that influence the speed in which pigments go up during chromatography?

Size, polarity, or solubility in solvent → travel diff due to varying chemical features

What is the Rf value?

retention factor; distance moved by pigment/moved by solvent front

What are the purpose of current Co2 enrichment experiments?

• predict future rates of photosynthesis

• stimulate future atmospheric CO2 level