APT, Water and Inorganic Ions Flashcards
Cells constantly hydrolyse ATP to provide energy.
Describe how ATP is resynthesised in cells. (2)
- from ADP and Pi
- by ATP synthase
- during respiration
Give two ways in which hydrolysis of ATP is used in cells.
- to provide energy for other reactions
- to add phosphate to other substances and make them more reactive
The scientists concluded that an increase in phosphate in the embryo was linked to growth of the embryo.
Suggest two reasons why an increase in phosphate can be linked to growth of the embryo. (2)
- phosphate required to make DNA
- phosphate required to make ATP
The chilling requirement of seeds of certain plant species is considered to be an adaptation for survival in countries with seasonal changes in environmental conditions.
Suggest how this adaptation may enable these plant species to survive and respond to seasonal changes. (3)
- seeds remain dormant in winter so this is when growth occurs
- seeds/ plants develop in the summer
- plants photosynthesise in warmth
- produce more offspring in spring
Describe how an ATP molecule is formed from its component molecules.(4)
- 3 components: adenine, ribose/ pentose, 3phosphates
- condensation reaction
- ATP synthase
As shown in figure 1 ATP synthase has two functions.
-it catalyses the synthase of ATP
-it allows the movement of h+ ions
Suggest how the shape of ATP synthase allows it to have these two functions. Explain your answers. (4)
Catalyses synthase of ATP:
- active site complementary to ADP and Pi
- enzyme-substrate complex forms
Allows the movement of h+ ions:
- channel in membrane
- allows facilitates diffusion of H+ ions
Water and inorganic ions have important biological functions within cells.
Give two properties of water that are important in the cytoplasm of cells.
For each property of water, explain its importance in the cytoplasm. (4)
- Polar molecules
BIOLOGICAL IMPORTANCE: acts as a universal solvent - Reactive
BIOLOGICAL IMPORTANCE: takes place in hydrolysis
Water and inorganic ions have important biological functions within cells.
Other than sodium, name one inorganic ion and give one example of its biological importance in a cell. (2)
- hydrogen
- pH is calculated from conc of h+ ions, pH outside of normal range can denature proteins and slow enzyme-controlled reactions
Water and inorganic ions have important biological functions within cells.
Compare and contrast the processes by which water and inorganic ions enter cells. (3)
- both move down conc gradient
- both move through channel membrane
- ions can move against conc gradient by active transport
Cells constantly hydrolyse ATP to provide energy.
Describe ow ATP is re synthesised in cells. (2)
- ADP+ Pi = ATP
- by ATP synthase during respiration
Cells constantly hydrolyse ATP to provide energy.
Give two ways in which the hydrolysis of ATP is used in cells. (2)
- to provide energy for other reactions
- to add phosphate to other substances and make them more reactive
Name the type of reaction used to break down phospholipids to release phosphate. (1)
Hydrolysis
See Q3 in as booklet.
The scientist concluded that an increase in phosphate in the embryo was linked to the growth of the embryo.
Suggest two reasons why an increase in phosphate can be linked to growth of the embryo. (2)
- phosphate required to make RNA
- phosphate required to make DNA
- phosphate required to make ATP
See Q3 in as booklet.
The chilling requirement of seeds of certain plant species is considered to be an adaptation for survival in countries with seasonal changes in environmental conditions.
Suggest how this adaptation may enable these plant species to survive and respond to seasonal changes. (3)
- seeds/ embryos remain dormant in winter so this is when growth occurs
- seeds/ plants develop in summer
- plants photosynthesise in warmth
- produce more offspring in spring
Give three properties of water that are important in biology. (3)
- is a solvent
- high specific heat capacity
- has cohesion/ hydrogen bonds between molecules
the student produced the sucrose solutions with different concentrations from a concentrated sucrose solution.
Name the method she would have used to produce these sucrose solutions. (1)
Dilution series
State and explain the property of water that can help to buffer changes in temperature. (2)
- high specific heat capacity
- take a lot of heat to change temp
Water is used to hydrolyse ATP.
Name the two products of ATP hydrolysis. (1)
- ADP
- Pi
Describe the roles of iron ions, sodium ions, and phosphate ions in cells. (5)
IRON:
- haemoglobin binds to oxygen
- allows oxygen to be transported
SODIUM:
- co-transport of glucose and amino acids into cells
- sodium moved out by active transport
- create a sodium conc gradient
- effect osmosis/ water potential
PHOSPHATE:
- effects osmosis
- joins nucleotides
- used to produce ATP
- phosphorylates other compounds making them more reactive
- hyrdrophillic heads
Explain the arrangement of phospholipids in. Cell-surface membrane. (2)
- bilayer
- hydrophobic tails are repelled from water
- hydrophilic heads are attracted to water
Describe how an ester bond is formed in a phospholipid molecule. (2)
- condensation reaction
- between glycerol and fatty acid
State and explain the property of water that helps you to prevent temperature increase in a cell. (2)
- high specific heat capacity
- buffers against sudden temp changes
See Q8 in as booklet.
Using figure 8 and the info provided, what can you conclude about amino acid uptake by G cells and by H cells? (3)
- amino acid uptake by active transport
- cyanide reduces amino acid uptake
- ATP production stops on membrane
