May 2021 SL Flashcards
In mammals, mature red blood cells are specialized in that they lack nuclei, mitochondria or
ribosomes. Which statement applies to red blood cells?
They cannot produce new enzymes.
What do chloroplasts and mitochondria have in common?
Both are found in the cells of Filicinophyta.
The Davson–Danielli model of membrane structure proposed that membranes were composed of a
phospholipid bilayer that lies between two layers of globular proteins. What evidence supported this model?
An electron micrograph that showed two dark lines with a lighter band in between
A human organ is being prepared for transplant. In what type of solution must it be bathed?
A solution with the same osmolarity as the organ tissue
Which living structure is an exception to the cell theory?
Striated muscle fibres
Which statement applies to cholesterol?
It impacts membrane fluidity.
What is the mitotic index?
0.25
What distinguishes cellulose from glycogen and starch?
Cellulose has a structural role whereas starch and glycogen function in energy storage.
The hydrolysis of a pure sample of an organic molecule produces a pentose sugar, thymine,
guanine and cytosine. What other substances could be expected to be present in the
hydrolysed sample?
Phosphate
Which molecule is depicted in the diagram?
A saturated fatty acid
What is a difference between aerobic respiration and anaerobic respiration in yeast?
Anaerobic respiration produces ethanol, aerobic respiration does not.
What is the term for the attraction of water molecules to other water molecules?
Cohesion
What is the approximate reduction in body mass that a person of height 155cm and mass 95kg
would have to lose to reach normal body mass?
36kg
Which statement applies to enzymes?
Enzyme function depends on collisions between substrate and active sites.
Which enzyme is matched to its function?
DNA polymerase forms a covalent bond between DNA nucleotides
If a plant is exposed to light, which colour of light would lead to the lowest rate of oxygen release
by a green plant?
Green
What is the relationship between the two adult sea urchins?
They are clones.
Which statement applies to meiosis and mitosis?
Separation of chromatids occurs in both meiosis and mitosis.
Which genotype would be normally found in a gamete?
RS
Over time, the hull of a sunken ship may become colonized by a wide range of marine organisms.
What term is used to describe all of the organisms living in and on a sunken ship?
A community
In a typical terrestrial ecosystem, which trophic level would have the highest biomass?
Autotrophs
Which process results in decreased variation?
Natural selection
A locust is an arthropod. For invertebrate groups, which recognition feature is found only in arthropods?
Jointed appendages
A dichotomous key can be used to distinguish four types of plant. Which of the plants could be
a bryophyte?
Vascular tissue present . . . . . . . . . . . . . . . . . . . . . . . . . . go to 2
Vascular tissue not present . . . . . . . . . . . . . . . . . . . . . . . Plant A.
