CELS M1 Questions
Hydrophobic molecules normally move across cell membranes by
) Simple diffusion
The movement of a molecule across the plasma membrane by facilitated diffusion requires which of the following
A concentration gradient for that molecule across the membrane
Which of the following statements BEST describes ATP
A versatile energy transfer molecule within the cell
How can ATP be produced?
ATP can be produced when hydrogen ions move down their gradient through ATP synthase
The diversity of life is classified into which of the following three domains
Bacteria, Archaea and Eukarya
Cellulose
Cellulose microfibrils give the wall strength and flexibility
The difference between euchromatin and heterochromatin is BEST described by
Euchromatin is normally transcriptionally active whereas heterochromatin is not
If all the polysaccharides of the primary plant cell wall are digested away, the remaining component(s) of the primary cell wall would be
Extensin and other proteins
What are integrins
Integrins are proteins that span the plasma membrane and connect the cytoskeleton to the ECM.
Reasons why a cell requires energy
Mechanical work Making new materials Transport Maintaining order
cytoskeleton
Microtubules are important for the correct functioning of cilia
Both animal and plant cells typically contain
Plasma membrane, Golgi apparatus, cytosol, ribosomes
Define the term plasmodesmata
Plasmodesmata are cytoplasmic channels in plant cell walls that allow continuity of the plasma membranes from two adjacent cells and cytoplasmic exchange between the cells
Dark reactions of photosynthesis occur in the _______ of the chloroplast
Stroma
Cellular respiration can BEST be described as
Taking electrons from food and giving them to oxygen to make water, and using the energy released to make ATP
The BEST description of natural selection is
The enhanced reproductive success of the members of a population best adapted to the environment
Which one of the following statements BEST describes the extracellular matrix
The mix of glycoproteins and proteoglycans that surrounds many cells
Which of the following statements about natural selection as a mechanism for evolution is TRUE
There must be variation within a population for natural selection to act on
Light reactions of photosynthesis occur in the _____ of the chloroplast
Thylakoid membrane
Pectin
acts as a glue (binds water to have gel-like properties).
Hemicellulose
acts to bind cellulose microfibrils
The cellulose microfibrils in the plantʹs primary cell wall are produced
by an enzyme complex spanning the cell membrane
DNA contains which of the following
deoxyribose sugar, phosphate group, thymine, adenine, guanine, cytosine
Extensin
enables wall flexibility (acts like a shock absorber)
Which of the following is found ONLY in secondary plant cell walls
lignin
function of organelles
provide separate compartments with discrete functions
The endosymbiont theory is BEST summarised as
the process by which prokaryotic cells became engulfed by early eukaryotes to establish a symbiotic relationship
Oxygen is produced in photosynthesis by the splitting of
water molecules in photosystem II.