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.