Q&A MASTER SOLUTION PACK
◉ DNA (structure & function).
Answer: Structure:
Composed of phosphate, deoxyribose, A/T/C/G bases, the bases
bind to form a double stranded helix (twisted ladder).
A-->T or C-->G
Alternating phosphates and sugars form "uprights" while bases form
"rungs".
Functions:
Used in cellular reproduction or used as a template to make RNA.
◉ RNA (structure & function).
Answer: Structure:
Composed of phosphate, ribose, A/U/C/G bases, RNA is single
stranded.
A-->U or C-->G
Function:
Used in protein synthesis.
,◉ ATP.
Answer: -Adenosine triphosphate
-An organic substance composed of 3 phosphates, ribose, and
adenine, it has a modified RNA nucleotide
-A form of energy stored in covalent bonds
-Powers cellular activities; broken bonds release immediately usable
energy
-Note: "~" = high energy bond
ATP --> ADP + Pi
(adenosine diphosphate) (inorganic phosphate)
◉ The Cell.
Answer: The basic structural and functional unit of the body which
can perform all basic life functions.
◉ Cell Membrane.
Answer: Also referred to as Plasma membrane or Plasmalemma, it is
composed of a phospholipid bilayer, cholesterol, membrane
proteins, membrane carbohydrates, and microvilli.
◉ Phospholipid Bilayer.
,Answer: -Contains a phosphate head group (hydrophilic)
-Contains FA tails (hydrophobic)
-Divides ICF (intracellular fluid/ inside the cell) from ECF
(extracellular fluid/ outside the cell)
◉ Cholesterol.
Answer: Scattered throughout the membrane, it adds stability to the
plasmalemma.
◉ Membrane Proteins.
Answer: 2 Types:
i) Integral Proteins - Within the membrane, therefore have a
hydrophobic region. Some extend across the plasma (called
transmembrane proteins).
ii) Peripheral Proteins - Attached to either surface region of integral
proteins.
Functions:
-Enzymes
-Transporters
-Channels
-Receptors
-Anchors
, -Identity markers (for immune system)
◉ Membrane Carbohydrates.
Answer: Only on the outer surface, they bind to proteins
(glycoproteins) or lipids (glycolipids).
Functions:
i) Cell recognition Ex. Egg and sperm
ii) Anchor cells together
◉ Microvilli.
Answer: Small projections of the cell membrane that functions to
increase surface area. Best seen on cells of small intestine and
kidney.
◉ Fluid-Mosaic Model.
Answer: Fluid--> Constituents can move around (phospholipids and
some proteins).
Mosaic--> Proteins dot the surface like tiles in a mosaic.
◉ Cytoplasm.
Answer: The area inside the cell membrane and outside of the
nucleus.