Biological Molecules, Cell Membrane, and Energy Flow

A complete set of fill-in-the-blank practice flashcards covering biological molecules, plasma membrane transport, and cellular energy flow based on the lecture transcript.

Organic compounds are defined as carbon-based molecules that usually contain __________ atoms.

hydrogen

Polymers are synthesized by a __________ reaction and broken down by a hydrolysis reaction.

dehydration

Carbohydrates typically have a stoichiometric formula of $(CH_2O)_n$, where the ratio of carbon to hydrogen to oxygen is __________

$$1:2:1$$

Hexoses such as glucose, fructose, and galactose are simple sugars containing __________ carbon atoms.

$$6$$

Glucose, galactose, and fructose all share the chemical formula $\text{C}_6\text{H}_{12}\text{O}_6$, but differ structurally as __________.

isomers

The covalent bond formed between two monosaccharides during dehydration synthesis is called a __________ linkage.

glycosidic

Sucrose is a disaccharide composed of glucose and __________.

fructose

Starch is a mixture of two glucose polymers: linear amylose and branched __________.

amylopectin

The structural polysaccharide that forms a major component of tough plant cell walls and is the most abundant organic compound on Earth is __________.

cellulose

Fats, also called triglycerides, are constructed from one glycerol and three __________ acids.

fatty

Unsaturated fats contain double bonds that create __________ in their carbon chains, preventing tight packing and keeping them liquid at room temperature.

kinks

Phospholipids are described as __________ because they possess both a hydrophilic head and hydrophobic tails.

amphipathic

A widely used phospholipid found in egg yolks, soybeans, and wheat germ that acts as a food emulsifier is __________.

Lecithin

Of the $20$ amino acids required by the human body, the body can synthesize __________ nonessential amino acids, while __________ essential amino acids must be obtained from the diet.

$11$ nonessential and $9$ essential

The secondary structure of a protein includes common forms such as the alpha helix and the __________ sheet.

beta-pleated

The protein __________ is an example of quaternary structure composed of four peptides that bond together to form a functional oxygen carrier.

hemoglobin

In DNA nucleotides, adenine pairs with thymine and guanine pairs with __________.

cytosine

The type of RNA that features a three-looped structure and transports specific amino acids to the ribosome is __________.

Transfer RNA (tRNA)

The structure of the cell membrane is described by the Fluid Mosaic Model, which was put forward by Singer and Nicolson in __________.

$$1972$$

The sodium-potassium pump maintains ion concentration gradients by actively moving __________ sodium ions out of the cell and __________ potassium ions into the cell.

$3\,\text{Na}^+$; $2\,\text{K}^+$

The type of endocytosis described as 'cellular eating' where a cell engulfs a particle using pseudopodia is known as __________.

Phagocytosis

When an animal cell is placed in a hypotonic solution, water rushes into the cell causing it to swell and potentially __________.

lyse

The hydrolysis of ATP into ADP and inorganic phosphate releases approximately __________ of free energy.

$$-30.5\,\text{kJ\,mol}^{-1}$$

Enzymes act as biological catalysts that speed up chemical reactions by lowering the __________ energy barrier.

activation

A vital control mechanism where the end product of a metabolic pathway acts as an inhibitor to an enzyme early in that same pathway is called __________ inhibition.

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