Answer the following question given this paragraph: the conditions, amino acids can act as either acids or bases, which means that proteins act as buffers. The pH at which an amino acid exists as the zwitterion is called theisoelectric point (pI). The amino acids in a protein are linked together by peptide bonds. Protein chains containing 10 or fewer amino acids are usually referred to as peptides, with a prefix such as di- or tri- indicating the number of amino acids. Chains containing more than 50 amino acid units are referred to as proteins orpolypeptides. Proteins are classified globular or fibrous, depending on their structure and resulting solubility in water. Globular proteins are nearly spherical and are soluble in water; fibrous proteins have elongated or fibrous structures and are not soluble in water. Protein molecules can have as many as four levels of structure. The primary structure is the sequence of amino acids in the chain. The secondary structure is the arrangement of adjacent atoms in the peptide chain; the most common arrangements are -helices or -pleated sheets. The tertiary structureis the overall three-dimensional shape of the molecule that results from the way the chain bends and folds in on itself. Proteins that consist of more than one chain have quaternary structure, which is the way the multiple chains are packed together. Four types of intramolecular and intermolecular forces contribute to secondary, tertiary, and quaternary structure: (1) hydrogen bonding between an oxygen or a nitrogen atom and a hydrogen atom bound to an oxygen atom or a nitrogen atom, either on the same chain or on a neighboring chain; (2) ionic bondingbetween one positively charged side chain and one negatively charged side chain; (3) disulfide linkages between cysteine units; and (4) dispersion forcesbetween nonpolar side chains. Because of their complexity, protein molecules are delicate and easy to disrupt. Adenatured protein is one whose conformation has been changed, in a process called denaturation, so that it can no longer do its physiological job. A... Q: Protein chains containing 10 or fewer amino acids are usually referred to as what? Choices: - polypeptides - protons - carboxyl - peptides A:
peptides
(Question)
Answer the following question given this paragraph: Ligaments are made of tough protein fibers and connect bones to each other. Your bones, cartilage, and ligaments make up your skeletal system . Q: What is the term for tough protein fibers that connects bones to each other? Choices: - tetons - cords - muscles - ligaments A:
(Answer)
ligaments
Ques: Answer the following question given this paragraph: 30.5 Transport of Water and Solutes in Plants Water potential () is a measure of the difference in potential energy between a water sample and pure water. The water potential in plant solutions is influenced by solute concentration, pressure, gravity, and matric potential. Water potential and transpiration influence how water is transported through the xylem in plants. These processes are regulated by stomatal opening and closing. Photosynthates (mainly sucrose) move from sources to sinks through the plant's phloem. Sucrose is actively loaded into the sieve-tube elements of the phloem. The increased solute concentration causes water to move by osmosis from the xylem into the phloem. The positive pressure that is produced pushes water and solutes down the pressure gradient. The sucrose is unloaded into the sink, and the water returns to the xylem vessels. Q: Transport of water and solutes in plants water potential is a measure of the difference in potential energy between a water sample and this? Choices: - green water - dirty water - salty water - pure water A:
Ans: pure water
(Q).
Answer the following question given this paragraph: An aldehyde is a carbonyl in which the carbon atom is bonded to one carbon atom and one hydrogen atom (or two hydrogen atoms, see below). Because the hydrogen atom is so small, the partial positive charge on the carbonyl carbon is very easy for other molecules to approach, making aldehydes a particularly reactive type of carbonyl. Aldehydes are versatile reactants for a wide variety of organic syntheses. Many aldehydes also have distinctive flavors and aromas. For example, the flavor of cinnamon is primarily due to the molecule cinnamaldehyde, and vanillin is the aldehyde most responsible for the smell and taste of vanilla extract. Q: Name a carbonyl in which the carbon atom is bonded to one carbon atom and one hydrogen atom (or two hydrogen atoms). Choices: - ketone - acetylcholine - ester - aldehyde A:
(A).
aldehyde
Ques:Answer the following question given this paragraph: Mammals are endothermic vertebrates with four limbs. Examples of mammals include bats, whales, mice, and humans. Clearly, mammals are a very diverse group. Nonetheless, they share several traits that set them apart from other vertebrates. Q: How many limbs do all mammals have? Choices: - three - it varies - two - four A:

Ans:four
Question: Answer the following question given this paragraph: The atmosphere has layers. The layers correspond with how temperature changes with altitude. By understanding the way temperature changes with altitude, we can learn a lot about how the atmosphere works. Q: The layers of the atmosphere correspond with what changes with altitude? Choices: - friction - nitrogen - oxygen - temperature A:
Answer:
temperature