Exam 1 Questions
List the four main families of biomolecules
1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic Acids
Aerobic metabolism of glucose produces _________molecules of ATP while anaerobic metabolism of glucose produces _____________molecules of ATP A) 2, 30-32 B) 0, 16 C) 6, 6 D) 30-32, 2
30-32, 2
Each is an example of homeostasis EXCEPT one. Identify the exception A) Increased pressure in the aorta triggers mechanisms to lower blood pressure. B) A rise in blood calcium levels triggers the release of a hormone that lowers blood calcium levels. C) A rise in estrogen during the menstrual cycle increases the number of progesterone receptors in the uterus. D) Increased blood sugar stimulates the release of a hormone from the pancreas that stimulates the liver to store blood sugar. E) A decrease in body temperature triggers a neural response that initiates physiological changes to increase body temperature.
A rise in estrogen during the menstrual cycle increases the number of progesterone receptors in the uterus
Name the two types of physiological signals
Chemical Electrical
A gap junction forms when opposing membrane-spanning proteins called ________ on two adjacent cells unite, creating a protein channel that is capable of opening and closing
Connexins
Design a flow chart or concept map summarizing the steps of protein synthesis. Be sure to identify where in a cell each step occurs.
DNA transcription, mRNA leaves nucleus, mRNA interacts with ribosomes, RNA translation,RT proteins sent into ER for transport and modification, proteins sent to Golgi, packaged and sent to destination
Gases cannot act as signaling molecules T/F?
False
Define Wolf's Law
Form follows function
The proteins synthesized in the rough endoplasmic reticulum are then sent to the A) smooth endoplasmic reticulum for storage. B) Golgi complex for packaging. C) lysosome for modification. D) cell membrane for secretion. E) nucleus for cellular use
Golgi complex for packaging
Red blood cells are in a buffer solution with an osmolarity of 200 mOsM. The red blood cells have an osmolarity of 300 mOsM. The solution is (hypertonic, hypotonic, isotonic) to the cells. Water will move (into the cells, out of the cells, or not at all). Circle your answers
Hypotonic into the cells
Order levels of body organization from smallest to largest A) tissue B) cell C) organ D) molecule E) organism F) organ system
Molecule Cell Tissue Organ Organ system Organism
Which of the following is NOT a function of membrane proteins A) respond to extracellular molecules B) creating junctions between cells C) act as transport molecules for various solutes D) anchor or stabilize the cell membrane E) produce energy
Produce energy
Fick's Law of Diffusion is A) Rate of movement = mass X volume / time B) Rate of diffusion = distance / voltage C) Rate of diffusion = surface area X concentration gradient X membrane permeability D) Rate of movement = surface are X yards X membrane potential
Rate of diffusion = surface area X concentration gradient X membrane permeability
List 4 categories of membrane receptors
Receptor-channel G protein coupled receptor-enzyme integrin receptors
Why do some normal cells fail to respond to a chemical signal A) Chemical signals are only delivered to specific cells. B) Some cells lack the necessary receptors. C) Some cells are completely without receptors. D) Some cells are completely without ligands. E) Signal chemicals often break down before reaching a distant target.
Some cells lack the necessary receptors
Each of the following statements concerning the mitochondria are true except A) the mitochondrial cristae form the inner membrane forming separate compartments B) The matrix of the mitochondria contains metabolic enzymes involved in energy production. C) The intermembrane space plays an important role in mitochondrial ATP production. D) The mitochondria contain no DNA or RNA.
The mitochondria contain no DNA or RNA
Lipophilic ligands induce slower cellular responses than lipophobic ligands T/F
True
Saturation occurs when A) molecules are moved by the use of vesicles. B) the energy required to move molecules results from a high-energy bond. C) a group of carrier proteins is operating at its maximum rate. D) a preference of a carrier protein for a substance is demonstrated based on the differing affinities of the carrier for the substrates. E) a carrier molecule has the ability to transport only one molecule or a group of closely related molecules
a group of carrier proteins is operating at its maximum rate
The intracellular effector in chemical signaling is often A) a hormone. B) a membrane receptor molecule. C) ATP. D) a protein kinase. E) cholesterol
a protein kinase
A receptor may have multiple ligands. Receptor __________ mimic the action of a signal molecule. Receptor _____________block the signal pathway A) activator, agonist B) agonist, antagonist C) antagonist, agonist D) activator, agonist
agonist, antagonist
Essential amino acids that are used to build proteins A) exist in twenty six different configurations. B) are linked together by ionic chemical bonds in proteins. C) can be used medically for both diagnosis and treatment of diseases. D) are derived from the foods we eat and digest. E) can only be made by cells within our bodies.
are derived from the foods we eat and digest
The organic molecules known as phospholipids are key components of cell membranes and composed of which molecules A) amino acids B) nucleotides C) glycerol D) fatty acids E) both glycerol and fatty acids
both glycerol and fatty acid
When a cell reaches equilibrium it is _________ A) in homeostasis B) at neutral pH C) at steady state D) dead
dead
Caveolae and clathrin-coated pits are both used in A) endocytosis. B) exocytosis. C) phagocytosis. D) All of the answers are correct. E) None of the answers are correct
endocytosis
Large molecules are brought into cells by _____________. Large molecules leave cells through __________ A) pinocytosis, endocytosis B) endocytosis, exocytosis C) exocytosis, mitocytosis D) Both A and B
endocytosis, exocytosis
The number of mitochondria in skeletal muscle cells is ______________ adipose (fat) cells A) greater than B) less than C) equal to
greater than
Hyposmotic solutions A) have higher concentrations of solutes than hyperosmotic solutions. B) have lower concentrations of solutes than other hyposmotic solutions. C) have the same concentration of solutes as hyperosmotic solutions. D) have lower concentrations of solutes than hyperosmotic solutions. E) None of the answers are correct.
have lower concentrations of solutes than hyperosmotic solutions
All but one of the structures below are a type of cell junction. Identify the exception A) desmosomes B) tight junctions C) gap junctions D) loose junctions E) adherens junctions
loose junctions
Enzymes increase reaction rate by A) lowering the activation energy of a reaction. B) increasing the free energy in the products. C) raising the activation energy of a reaction. D) converting an endergonic reaction to an exergonic reaction
lowering the activation energy of a reaction
_________ signaling molecules bind to receptors on neighboring cells while _________ signaling molecules bind to receptors on the cells in which the signal originated
paracrine autocrine
Epithelial cells that are adapted for membrane transport of materials, such as ions and nutrients, usually have ________ on their apical surface A) mitochondria B) cilia or flagella C) microvilli D) junctional complexes E) vesicles
microvilli
Most of the ATP required to power cellular operations is produced in the A) ribosomes. B) endoplasmic reticulum. C) nucleus. D) mitochondria. E) Golgi apparatus.
mitochondria
Nucleic acids are polymers of units called A) amino acids. B) fatty acids. C) bases. D) ribose. E) nucleotides.
nucleotides
Receptors for signal pathways may be found in the ___________, the___________, or the ____________ of the cell A) mitochondria, nucleus, lysosome B) nucleus, cytosol, cell membrane C) cell membrane, Golgi apparatus, ribosome D) cytosol, endoplasmic reticulum, nucleus
nucleus, cytosol, cell membrane
Homeostasis is the ability of the body to A) prevent the external environment from changing. B) prevent the internal environment from changing. C) quickly restore changed conditions to normal. D) ignore external stimuli to remain in a state of rest. E) prevent excessive blood loss.
quickly restore changed conditions to normal
The following are types of mediated transport EXCEPT one. Identify the exception A) facilitated diffusion B) primary active transport C) simple diffusion D) secondary active transport
simple diffusion
. Match the membrane protein with its function. A. transfer signals from the extracellular environment to the cytoplasm of the cell B. form cell-to-cell connections C. bind to molecules to facilitate entry to or exit from the cell D. ligands bind to these proteins and are changed by the protein Structural proteins ____________ enzymes __________ receptors__________ transporters_________
structural proteins__B___ enzymes__A_____ receptors___D_____ transporters__C______
The law of mass balance states A) that if the amount of substance in the body is to remain constant any gain must be offset by an equal loss. B) that every action has an equal and opposite reaction C) that the total amount of energy in the universe is constant
that if the amount of substance in the body is to remain constant any gain must be offset by an equal loss
A competitive inhibitor binds to A) a region of the enzyme other than the active site. B) the active site. C) the substrate. D) the product. E) the surrounding tissue.
the active site
Energy is defined as A) doing tasks that make you tired. B) the capacity to do work. C) the light and heat from the sun. D) using glucose to synthesize ATP.
the capacity to do work
What is the smallest unit of life
the cell
Physiology if the study of A) the structure of the body. B) the tissues and organs of the body at the microscopic level. C) growth and reproduction. D) the normal function of living organisms. E) the facial features as an indication of personality.
the normal function of living organisms
Both insulin and glucagon are peptide hormones that target liver cells. The response of the target cells to each of these two hormones is opposite. This information implies that A) the two hormones bind to different cell surface receptors. B) one hormone binds to a receptor on the cell membrane and the other to an intracellular receptor. C) each of the two hormones uses a different second messenger. D) both hormones interact with receptors at the cell nucleus. E) the two hormones bind to different receptors and use a different second messenger.
the two hormones bind to different receptors and use a different second messenger
Molecules that pass through epithelial cells use the ___________route A) intercellular B) paracellular C) extracellular D) transcellular
transcellular
Chemical reactions in a living system function to A) only transfer energy from one molecule to another. B) create new energy. C) only use energy stored in a molecule. D) transfer energy from one molecule to another or use energy stored in a molecule
transfer energy from one molecule to another or use energy stored in a molecule
An ion widely important in intracellular signaling is A) sodium. B) potassium. C) calcium. D) chloride. E) cobalt.
calcium
Each amino acid differs from others in the A) number of central carbon atoms. B) size of the amino group. C) number of carboxyl groups. D) chemical structure of the R group. E) number of peptide bonds in the molecule
chemical structure of the R group
