Pob 1 struggling topics Flashcards
Ionic bonds
form when one atom donates one or more electron to another
Covalent bond
when 2 atoms share an electron pair
Valence
atoms number of bonds it can form
How many covalent bonds Carbon can make
4 since its valence number is 4
What are hydrogen bond?
are non-covalent bonds formed between electropositive hydrogen and electronegative atom
Structural isomers
have the same molecular formula but different connectivity between atoms
slide 27
Geometric isomers
single bonds make tetrahedra and can rotate
double bonds impose a flat structure: these bonds do not rotate
Cis isomer
has the larger functional groups on the same side
slide 29
Trans isomer
larger functional groups are on opposite sides
slide 29
C=C
molecules can have multipe C=C double bonds: each one could be cis or trans
Chiral
carbon bonded to 4 different functional groups
when stereoisomers occur
How disaccharides form
loss of water (dehydration) to form glycoside linkage
What are the components of a nucleotide
Phosphate groups, sugar (pentose), and nitrogenous base
Exam 3 q3: Which of the following statements about coordinated responses in communication in multicellular organisms is correct?
A. The endocrine system is slow and targets few cells
B. The nervous system is slow and targets many cells
C. The endocrine system is fast and targets a few cells
D. The nervous system is fast and targets a few cells
D= The nervous system is fast and targets a few cells
A= Incorrect:The endocrine system is slow and targets few cells
Exam 3 q6: Why are cattle able to survive on a diet consisting almost entirely of plant material?
E=They have cellulose-digesting, symbiotic microorganisms in chambers of their stomachs
D=Incorrect: Cattle saliva has enzymes capable of digesting cellulose
Exam 3 q9: What would be expected if the amount of interstitial fluid surrounding the capillary beds of the lungs were to increase significantly?
C= The amount of oxygen entering the circulation from the lungs would decrease.
B=Incorrect: The amount of oxygen entering the circulation from the lungs would increase.
Exam 3 q10: Why is gas exchange more difficult for aquatic animals with gills than for terrestrial animals
B= Water contains much less O2 than air per unit volume.
C= Incorrect: Gills have less surface area than lungs
Exam 3 q16: Which of the following differentiates T cells and B cells?
C= T cells but not B cells can directly attack and destroy invading pathogens.
B= Incorrect: Only B cells are produced from stem cells of the bone marrow
Exam 3 q20: The advantage of excreting wastes as urea rather than as ammonia is that
B. Urea is less toxic than ammonia
Incorrect: E. Less nitrogen is removed from the body.
Exam 3 q25: The endocrine system and the nervous system are structurally related. Which of the following cells best illustrates this relationship?
C. A neurosecretory cell in the hypothalamus
Incorrect: D. A brain cell in the cerebral cortex
Exam 3 q26: Which of the following hormone actions will occur when more energy is required by a human?
B. Blood glucagon increases
Incorrect: C. Both insulin and glucagon increase.
Exam 3 q27: Which of the following statements about the hypothalamus is incorrect?
A. It functions as an endocrine gland.
B. It is part of the central nervous system.
C. It is subject to feedback inhibition by certain hormones.
D. It secretes tropic hormones that act directly on the gonads.
E. Its neurosecretory cells terminate in the posterior pituitary.
D. It secretes tropic hormones that act directly on the gonads.
Incorrect: A. It functions as an endocrine gland.
Exam 2 q29: Action potentials move along axons
A. More slowly in axons of large than in small diameter.
B. By the direct action of acetylcholine on the axonal membrane.
C. By activating the sodium-potassium “pump” at each point along the axonal membrane.
D. More rapidly in myelinated than in non-myelinated axons.
E. By reversing the concentration gradients for sodium and potassium ions
D. More rapidly in myelinated than in non-myelinated axons.
Incorrect:C. By activating the sodium-potassium “pump” at each point along the axonal membrane.
Exam 3 q32: The steps below refer to various stages in transmission at a chemical synapse:
1. Neurotransmitter binds with receptors associated with the postsynaptic membrane.
2. Calcium ions rush into the neuron’s cytoplasm.
3. An action potential depolarizes the membrane of the axon terminal.
4. The ligand-gated ion channels open.
5. The synaptic vesicles release neurotransmitters into the synaptic cleft.
C. 3 → 2 → 5 → 1 → 4
Incorrect: D. 4 → 3 → 1 → 2 → 5
Exam 3 q33: When several EPSPs arrive at the axon hillock from different dendritic locations, depolarizing the
postsynaptic cell to threshold for an action potential, this is an example of
B. Spatial summation.
Incorrect: E. An action potential with an abnormally high peak of depolarization.
Exam 3 q1.1 Table
Look at table (Obese, Thin. Obese, Same)
Exam 3 q2.1 Table
Look at table (normal, normal, high. high, high, normal)