The structure of valine, an amino acid

11 Jun The structure of valine, an amino acid

Question
The structure of valine, an amino acid, is shown. What portion of the valine
molecule is indicated by the shaded area? Select one:
a. amino group
b. carbon chain
c. carboxyl group
d. R group

Question 2 Not yet answered
Points out of 5.84 Flag question Question text
Nucleotides are composed of
Select one:
a. adenosine triphosphate, pentose sugars, and phosphates.
b. DNA, ribose sugars and polypeptides. c. nitrogen-containing bases, phosphates, and peptides.
d. phosphates, pentose sugars, and nitrogen-containing bases.

Question 3 Not yet answered
Points out of 5.84 Flag question Question text
What are the primary constituents of cell membranes?
Select one:
a. carbohydrates
b. lipids
c. minerals
d. proteins

Question 4 Not yet answered
Points out of 5.84 Flag question Question text
Which of the following is an organic catalyst and usually a protein?
Select one:
a. ATP
b. coenzyme
c. enzyme
d. substrate

Question 5 Not yet answered
Points out of 5.84 Flag question Question text Which of the following cell organelles is the site of the citric acid cycle?
Select one:
a. Golgi apparatus
b. mitochondria
c. nucleus
d. ribosome

Question 6 Not yet answered
Points out of 5.84 Flag question Question text
What is the degradation product of heme?
Select one:
a. bile pigment
b. globin
c. iron
d. porphyrin

Question 7 Not yet answered
Points out of 5.84 Flag question Question text
During photosynthesis, which of the following happens?
Select one:
a. Carbon dioxide is reduced to glucose.
b. Chloroplasts convert solar energy to ADP.
c. Hydrogen atoms reduce water to glucose.
d. Water is hydrolyzed.

Question 8 Not yet answered
Points out of 5.84 Flag question Question text Which of these are the photosynthetic organs of a plant?
Select one:
a. cones
b. fruits
c. leaves
d. seeds

Question 9 Not yet answered
Points out of 5.84 Flag question Question text
Which of these is an end product of photosynthesis?
Select one:
a. ATP
b. carbon dioxide
c. glucose
d. water

Question 10 Not yet answered
Points out of 5.84 Flag question Question text
What is the total number of ATP molecules produced by the citric acid cycle?
Select one:
a. 2
b. 4
c. 16
d. 256

Question 11 Not yet answered
Points out of 5.84 Flag question Question text In cellular respiration, what percentage of the available energy is transferred
from glucose to ATP?
Select one:
a. 17%
b. 28%
c. 39%
d. 63%

Question 12 Not yet answered
Points out of 5.84 Flag question Question text
Based on their characteristics, mitochondria could be evolutionary remnants of
which type of microorganism?
Select one:
a. bacteria
b. fungi
c. protozoa
d. virus

Question 13 Not yet answered
Points out of 5.84 Flag question Question text
In cellular respiration, what is the end product of chemiosmosis?
Select one:
a. ATP
b. glucose
c. NADH
d. pyruvic acid

Question 14 Not yet answered
Points out of 5.84 Flag question Question text The primary cell wall of plants is composed of which of the following?
Select one:
a. cellulose
b. chitin
c. lignin
d. phospholipid

Question 15 Not yet answered
Points out of 5.84 Flag question Question text
What unique structural property of cellulose makes it largely indigestible by
humans?
Select one:
a. addition of chitin, another structural polysaccharide
b. alternating positioning of oxygen atoms in linked glucose
c. branched chains of linked glucose
d. covalent bonding between glucose units, providing extra stability

Question 16 Not yet answered
Points out of 5.84 Flag question Question text
How do peripheral proteins play a role in the plasma membrane?
Select one:
a. They assist in movement of molecules into the intracellular space.
b. They allow ions to flow directly through the membrane.
c. They bind with glycoproteins for cell recognition in immune responses.
d. They bind with a carrier protein to facilitate membrane transport.

Question 17 Not yet answered
Points out of 5.84 Flag question Question text At the end of meiosis I, how many chromosomes from each homologous parental
pair does one daughter cell contain?
Select one:
a. 1
b. 2
c. 3
d. 4

Question 18 Not yet answered
Points out of 5.84 Flag question Question text
In meiosis, crossing-over of genetic material between two non-sister chromatids
occurs during
Select one:
a. anaphase I.
b. metaphase II.
c. prophase I.
d. telophase II.

Question 19 Not yet answered
Points out of 5.84
Flag question Question text
In the phase of mitosis depicted in the figure, which of the following is occurring? Select one:
a. Chromatids are crossing over.
b. Chromosomes are aligning on the plates.
c. Daughter cells are being formed.
d. Sister chromatids are separating.

Question 20 Not yet answered
Points out of 5.84
Flag question Question text
In the representation of a DNA molecule shown below, what parts of the
nucleotides are indicated by the colors red, green, blue, and yellow? Select one:
a. nitrogenous base
b. pentose sugar
c. phosphate
d. ribose sugar

Question 21 Not yet answered
Points out of 5.84
Flag question Question text
Using the Punnett square, what is the phenotypic ratio of tall plants to short
plants? Select one:
a. 1:1
b. 2:1
c. 3:1
d. 1:3

Question 22 Not yet answered
Points out of 5.84 Flag question Question text
Which of the following causes of mutations occurs when nucleotide pairs are
replicated?
Select one:
a. errors in replication
b. mutagens
c. transposons
d. gene expression

Question 23 Not yet answered
Points out of 5.84 Flag question Question text In the following mutation the letter “C” was deleted from the sequence of
codons. Instead of reading “THE CAT ATE THE RAT” the sequence reads “THE ATA
TET HER AT.” Which of the following types of mutation is this?
Select one:
a. deletion mutation
b. frameshift mutation
c. point mutation
d. protein mutation

Question 24 Not yet answered
Points out of 5.84 Flag question Question text
Which of the following is an estimate of the number of pairs of DNA bases in the
human genome?
Select one:
a. 300,000 pairs
b. 5.8 million pairs
c. 3.2 billion pairs
d. 6.4 trillion pairs

Question 25 Not yet answered
Points out of 5.84 Flag question Question text
Which type of bacteria is produced by biotechnology to express a cloned gene?
Select one:
a. aerobic
b. pathogenic
c. peritrichous
d. transgenic

Question 26 Not yet answered
Points out of 5.84
Flag question Question text
In this illustration of the stem of a plant, the arrow points to which structure? Select one:
a. auxiliary bud
b. node
c. petiole
d. terminal bud

Question 27 Not yet answered
Points out of 5.84 Flag question Question text
Which type of root is used by certain plants for food storage?
Select one:
a. adventitious
b. fibrous
c. pneumatophore
d. tap

Question 28 Not yet answered
Points out of 5.84 Flag question Question text
Which of the following processes involves evaporation of water from the leaves?
Select one:
a. osmosis
b. respiration
c. translocation
d. transpiration

Question 29 Not yet answered
Points out of 5.84 Flag question Question text According to the cohesion-tension model, how does xylem transport work in
plants?
Select one:
a. Tension created by atmospheric pressure pushes water up the xylem.
b. Tension created by transpiration in the leaves pulls water along the xylem.
c. Water entering the root cells creates negative pressure that pushes water up
the xylem.
d. Water is actively transported up the xylem by gravity.

Question 30 Not yet answered
Points out of 5.84
Flag question Question text
Which of the following types of tropism is exhibited by the plant shown in the
photograph? Select one:
a. negative gravitropism
b. negative phototropism
c. positive phototropism
d. positive gravitoprism

Question 31 Not yet answered
Points out of 5.84 Flag question Question text
Which plant hormone facilitates ripening of fruits?
Select one:
a. abscisic acid
b. auxin
c. ethylene
d. gibberellin

Question 32 Not yet answered
Points out of 5.84
Flag question Question text
Referring to the diagram, what is the correct order of labeling for the boxes (1-4)
depicting alternation of generations in flowering plants? Select one:
a. (1) meiosis, (2) mitosis, (3) fertilization, (4) mitosis
b. (1) meiosis, (2) mitosis, (3) mitosis, (4) meiosis
c. (1) mitosis, (2) meiosis, (3) fertilization, (4) mitosis
d. (1) mitosis, (2) meiosis, (3) meiosis, (4) mitosis Question 33 Not yet answered
Points out of 5.84 Flag question Question text
In plant reproduction, what is the eudicot structure that provides nutrition to the
embryo?
Select one:
a. cotyledon
b. hypocotyl
c. plumule
d. radicle

Question 34 Not yet answered
Points out of 5.84 Flag question Question text Which of the following parts of a flower protect the bud as the flower develops?
Select one:
a. anthers
b. ovaries
c. petals
d. sepals

Question 35 Not yet answered
Points out of 5.84 Flag question Question text
An animal exhibits the following characteristics: tentacles, radial symmetry, and
incomplete digestive tract. This animal would be classified in which phylum?
Select one:
a. Cnidaria
b. Platyhelminthes
c. Porifera
d. Rotifera

Question 36 Not yet answered
Points out of 5.84
Flag question Question text
According to the cladogram shown, what two characteristics distinguish lizards
from gorillas? Select one:
a. an amniotic membrane and hair
b. bipedalism and a tail
c. hairlessness and a tail
d. jaws and lungs

Question 37 Not yet answered
Points out of 5.84
Flag question Question text
In the context of evolution, which type of selection is depicted in the graph? Select one:
a. directional selection
b. disruptive selection
c. natural selection
d. stabilizing selection

Question 38 Not yet answered
Points out of 5.84 Flag question Question text
According to the Hardy-Weinberg principle, allele frequencies in a gene pool will
remain at equilibrium as long as there is
Select one:
a. interbreeding between populations.
b. frequent mutation.
c. genetic drift.
d. random mating.

Question 39 Not yet answered
Points out of 5.84 Flag question Question text Spores are found in which part of a mushroom?
Select one:
a. hyphae
b. lamellae
c. pileus
d. stipe

Question 40 Not yet answered
Points out of 5.84 Flag question Question text
Which of the following types of mammal has a cloaca?
Select one:
a. marsupial
b. monotreme
c. Placental
d. Testudinata

Question 41 Not yet answered
Points out of 5.84 Flag question Question text
The blastopore develops into the anus in which of these invertebrates?
Select one:
a. cockroach
b. earthworm
c. sea cucumber
d. squid

Question 42 Not yet answered
Points out of 5.84 Flag question Question text According to the replacement model, where did the Homo sapiens in Europe
migrate from?
Select one:
a. Africa
b. Asia
c. Europe
d. North America Question 43 Not yet answered
Points out of 5.84 Flag question Question text
Which of the following human ancestors were the first to make tools?
Select one:
a. Ardipithecines
b. Australopithecines
c. Homo erectus
d. Homo habilis

Question 44 Not yet answered
Points out of 5.84 Flag question Question text
Which type of tissue lines the cavities of the human body?
Select one:
a. connective
b. epithelial
c. muscular
d. nervous

Question 45 Not yet answered
Points out of 5.84 Flag question Question text In the human body, which of these is a matrix of white fibers in connective
tissue?
Select one:
a. actin
b. collagen
c. elastic
d. myosin Question 46 Not yet answered
Points out of 5.84 Flag question Question text
Which term refers to the outermost layer of human skin?
Select one:
a. dermis
b. subcutaneous
c. epidermis
d. follicle

Question 47 Not yet answered
Points out of 5.84 Flag question Question text
In the human respiratory system, exchange of oxygen and carbon dioxide occurs
in the
Select one:
a. alveoli.
b. bronchi.
c. bronchioles.
d. trachea.

Question 48 Not yet answered
Points out of 5.84 Flag question Question text In human reproduction, nutrient-rich blood is transported from the placenta to
the fetus by the
Select one:
a. foramen ovale.
b. inferior vena cava.
c. umbilical artery.
d. umbilical vein.

Question 49 Not yet answered
Points out of 5.84 Flag question Question text
Which of the following female reproductive organs produces oocytes?
Select one:
a. cervix
b. ovaries
c. oviducts
d. uterus

Question 50 Not yet answered
Points out of 5.84 Flag question Question text
A typical human somatic cell contains how many chromosomes?
Select one:
a. 22
b. 23
c. 46
d. 47

Question 51 Not yet answered
Points out of 5.84 Flag question Question text What must primary mRNA undergo to become mature mRNA?
Select one:
a. processing provided by tRNA molecules
b. processing to remove introns and join exons
c. processing to remove exons and join introns
d. translation into codon of amino acids

Question 52 Not yet answered
Points out of 5.84 Flag question Question text
The addition of a poly-A tail and a guanine cap to a primary mRNA exemplifies
which level of gene control in eukaryotes?
Select one:
a. transcriptional
b. post-transcriptional
c. translational
d. post-translational

Question 53 Not yet answered
Points out of 5.84
Flag question Question text
In the food web shown in the figure, which of the following are the primary
consumers? Select one:
a. bald eagle and osprey
b. phytoplankton, submerged aquatic vegetation, and vegetation
c. small planktivorous fish, benthic invertebrates, herbivorous ducks, geese and
mute swans
d. gulls, wading birds, large piscivorous fish, sea ducks, and tundra swan

Question 54 Not yet answered
Points out of 5.84 Flag question Question text
Which of the following is the order of energy flow within an ecosystem?
Select one:
a. decomposers ? consumers ? producers
b. producers ? consumers ? decomposers
c. producers ? decomposers ? carnivores
d. decomposers ? producers ? consumers

Question 55 Not yet answered
Points out of 5.84 Flag question Question text
In the ocean, coral reefs are found in which zone?
Select one:
a. abyssal
b. bathypelagic
c. epipelagic
d. mesopelagic

Question 56 Not yet answered
Points out of 5.84 Flag question Question text Of Earth’s terrestrial biomes, which one is hot in the summer, cold in the winter,
gets moderate annual precipitation, and has good soil for agriculture?
Select one:
a. grasslands
b. shrublands
c. taiga
d. tundra

Question 57 Not yet answered
Points out of 5.84 Flag question Question text
Which protists are responsible for causing red tide?
Select one:
a. diatoms
b. dinoflagellates
c. flagellates
d. sporozoans

Question 58 Not yet answered
Points out of 5.84 Flag question Question text
Which of the following is a density-dependent regulating factor on the population
of a community?
Select one:
a. availability of space
b. competition
c. temperature range
d. water supply

Question 59 Not yet answered
Points out of 5.84 Flag question Question text Which type of learning occurs when a dog stops eating butterflies because he
gets sick every time he eats one?
Select one:
a. classical conditioning
b. operant conditioning
c. unconditioned response
d. imprinting

Question 60 Not yet answered
Points out of 5.44 Flag question Question text
To communicate the location of a food source, a honey bee returns to its hive and
performs a dance while the other bees gather around and touch it with their
antennae. By touching the returning bee with their antennae, what form of
communication are the bees exhibiting?
Select one:
a. auditory
b. chemical
c. tactile