Biology – Multiple Choice Questions (MCQ) with Answers – Part 1

Biology Science Multiple Choice Questions Part 1 Eduhyme

Biology as the scientific study of living things is a relatively recent development. The term has been in use since the early 1800s to describe the study of living organisms. Basically, an organism is a living thing that is highly organized. By this we mean that an organism has a high degree of Biological Order, a very organized pattern.

This article is for people who want to get acquainted with the concepts of basic biology. It can serve as a supplemental text in a classroom, tutored, or home-schooling environment. It should also be useful for career changers who need to refresh their knowledge of the subject.

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This article (Part 1) work contains an abundance of practice quiz, test, and exam questions. The answers are listed in the end of the article.

1. An organism is best described as:

(a) A collection of body structures
(b) A group of related body functions
(c) Any highly organized thing
(d) A living thing with a high degree of order

2. The structure of an organism is:

(a) The entire program of function it carries out
(b) The arrangement or pattern built up from its component parts
(c) The highly disordered sum of all important body parts
(d) The body parts which do not seem to fit together very well

3. Anatomy is:

(a) Body structure and the study of body structures
(b) Body function and the study of body functions
(c) The study of both body structure and body function
(d) Seldom considered whenever body structures are being studied

4. Anatomy differs from physiology in that:

(a) Only physiology occurs in living things
(b) Anatomy occurs in both living and dead organisms (not rotted away)
(c) Physiology looks at the nature of body structures
(d) Anatomy only occurs in dead things

5. Biological Order:

(a) Explains the occurrence of disease and injury
(b) Represents a particular pattern associated with living things
(c) Does not really apply to the regulation of body temperature or blood sugar
(d) Often prevents the body from responding to changes in the environment

6. An S-shaped curve followed over time generally indicates:

(a) Lack of homeostasis
(b) Biological Disorder in the external environment
(c) A heavy intensity of environmental changes
(d) The maintenance of some body structure or function within its normal range

7. Biological Disorder is usually tied to:

(a) The creation of a particular pattern associated with living things
(b) A healthy and disease-free state
(c) Breaking of a particular pattern associated with living things
(d) Normal body structure and function

8. Ecology is best defined as:

(a) The removal of diseased and damaged plants and animals from the environment
(b) Study of the relationships between different organisms and their environment
(c) The wide occurrence of Biological Disorder within the external environment
(d) A complete lack of association between different organisms and their environment

9. Natural History essentially approaches Biological Order by:

(a) Naming and classifying newly discovered organisms
(b) Testing a formal hypothesis
(c) Applying the experimental method in a consistent manner
(d) Conducting experiments on living organisms and reaching conclusions from the results

10. Homeostasis:

(a) Does not usually exist in healthy individuals
(b) Represents a ‘‘control of sameness’’ or relative constancy of the body’s internal environment
(c) Is basically the same thing as ecological relationships
(d) Was extensively studied and defined by Aristotle

11. A level of biological organization represents:

(a) Some level of complexity below an organism
(b) A particular layer within an Ancient Egyptian pyramid
(c) A certain amount of size and complexity of body structures, along with the inter-relationships between them and various non-body structures
(d) An almost complete lack of Biological Order

12. The lowest living level of biological organization is:

(a) The organelle
(b) The cell
(c) Several types of subatomic particles
(d) The ecosystem

13. The chemical level of organization includes:

(a) Organelles, cells, and communities
(b) Subatomic particles, atoms, and organs
(c) Atoms, molecules, and subatomic particles
(d) Every living level of biological organization

14. The cell nucleus represents the:

(a) Organelle level
(b) Tissue level
(c) Organ system level
(d) Molecule level

15. A molecule is a combination of two or more atoms held together by:

(a) Chemical bonds
(b) Genes
(c) Hydrocarbon fragments
(d) Electron–proton connections

16. A tissue is best defined as:

(a) The smallest living level of biological organization
(b) A collection of similar cells, plus the intercellular material between them
(c) The intercellular material between cells, and not the cells themselves
(d) A collection of similar cells, not including anything else

17. A collection of two or more organs, which together perform some complex body function:

(a) Organism
(b) Tissue
(c) Organ system
(d) Population

18. Snowshoe hares, bobcats, and arctic foxes all living in the same cold northerly area make up:

(a) A population
(b) A community
(c) An organ system
(d) An ecosystem

19. An ecosystem:

(a) Exists at a level below the community
(b) Only focuses upon the members of a particular population
(c) Includes non-living factors in the physical environment
(d) Never can be more complex than the organisms it contains

20. Ecological relationships are similar to homeostasis in that they:

(a) Can always be diagrammed in an S-shaped pattern
(b) Represent a relative constancy of the mammal’s internal environment
(c) Are restricted to the organism level and below
(d) Maintain a rough balance or equilibrium over time

21. Cosmic Order is best described as:

(a) Just another version of Biological Order
(b) A pattern of organization that occurs within the Universe
(c) Lack of any apparent organizing framework throughout the Cosmos
(d) Giant clouds of dust and gas in outer space

22. The Dawn of Life probably:

(a) Occurred before the surface of Planet Earth began to cool and rain fell
(b) Prevented evolution from progressing any farther
(c) Started Biological Order as we know it
(d) Happened only 10 million years ago

23. A heavy rain falls. Overnight, a dry, parched field becomes a swampy area behind your house. The next night, you hear thousands of frogs loudly croaking. If you lived before the time of the scientist Francesco Redi, you would likely conclude that:

(a) Alien frogs dropped out of the sky during the rainstorm!
(b) The frogs appeared suddenly in the usually dry field by spontaneous generation
(c) The frogs mutated from micro-organisms
(d) ‘‘Survival of the fittest’’ was at work

24. Biogenesis is the theory that:

(a) Living organisms are only produced from other living organisms
(b) Dead animals can give rise to living ones
(c) Sometimes plants can change into animals, and vice versa
(d) Life first arose from a primordial soup

25. ‘‘How did the very first life come into being on our planet?’’ According to the chapter, your answer to this question would be that:

(a) Ancient dinosaurs changed back into primitive micro-organisms
(b) The Ice Age froze everything solid, but then living things thawed out
(c) Natural sources of energy (such as lightning and hot lava) sparked a fundamental change in the primordial soup of complex organic compounds within ancient oceans
(d) Boiling hot lava fields changed automatically into primitive bacteria cells

26. These help provide the first solid evidence of life within the fossil record:

(a) Stromatolites
(b) Phagocytes
(c) Fine particles of sediment
(d) The bones of jawless fishes

27. Multicellular organisms:

(a) Probably evolved into unicellular ones
(b) Are generalists for the processes of life
(c) Were the likely descendants of unicellular organisms
(d) Only occasionally contain eukaryote cells

28. According to the impact hypothesis, the dinosaurs became extinct because:

(a) Jungles took over too much of the planet, thereby destroying dinosaur habitat
(b) The Earth cooled and dried out, due to a change in the tilt of its axis
(c) A huge comet or asteroid hit the Earth with such force that it created a massive cloud of dust and debris in the atmosphere
(d) The heat produced by the impact of a fiery comet melted both the North and South Poles

29. The Cenozoic Era:

(a) Is often nicknamed ‘‘The Age of Giant Amphibians’’
(b) Has alternatively been called ‘‘The Age of the Dinosaurs’’
(c) Occurred when the mammals replaced the dinosaurs as the dominant organisms on our planet
(d) Was finished long before human beings walked the Earth

30. According to Charles Darwin’s version of the Theory of Evolution:

(a) The fossil record strongly suggests that simpler organisms appeared after larger, more complex organisms
(b) Species competing for the same available resources in the environment went through a process of natural selection over time
(c) The strange animals of the Galapagos Islands were not fully adapted to their ecosystem
(d) A particular pattern of Biological Order has nothing whatsoever to do with the successful adaptation of a particular species to its environmen

31. Chemical bonds are:

(a) Ways in which Biological Disorder is promoted
(b) The means by which plants grow without need for any energy
(c) Chemical linkages that serve as temporary storers of potential energy
(d) Always due to a net loss of outermost electrons between different atoms

32. The four major types of chemical body-builders identified in this chapter are: 72 PART 2 Universal Building Blocks of Life 2, Web

(a) Proteins, lipids, glucose, and benzene
(b) Lipids, fats, proteins, and carbohydrates
(c) Nucleic acids, inorganic salts, proteins, and lipids
(d) Carbohydrates, proteins, lipids, and nucleic acids

33. DNA and RNA molecules:

(a) Are nucleic acids found in all living organisms
(b) May help build proteins only in certain plants and fungi
(c) Are both located as sections of genes within cell nuclei
(d) Neither help nor hinder the synthesis of cell proteins

34. Kinetic energy:

(a) Represents free energy that is immediately available to do work
(b) Is basically the same thing as potential energy
(c) Is seldom useful for animals, just for green plants
(d) Is the form of energy locked up in the foods humans eat

35. Anabolism and catabolism differ in that:

(a) Anabolism is synthesis, whereas catabolism is breakdown
(b) Catabolism is synthesis, whereas anabolism is breakdown
(c) One involves only organic molecules; the other, only inorganic molecules
(d) Anabolism involves splitting of ATP, but catabolism never does

36. The overall equation for photosynthesis reveals that:

(a) Both oxygen and carbon dioxide are consumed, while H2O is released
(b) Glucose and CO2 are the ultimate products
(c) Sunlight provides the energy to produce carbon dioxide
(d) Carbon dioxide and water are the inputs, glucose and oxygen the outputs

37. The biosphere:

(a) Counterbalances the oxygen consumption of plants with carbon dioxide released from animals
(b) Represents the portion of planet Earth supporting living organisms within ecological systems
(c) Has no need for photosynthesis, as long as the sun is still shining
(d) Utilizes the blue-green algae as its sole free-energy source

38. In heterotrophs:

(a) Organic foodstuffs are consumed to obtain fuel molecules for ATP production
(b) Glycolysis is always the sole source of free energy for metabolism
(c) Energy from sunlight is utilized to agitate the electrons in chlorophyll
(d) ATP is split by ATPase enzyme, thereby consuming too much free energy

39. Under anaerobic conditions, 1 molecule of eaten glucose:

(a) Ultimately results in 2 molecules of lactic acid
(b) Immediately enters the Krebs cycle
(c) Results in a total of 38 ATP molecules released for cell work
(d) Provides free electrons for the cristae

40. These cellular reactions occur only within the mitochondria:

(a) Photosynthesis by activation of chlorophyll
(b) Both glycolysis and aerobic respiration
(c) Aerobic respiration, Krebs cycle, and electron transport system
(d) Calvin and Krebs cycles in heterotrophs

41. The word, cell, comes from the Latin for:

(a) Crabs
(b) Mice
(c) Little people
(d) A chamber

42. The Modern Cell Theory:

(a) Explains that the cell is the basic unit of all living things
(b) Holds that, while cells are important, one must seek better explanations of anatomy and physiology at a different level of biological organization
(c) Was not supported by drawings of tissues viewed through a microscope
(d) Supports the concept that cell abnormality has no relationship to disease

43. An organelle always lacking from a prokaryote cell (such as a bacterium):

(a) Ribosome
(b) ER
(c) Mitochondrion
(d) Nucleus

44. Organelles that store digestive enzymes:

(a) Lysosomes
(b) Mitochondria
(c) Nuclear membranes
(d) Microtubules

45. ER:

(a) Stands for ‘‘Emergency Reserves’’ within cells
(b) Is a complex network of flattened sacs that circulates materials throughout the cell
(c) Always has ribosomes attached to its surface
(d) Has no known function within most cells

46. Codons:

(a) Consist of particular chains of amino acids within proteins
(b) Are not found within chromatin
(c) Are chemical code words contained in genes
(d) Essentially play the same roles as peptide bonds

47. During transcription:

(a) Messenger RNA makes a copy of exposed DNA bases
(b) Transfer RNA matches up with mRNA
(c) Peptide bonds are created by linking nitrogen-containing bases together
(d) A protein is manufactured from raw cellular materials

48. The cell membrane is described as selectively permeable, because:

(a) All types of particles are able to freely enter and leave the cell
(b) Certain particles are allowed to pass through it, while others are blocked
(c) Millions of tiny ions constantly cross cell boundaries
(d) No objects are allowed to permeate it

49. The overall movement of oxygen molecules from a high O2 concentration in the extracellular fluid, to a lower O2 concentration in the intracellular fluid is called:

(a) Simple diffusion
(b) Osmosis
(c) Facilitated diffusion
(d) Electrolyte imbalance

50. The longest portion of the Cell Cycle, during which protein synthesis and duplication of chromosomes occurs is known as:

(a) Daughter cell cleavaging
(b) Interphase
(c) Mitosis
(d) Normal cell stimulation by carcinogens

51. Taxonomy essentially involves:

(a) Study of surgical techniques for operating upon animals
(b) Searching for general rules or laws for classifying organisms
(c) Removing harmful species from particular ecosystems
(d) Teaching people about the dangers or benefits of particular health practices

52. Often considered the very first (most ancient) and simplest of all groups of organisms:

(a) Protists
(b) Fungi
(c) Plantae
(d) Animalia

53. Kingdom ____________ is the one including bacteria:

(a) Amoebae
(b) Protista
(c) Monera
(d) Wartae

54. Technical term for the ‘‘Family of Man’’:

(a) Primates
(b) Mammalia
(c) Hominids
(d) Vertebrates

55. Homo sapiens, apes, monkeys, and lemurs all belong to the ________ Order:

(a) Primate
(b) Hominid
(c) Homo
(d) Mammalia

56. You scoop up a lump of wet muck and examine it through a microscope. Tiny amoebas slowly moving through the muck can be classified into what Kingdom?

(a) Monera
(b) Protista
(c) Animalia
(d) Fungi

57. The Phylum Chordata:

(a) Includes all organisms with a slender cord or vertebral column in their backs
(b) Does not involve any mammals
(c) Chiefly encompasses the world of plants
(d) Focuses upon the fungi

58. Berry-shaped bacteria arranged together like a bunch of grapes:

(a) Streptococci
(b) Diplococci
(c) Bacilli
(d) Staphylococci

59. It is not wise to handle raw chicken, then lick your fingers, because:

(a) Chicken skin is a deadly poisonous material
(b) Septicemia is nearly inevitable
(c) Too many foreign organic compounds may be ingested
(d) Salmonella bacteria on the chicken may release endotoxins

60. The basic structure of a virus:

(a) Nucleus surrounded by a cell membrane and organelles
(b) Core of nucleic acid surrounded by a protein coat
(c) Just an envelope of DNA, nothing else
(d) Fast-moving cell with hair-like projections

61. The two major kingdoms of unicellular organisms are:

(a) Fungi and Protista
(b) Animalia and Plantae
(c) Protista and Monera
(d) Mammalia and Herbivora

62. The Theory of Endosymbiosis implies that:

(a) Gypsies were persecuted wrongly by the Nazis during World WarII
(b) Small, formerly independent prokaryote cells moved into larger host prokaryote cells and eventually evolved into organelles
(c) Modern eukaryote cells could only have arisen from ancient bacterial cells already containing nuclei
(d) Nucleated eukaryote cells lost their nuclei, becoming present-day bacteria

63. A junior high student on a field trip dips a tiny collecting bottle into the sunny water of a pond, and returns a sample to the science lab. Upon examining a drop of the pond water under a microscope, she will most likely see:

(a) Rapidly moving, green-colored Euglena
(b) Giant kelp and parasitic amoebas
(c) Slime molds infecting aquatic bacteria
(d) Brownish-colored Euglena without chloroplasts

64. This fact makes the unicellular protists stand out distinctly:

(a) They all lack a nucleus
(b) Each individual cell carries out the functions of an entire organism
(c) Certain cells are specialized to perform particular limited functions
(d) They cannot reproduce by themselves

65. Among the protists, it is the ____________ which most resemble tiny animals:

(a) Protozoa
(b) Slime molds
(c) Plantae
(d) Algae

66. Pseudopodia:

(a) May be utilized by both amoebas and slime molds for movement and feeding
(b) Never appear in the anatomy of the protists
(c) Literally translates as ‘‘root feet’’
(d) Help keep parasitic bloodsuckers from losing their grip on flesh!

67. Algae:

(a) Are all unicellular and microscopic
(b) Include giant kelp as well as diatoms
(c) Closely resemble many amoebas
(d) Can be dangerous parasites of human hosts

68. The main group of fungus-like protists:

(a) Diatoms
(b) Multicellular algae
(c) Slime molds
(d) Mold growing on stale bread

69. Protozoa are similar to most animals in that:

(a) They are autotrophic in their feeding habits
(b) Glucose and carbon dioxide are consumed during respiration
(c) They are heterotrophic in their feeding processes
(d) All types of organic and inorganic matter may be consumed

70. Symbiosis in general involves:

(a) Cell division, resulting in tissue specialized for certain body functions
(b) A condition wherein two different organisms live together, and they both benefit
(c) One organism being a host to a parasite that causes it to become ill
(d) Replacement of one organism by another more adapted to its environment

71. Saprophytic fungi:

(a) Absorb small molecules from the cells of living hosts
(b) Are not common enough to be worth studying
(c) Release enzymes that partially digest dead tissues
(d) Are named from their habit of feeding upon the sap leaking from injured trees

72. A key difference between fungi and slime molds:

(a) Some fungi are parasites of living organisms
(b) Most slime molds act as parasites of living hosts
(c) Fungi obtain nutrients by digesting and absorbing organic matter
(d) There are far more species of slime molds, than of fungi

73. The entire group of unicellular fungi:

(a) Molds
(b) Yeasts
(c) Morels
(d) Lichens

74. The fruiting body of a mushroom:

(a) Its extensive underground mycelium
(b) Spores released into the air
(c) A dense web of hyphae projecting above ground
(d) The sweet, cool part that always tastes like an apple!

75. The fungal phylum to which morel mushrooms belong:

(a) Zygomycetes
(b) Basidiomycetes
(c) Chytridiomycetes
(d) Ascomycetes

76. The basidia are important to a mushroom, since they:

(a) Directly absorb nutrient molecules from decaying organic matter
(b) Produce and hold its spores
(c) Branch extensively underground
(d) Allow the fruiting body to be efficiently removed

77. Phylum of fungi involving the union of two gametes:

(a) Ascomycetes
(b) Chytridiomycetes
(c) Zygomycetes
(d) Basidiomycetes

78. Probably the most primitive group of fungi, and the first to evolve from protists:

(a) The chytrids
(b) Ascomycetes
(c) Zooplankton
(d) Bread yeasts

79. Penicillium:

(a) Releases thick-walled zygospores
(b) A bluish-colored genus of mold that produces powerful antibacterial agents
(c) Frequently appears on lawns as groups of fairy ring mushrooms
(d) Is a typical club fungus

80. A lichen:

(a) Is a type of green plant (roughly the same thing as moss?)
(b) Exists as a symbiotic combination of fungi with algae or bacteria
(c) May be too delicate to live in harsh climates
(d) Basically is the fruiting body of an alga

81. A plant is:

(a) A multicellular organism that develops from an embryo, contains chlorophyll, and produces energy by photosynthesis
(b) Seldom found associated with fungi or animals
(c) Solely engaged in only the process of photosynthesis, nothing else
(d) A heterotrophic organism that gains most of its nutrition by feeding off the decaying bodies of others

82. The vascular plants:

(a) Typically are without any true leaves, stems, or roots
(b) Include the mosses and other moss-like plants
(c) Contain no hollow ducts within their tissues
(d) Are alternately called the tracheophytes

83. A bryophyte is technically:

(a) A vascular plant without true leaves
(b) A ‘‘tree moss plant’’
(c) Some kind of seedless plants without leaf veins
(d) Related closer to the slime molds than to other plants

84. Hepatica:

(a) Is a low-growing plant with lobed leaves resembling the liver
(b) Can be easily compared to a muscle in the lower leg
(c) Commonly grows to over 100 feet in height
(d) Usually lives on dry, wind-swept mountaintops

85. The main group of seedless vascular plants:

(a) Oak trees
(b) Mildews and slime molds
(c) Ferns with fronds
(d) Gymnosperm flowers

86. The vascular plants with ‘‘naked’’ seeds:

(a) Sperms
(b) Gymnosperms
(c) Angiosperms
(d) Ovas

87. Pine cones produce spores by the process called:

(a) Symbiosis
(b) Evolutionary adaptation
(c) Protective camouflage
(d) Meiosis

88. A cloud of pollen is really:

(a) Millions of microspores that have developed into male gametes
(b) Thousands of megaspores ready to be fertilized
(c) A pair of ovules within a female scale
(d) A female cone that exploded accidentally

89. The male reproductive organ of a flower:

(a) Carpel
(b) Stamen
(c) Stigma þ style
(d) Ovary

90. Dicots are flowering plants that:

(a) Contain only one small cup or hollow in their seeds as a beginning embryo
(b) Include corn plants, grasses, lilies, palm trees, and irises
(c) Enclose a pair of hollow embryos within each of their seeds
(d) Bloom only in the desert

91. The eumetazoans:

(a) Seldom contain tissues within their bodies
(b) Are usually incapable of mitosis
(c) Contain true body tissues formed after cell division in the embryo
(d) Are the main group of vertebrate organisms

92. Symmetry:

(a) Is a characteristic only found in the invertebrates?
(b) Provides an important example of Biological Disorder
(c) Indicates that a rough balance of body shape and size exists on either side of some dividing line
(d) Is frequently greatly reduced or absent in the larvae of many organisms

93. Mirror-image symmetry:

(a) Suggests bilateral symmetry between the right and left sides of a particular organism
(b) Essentially explains the body form of most adult jellyfish
(c) Is usually missing in the bodies of adult humans
(d) Involves the tricky business of organisms trying to deceive predators, by casting their reflections as ‘‘mirrors’’

94. By ‘‘cephalization’’ in an animal, it is meant that:

(a) The creature has only superior and inferior surfaces
(b) The features of a radiolarian are being expressed
(c) The animal cannot tell its right from its left
(d) There is a definite head end to its body, where the main collection of sensory organs are located

95. Germ layers:

(a) Represent ‘‘germs’’ (bacteria) that contaminate otherwise healthy cell ‘‘layers’’
(b) Are rarely observed in either vertebrate or invertebrate embryos
(c) Arise as rings of cells within the embryo, from which specialize tissues and organs eventually develop
(d) Occur as flat sheets of damaged cells in invertebrate adults

96. The inner skin of the embryo, from which the lining of the intestine andother major cavities develops:

(a) Gastrula
(b) Blastocele
(c) Ectoderm
(d) Endoderm

97. Coelomates:

(a) Are the only type of organisms containing an archenteron
(b) Are the only types of organisms having a central cavity surrounding their archenteron
(c) Never contain an archenteron
(d) Have solid bodies without internal cavities

98. The nematodes:

(a) Have nonsegmented bodies, complete digestive tracts, but a pseudocoelom rather than a true coelom
(b) Include the tapeworms, which have both coeloms and true body tissues
(c) Are a group of solid roundworms with no internal body cavities, whatsoever
(d) Is a small group of only a few dozen known species

99. The Echinoderms:

(a) Seldom occur outside of dense forested environments
(b) Being so soft-bodied, have left behind virtually no traces within the ancient Fossil Record
(c) May be alternately classified as bivalves
(d) Can be nicknamed as the ‘‘hedgehogs’’ of the Sea!

100. Which of the following would be a good example of ‘‘breaking symmetry’’ of a sea urchin?

(a) Slicing the animal exactly in half along its body midline
(b) Pulling out every single one of the animal’s spines
(c) Extracting all of the spines on only the left side of the urchin’s body
(d) Pulling out every other spine, all over the surface of the urchin’s body

Correct Answers –

  1. D
  2. B
  3. A
  4. B
  5. B
  6. D
  7. C
  8. B
  9. A
  10. B
  11. C
  12. B
  13. C
  14. A
  15. A
  16. B
  17. C
  18. B
  19. C
  20. D
  21. B
  22. C
  23. B
  24. A
  25. C
  26. A
  27. C
  28. C
  29. C
  30. B
  31. C
  32. D
  33. A
  34. A
  35. A
  36. D
  37. B
  38. A
  39. A
  40. C
  41. D
  42. A
  43. D
  44. A
  45. B
  46. C
  47. A
  48. B
  49. A
  50. B
  51. B
  52. A
  53. C
  54. C
  55. A
  56. B
  57. A
  58. D
  59. D
  60. B
  61. C
  62. B
  63. A
  64. B
  65. A
  66. A
  67. B
  68. C
  69. C
  70. B
  71. C
  72. C
  73. B
  74. C
  75. D
  76. B
  77. C
  78. A
  79. B
  80. B
  81. A
  82. D
  83. B
  84. A
  85. C
  86. B
  87. D
  88. A
  89. A
  90. C
  91. C
  92. C
  93. A
  94. D
  95. C
  96. D
  97. B
  98. A
  99. D
  100. C

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