Description : Axolotl larva shows: i. Neoteny and paedogenesis ii. Absence of thyroid affects metamorphosis iii. It is hemichordate
Last Answer : Axolotl larva shows: i. Neoteny and paedogenesis ii. Absence of thyroid affects metamorphosis iii. It is ... ii correct D. I, ii nad iii correct
Description : Planaria possesses high capacity of (a) metamorphosis (b) regeneration (c) alternation of generation (d) bioluminescence.
Last Answer : (b) regeneration
Description : With respect to lens development: a. the lens first appears at 27 days of gestation b. it is formed from neural crest cells c. the lens first appears as a vesicles with a single layer of ... d. Y suture is absent in the embryonic nucleus e. the adult lens is more spherical than the foetal
Last Answer : the lens first appears at 27 days of gestation
Description : In which of the following phyla, the adult shows radial symmetry while the larva has bilateral symmetry?
Last Answer : In which of the following phyla, the adult shows radial symmetry while the larva has bilateral ... Mollusca B. Cnidaria C. Echinodermata D. Annelida
Description : Silk is produced by (a) adult moth (b) cocoon (c) larva (d) both (a) and (c).
Last Answer : (c) larva
Description : The silkworm silk is the product of (a) salivary gland of the larva (b) salivary gland of the adult (c) cuticle of the larva (d) cuticle of the adult.
Last Answer : a) salivary gland of the larva
Description : Damaging stage of potato tuber month is –a) Adult b) Pupa c) Larva d) All of these
Last Answer : c) Larva
Description : Match the following columns and select the correct option. Column-I Column-II (A) Gregarious, polyphagous pest (i) Asterias (B) Adult with radial symmetry and larva with bilateral symmetry (ii) Scorpion (C) Book lungs (iii) Ctenoplana ... ) (iii) (c) (iii) (ii) (i) (iv) (d) (ii) (i) (iii) (iv)
Last Answer : (b) (iv) (i) (ii) (iii)
Description : What is the cell division process directly related to the embryonic growth ?
Last Answer : The embryonic growth depends directly on mitosis. Through this type of cell division, the zygote divides itself giving birth to a series of cells that by mitosis too compose differentiated tissues and organs until the formation of a complete individual.
Description : Tissues are constructed from many distinct cell types that perform different functions in response to signals from each other and the extracellular matrix. During tissue development and tissue regeneration, ... that stem cells undergo when they are required to generate a particular type of cell?
Last Answer : Asymmetric cell division. After asymmetric division, each of the two resulting daughter cells has a unique life course. For example, one daughter cell may differentiate into a specific cell type ( ... cell), whereas the other daughter cell may remain a stem cell with unlimited proliferative ability.
Description : After deciding to order replacement parts for ageing machinery, the buyer for a construction company examines catalogues and trade publications. The buyer is probably at which stage of the ... recognition B)product specification C)product-supplier search D)product selection E)product evauation
Last Answer : C)product-supplier search
Description : What is a disadvantage of adult stem cells over embryonic stem cells?
Last Answer : What is the answer ?
Description : Which of the following statements regarding fibroblasts and their function in wound healing are true? a. IL-1 has both inhibitory and promotional effects on fibroblast growth b. TNFa ... EGF (epithelial growth factor) has been demonstrated to accelerate epidermal regeneration in cutaneous wounds
Last Answer : Answer: a, d IL-1 appears to be important in the process of normal wound repair. IL-1 has been shown to stimulate skin fibroblast and keratinocyte growth, as well as ... that recombinant EGF enhances keratinocyte migration. EGF is also a potent chemoattractant for granulation tissue fibroblasts
Description : During regeneration, modification of an organ to other organ is known as (a) morphogenesis (b) epimorphosis (c) morphallaxis (d) accretionary growth.
Last Answer : b) epimorphosis
Description : Development of an egg without - fertilization is called (1) Gametogenesis (2) Parthenogenesis (3) Oogenesis (4) Metamorphosis
Last Answer : (2) Parthenogenesis Explanation: Parthenogenesis is a form of asexual reproduction in which growth and development of embryos occur without fertilization. In plants, parthenogenesis means development of an embryo from an unfertilized edd call.
Description : Development of an egg without fertilization is called (1) Gametogenesis (2) Parthenogenesis (3) Oogenesis (4) Metamorphosis
Last Answer : Parthenogenesis
Description : Antioxidants help a person maintain good health because they (a) prevent the vitamins deficiency. (b) prevent excessive oxidation of glucose and other carbohydrates. (c) neutralise the free radicals ... metabolism. (d) activate certain genes in the body cells which help delay the ageing process.
Last Answer : Ans:(c)
Description : The heat treatment process applied to cold formed steel parts is (A) Normalising (B) Tempering (C) Artificial ageing (D) Solution annealing
Last Answer : (D) Solution annealing
Description : Assertion : - Cockorach undergoes many moulting in their development stage. Reason : - Cockroach exhibits gradual metamorphosis.
Last Answer : Assertion : - Cockorach undergoes many moulting in their development stage. Reason : - Cockroach exhibits gradual metamorphosis. A. A B. B C. C D. D
Description : Study the given figure below and answer the question that follow important-questions-for-class-12-biology-cbse-fertilisation-pregnancy-and-embryonic-development-t-33-3 (i)Name the stage of human embryo the ... implantation in the uterus. (iv)Where are the stem cells located in this embryo? -Biology
Last Answer : (i)The stage is blastocyst. (ii) A—Trophoblast. It helps in attachment to endometrium during implantation and provides nourishment to developing embryo. (iii) Inner cell mass acts as precursor to embryo ... into ectoderm and endoderm. (iv) Stem cells are located in inner cell mass of embryo.
Description : After the blastula stage what is the following stage of the embryonic development ?
Last Answer : How is the passage from blastula to the next stage called? The blastula turns into gastrula in a process known as gastrulation.
Last Answer : How is the passage from blastula to the next stage called? The blastula turns into gastrula in a process known as gastrulation. Image Diversity: gastrula
Description : Which one of the following phyla is correctly matched with its two general characteristics? (a) Echinodermata - pentamerous radial symmetry and mostly internal fertilization (b) Mollusca - normally ... Chordata - notochord at some stage and separate anal and urinary openings to the outside.
Last Answer : (c) Arthropoda - body divided into head, thorax and abdomen and respiration by tracheae
Description : Which one of the following is the correct matching of the events occurring during menstrual cycle? (a) Proliferative phase : Rapid regeneration of myometrium and maturation of Graafian follicle (b) ... ) Ovulation : LH and FSH attain peak level and sharp fall in the secretion of progesterone
Last Answer : (b) Secretory phase : Development of corpus luteum and increased secretion of progesterone
Description : Commercial scale production of hydrogen from iron-steam reaction represented by, 3Fe + 3H2O = Fe3O4 + 4H2 , is not practised, as it is (A) A slow reaction (B) A discontinuous reaction (requiring regeneration of ... in development stage (by employing fluidised bed technique) (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Removal of outer exoskeleton is the process called a) Metamorphosis b) Ecdysis c) Paedogenesis d) Gametogenesis
Last Answer : a) Metamorphosis
Description : What did the ageing Mughal emperor Bahadur Shah Zafar do after he was declared the leader of the rebels? -History
Last Answer : He wrote letters to all the chiefs and rulers of the country to come forward and organise a confederacy of Indian states to fight the British.
Description : __________ of a material results, when its strength is increased & ductility is decreased by heating at a relatively lower temperature after cold working. (A) Solid solution hardening (B) Screw dislocation (C) Strain ageing (D) Twinning
Last Answer : (C) Strain ageing
Description : What is the cell division during the first stage of the embryonic development called ?
Last Answer : How is this stage characterized? The cell division in the first stage of the embryonic developments is called cleavage, or segmentation. In this stage, mitosis occurs from the zygote forming the new embryo.
Description : What are the cells produced in the first stage of the embryonic development called ?
Last Answer : The cells that resulted from the cleavage (the first stage of the embryonic development) are called blastomeres. In this stage the embryo is called morula (similar to a “morus”, mulberry).
Last Answer : The cells that resulted from the cleavage (the first stage of the embryonic development) are called blastomeres. In this stage the embryo is called morula (similar to a “morus”, mulberry). Image Diversity: morula
Description : During embryonic development, the establishment of polarity along anterior/posterior, dorsal/ventral or medial/lateral axis is called (a) organiser phenomena (b) axis formation (c) anamorphosis (d) pattern formation.
Last Answer : (a) organiser phenomena
Description : Cells become variable in morphology and function in different regions of the embryo. The process is (a) differentiation (b) metamorphosis (c) organisation (d) rearrangement.
Last Answer : (a) differentiation
Description : (i)Explain the events taking place at the time of fertilisation of an ovum in a human female. (ii)Trace the development of the zygote up to its implantation in the uterus. (iii)Name and draw a labelled sectional view of the embryonic stage that gets implanted. -Biology
Last Answer : (i)In humans, the fertilisation of ovum takes place in ampullary-isthmic junction of Fallopian tube. The events that occur during the process of fertilisation are: (a) The sperm reaches the ... endometrium of the uterus. This is called implantation.(iii) Blastocyst stage implants in the uterus.
Description : Correct sequence of human embryonic development is
Last Answer : Correct sequence of human embryonic development is A. Gastrocoel-Blastocoel-Neural Crest - ... . Blastocoel-Gastrucoel-Neural crest -Notochord.
Description : Which germ layer developes first during embryonic development?
Last Answer : Which germ layer developes first during embryonic development? A. Ectoderm B. Mesoderm C. Endoderm D. Both 1 and 3
Description : During embryonic development , endoskeleton and muscle develop from which germinal layer :
Last Answer : During embryonic development , endoskeleton and muscle develop from which germinal layer : A. Ectoderm B. Endoderm C. Mesoderm D. Blastopore
Description : In which stage of development the embryonic cells form the germinal layers by the movement
Last Answer : In which stage of development the embryonic cells form the germinal layers by the movement A. Morula B. Blastula C. Gastrula D. Zygote
Description : Three germ layers are formed during which stage of embryonic development :-
Last Answer : Three germ layers are formed during which stage of embryonic development :- A. Morula B. Blastula C. Gastrula D. In any two stages
Description : How are animals classified according to the germ layers present in their embryonic development ?
Last Answer : Cnidarians are diploblastic, i.e., they present only endoderm and ectoderm. With the exception of poriferans, all remaining animals are triploblastic. Poriferans do not present differentiated tissue ... not classify regarding germ layers (although sometimes they are mentioned as diploblastic).
Description : What are the four initial stages of the embryonic development ?
Last Answer : The four initial stages of the embryonic development are the morula stage, the blastula stage, the gastrula stage, and the neurula stage.
Description : What is the chorioallantois membrane present in the embryonic development of reptiles and birds ?
Last Answer : How does this membrane participate in the energetic metabolism of the embryo? The chorioallantois membrane is formed by juxtaposition of some regions of the chorion and the allantois. Since it is ... of gases between the embryo and the exterior thus making aerobic cellular respiration possible.
Description : Is the mammalian embryonic development direct or indirect?
Last Answer : In mammals the embryonic development is direct, without larval stage.
Description : Is the embryonic development in birds direct or indirect?
Last Answer : The embryonic development is direct, there is no larval stage.
Description : How are the main classes of arthropods classified according to the presence of larval stage in their embryonic development?
Last Answer : In crustaceans there are species with direct and others with indirect development. In insects there are species without larval stage (ametabolic insects), others undergoing indirect ... while holometabolic insects undergo complete metamorphosis. Phylum Arthropoda - Image Diversity: metamorphosis
Description : Is the embryonic development in earthworms direct or indirect?
Last Answer : In earthworms there is no larval stage, so the embryonic development is direct.