Meiosis occurs in:
Megaspore mother cell is diploid so meiosis occurs in it.
Mitotic anaphase differs from metaphase in possessing:
So, the correct answer is option D.
The product of hybridization is known as
Mitosis can be studied in:
► Cell division is the basic requirement for the growth and development of the body, if the cells top dividing the body will eventually die.
There are two types of cell divisions:
► In plants, mitosis occurs in the meristems which have the ability to divide continuously.
Meristems in plants are of two types:
Plants don’t repair or replace their damaged parts like leaves, branches but for new ones due to the continuous production of new cells in the meristems.
Mitosis in Onion Root Tips:
Which of the following is a social foresting species with multiple utility?
Leucaena leucocephala (Subabul) is a social foresting species with multiple utility like green manure, biomass production, food for humans, pulpwood for paper industry etc
Which among the following is the man made cereal?
Triticale is the only cereal obtained from hybridization, where the required character of 2 different or similar species and merged to form new individual.
During extreme aridity, Desert Rat ______ .
Green plants constitute:
It is because they are the primary source of energy and every food chain starts with a producer because they produce their own food and pass energy for the other tropical level.
Energy enters into the ecosystem through
Sun is the ultimate source of energy and plants (producers) are the only ones who can convert sunlight into chemical energy. Hence producers bring energy into the ecosystem.
IPM (Intergrated Pest Management) involves:
A plant with both male and female flowers borne over it is:
Monoecious” is translated as “single house,” meaning that male and female flowers are found on a single individual. This contrasts with the translation of dioecious, which is “double house.” This means that male flowers are on one plant and female flowers are on another plant.
During DNA replication, the strands separate by:
In vitro synthesis of RNA and DNA was carried out first by:
Which one codes for an amino acid?
The number of prothallial cells in male gametophyte of Pinus is/are
An allele is dominant if it is expressed in
An alternative form of a character in a pair, controlled by a single gene is called Allele. It is dominant either in a homozygous or heterozygous state.
Mendel formulated the law of purity of gametes on the basis of:
The reason is simple. it was due to the monohybrid cross that Mendel could find that characters that we are not expressed in the F1 generation where expressed in the F2 generation .this could mean gametes independently contained alleles.
F₂ generation of a cross between two white flowered strains of Sweet Pea yields 9 purple flowered plants : 7 white flowered plants. This is an example of
A white flower Sweet Potato(CCpp) is crossed with another white flowered Sweet Potato(ccPP). In the F1 generation, Purple flowered Sweet potato plants are formed. When these plants are subjected to self pollination, in the F2 generation, 9 plants with purple flowers and 7 plants with white flowers are formed. It is complementary genes.
Photosystem-II takes place in
PS II occurs mostly on the granal lamellae of the chloroplast. PS II uses light energy for photolysis of H2O molecules, or oxidizing H2O molecules producing electrons, protons (H+) and O2.
Plants detoxify heavy metals by means of
Plants respond to heavy metal toxicity in a variety of different ways. Such responses include immobilization, exclusion, chelation and compartmentalization of the metal ions, and the expression of more general stress response mechanisms such as ethylene and stress proteins. Phytochelatins are oligomers of glutathione, produced by the enzyme phytochelatin synthase. They are found in plants, fungi, nematodes and all groups of algae including cyanobacteria. Phytochelatins act as chelators, and are important for heavy metal detoxification. They are abbreviated PC2 through PC11.
In presence of high concentration of oxygen,RuBP carboxylase converts RuBP to
C2 cycle or photo respiration will begin and PGA &Phosphoglycolate is formed so,option D..
Light energy is changed to chemical energy in the process of
Photosynthesis in plants converts solar energy into chemical energy using electrons and protons from water.
According to their modes of nutrition, the fungi are classified into
Fungi are classified as per their modes of nutrition as
3. Symbiotic (Mycorrhiza)
These fungi feed on dead organic matter and decaying matter.
Parasitic fungi live or colonise animals, plants and other fungi living on their expenses, inflict diseases or even death.
The mycelium feeds on organic compounds in the soil substrate through decomposition or through particular associations with plants.
The first step in photosynthesis is the
When light is incident on chloroplast, firstly exciting of an electron and then next reactions will occur.
Which of the following depicts the characteristic of both plants and animals?
In the old 5 kingdom system, the group Protista was created because there were some organisms (like Volvox and Euglena) that the scientists could not decide to which of the other groups (Monera, Fungi, Plantae and Animalia) they should belong. They have characteristics of both plants (chloroplasts with chlorophyll, so they can photosynthesize) and of animals (they have flagellae, and for colonies that are capable of coordinated movement).
A paramecium is animal-like because it moves and searches for its own food. The have characteristics of both plant and animal. Sometimes they make food and sometimes they don't. An amoeba is animal-like because of its ability to move.
Agent orange is
Agent Orange is an herbicide and defoliantchemical, one of the "tactical use" Rainbow Herbicides. It is widely known for its use by the U.S. military as part of its herbicidal warfare program, Operation Ranch Hand,during the Vietnam War from 1961 to 1971.It is a mixture of equal parts of two herbicides, 2,4,5-T and 2,4-D. In addition to its damaging environmental effects, traces of dioxin (mainly TCDD, the most toxic of its type) found in the mixture have caused major health problems for many individuals who were exposed.
Bending of stem towards light is
Heliotropism is a growth movement or bending of stem in the direction of the light. It is also called as solar tracking. Photoperiodism is the phenomenon in which various physiological reactions like flowering response to the relative length of dark or light periods. Photonasty is nastic movement of plant towards sunlight. Hydrotropism is a growth movement of plant part in response to water.
If a tree flowers thrice in a year in October, January and July in northern India, the plant is
Plants are able to detect and respond to light, gravity, changes in temperature and chemicals. Plants respond to the changing seasons to initiate their development and flowering. The photoperiodic stimulus is found to be responsible for flowering, light quality, vernalization, autonomous and GA pathways are also responsible for regulating the flowering time in plants. While vernalization and photoperiodic pathways are environmental dependents, the autonomous pathway promotes flowering in all conditions. Hence for a tree that flowers thrice a year, the plant has to be both photo and thermo-insensitive.
Nitrogen fixation occurs in
Nitrogen fixation occurs in some bacteria as rhizobium,cyno bacteria as nostok , anabaena , in node of root of legumes.
In which one of the following pathogens do the cells of promycelium after the germination of teleutospore produce infection hyphae instead of basidiospores?
Which one contains only living cells ?
Parenchyma have primary cell wall and retains the ability for future cell division. They form 'filler' tissues in soft part of plants and are usually present in medullary rays and hence are called living cells.
It is an air pollutant and it affects metabolic activity of cell and disrupts the transport system of the cell and hence affect the whole membrane system.
A person has impaired nervous system and signs of madness due to continued intake of metal contaminated water. The metal is
Lead always impaire our nervous system when anyway it enters in our body.
Which part of the reproductive structure produces both enzymes and hormones?
Tapetum synthesizes callase enzyme which dissolves callose. It produces many hormones ,amino acids and nutrious substances that are needed for pollen grains.
Study of formation, growth and development of new individual from an egg is
Embryology is defined as the branch of biology and medicine that studies embryos and how they develop. The study of how human embryos develop from fertilization to birth is an example of embryology.
Plants often reproduce vegetatively by forming new plants from portions of their
Asexual plant propagation methods produce new plants from vegetative parts of the original plant, such as the leaves, stems and roots. These methods are generally referred to as vegetative propagation.
Energy currency (reservoir) of the cells is
Adenosine triphosphate (ATP) is a complex organic chemical that provides energy to drive many processes in living cells, e.g. muscle contraction, nerve impulse propagation, and chemical synthesis. Found in all forms of life, ATP is often referred to as the "molecular unit of currency" of intracellular energy transfer
Which is wrong about cytochrome P-450 ?
So the correct option is 'it is a coloured cell'.
Velamen is found in
Velamen is a spongy tissue found in aerial or hanging roots of epiphytes (eg : Orchids-Vanda ) It absorbs atmospheric moisture by imbibition.
Modification of stem into leaf like cladodes is found in certain
Cladodes are the modification of stem in leaves which contains chlorophyll for the process photosynthesis in xerophytes plants.
Feathery stigma are present in-
Wheat has animophilly mode of Pollination, and feathery stigma is a characteristic of animophillus flower
Stomata of a plant open due to
This is due to sodium pottasium pump hence when sodium go out of the pottasium ions took the inside place and vice versa.
Which of the following is used to determine the rate of transpiration in plants ?
A potometer is a device used for measuring the rate of water uptake of a leafy plant shoot. The main reason for water uptake by a cut shoot is transpiration (evaporation in plants) and is affected by the transpiration stream.
Of the processes which occur in leaves, the one which may lower their temperature (cooling effect)is
Transpiration lowers the temperature as during transpiration liquid water is absorbed by the plant. In the cells surrounding the substomata chamber, water evaporates from the cell wall into the chamber. When the stomata are open water vapour diffuses out into the chamber Transpiration cooling energy is needed to evaporate liquid into vapour. Energy is absorbed into liquid water and this reduces the temperature of the surrounding plant tissue and nearby atmosphere