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Right option is (d) Pericarp

To EXPLAIN: Ovaries develop into FRUITS which further develop a thick WALL covering called the pericarp. The major function of the pericarp is PROTECTION. After fertilization all flower parts wither and fall off.

Right choice is (a) EMBRYO

Best explanation: Zygote develops into an embryo. It happens through a series of CELL DIVISION and cell differentiation. In case of flowering plants, the zygote develops into an embryo and the ovule develops into a SEED.

Correct option is (c) Viviparous

For explanation I WOULD say: Since zygote development takes place inside the female body, they are in a protected environment. Unlike the OVIPAROUS ANIMALS, which are vulnerable. The chances of oviparous animals to SURVIVE is low.

The correct choice is (a) True

Explanation: SINCE development of oviparous ANIMALS takes place OUTSIDE the BODY, they develop a calcareous outer shell that provides protection for the ZYGOTE. The eggs are laid in a safe place. After a period of incubation, the eggs hatch to give young ones.

Correct CHOICE is (b) Oviparous

The best I can explain: ANIMALS are categorized into 2 types of–oviparous and viviparous. Oviparous animals are those animals in which ZYGOTE development takes place outside the BODY. Reptiles and birds are examples of oviparous animals.

Correct choice is (b) Viviparous

The best EXPLANATION: Animals are CATEGORIZED into 2 TYPES of–oviparous and viviparous. Viviparous animals are those animals in which zygote development takes place within the body itself. MAMMALS are a very good EXAMPLE for viviparous reproduction.

Right CHOICE is (d) Humans

Easiest explanation: Syngamy is the PROCESS of fertilization that produces a diploid cell on the fusion of two haploid CELLS. It is also often called internal fertilization since the process takes place on the inside. However, there are few species of organisms where syngamy occurs outside their BODIES, in an external medium. Example, algae, fishes, AMPHIBIANS, etc. This is also called as external fertilization.

Right answer is (b) MEIOSIS

Easy explanation: Organisms having haplontic lifecycles, zygote divides by meiosis to FORM haploid spores that grow into haploid INDIVIDUALS. Formation of zygote FORMS the vital LINK, ensuring continuity of the species.

Right answer is (a) False

The best explanation: External fertilization is not at all SAFE. This is because the gametes have no protection. This makes them vulnerable and more prone to threatens and ATTACKS from predators which decreases their SURVIVAL RATES.

Correct answer is (C) Fertilization

The BEST explanation: Sexual reproduction is divided into 3 events. Pre-fertilization, fertilization and post-fertilization events. Pre fertilization is the events OCCURRING before FUSION of gametes (gametogenesis), fertilization is the fusion of gametes to form zygote and post-fertilization are the events occurring after zygote formation.

Correct choice is (B) Pollen tube

To explain: Non motile pollen GRAINS are carried to the female gamete via a pollen tube which extends from the STIGMA, all the way through the style, REACHING the ovaries. Wind, water, insects, etc. are just ways of mode of transportation for cross pollination.

Correct choice is (d) Internally

Easy explanation: SYNGAMY is the fusion of 2 HAPLOID gametes to form a diploid zygote. This process of fusion happens internally inside the female BODY. Because of this, syngamy is also often known as internal fertilization.

Right option is (c) Lack of adaptability

To elaborate: SINCE there is no FERTILIZATION of gametes taking place, there is no CROSSING over of genes taking place. This hence causes no variations in the generations. This makes it difficult for the offspring to ADAPT to the changing ENVIRONMENTAL conditions.

The correct OPTION is (B) Genotype

Easy explanation: Since there is no fertilization, there is no CROSSING over of genes, hence the genotype is retained throughout GENERATIONS in parthenogenesis. This MEANS no variety in the population.

Correct choice is (c) virgin BIRTH

The best I can explain: It is reproduction without fertilization. This means, the egg or OVUM or the female gamete is not fertilized by the male gamete. The offspring HENCE born is haploid. SINCE there is no fertilization INVOLVED, it is called as virginal reproduction or virgin birth.

Correct option is (c) Fertilization

To elaborate: SYNGAMY is the process of fusion of a haploid MALE(n) and a haploid female(n) GAMETE. On fusion, the zygote or the egg formed is diploid(2n). OFTEN this process is also known as fertilization.

Right choice is (a) Fusion of gametes

Easiest EXPLANATION: Fertilization is the most important event in sexual reproduction. It is the process of fusion of 2 HAPLOID gametes of different sex, FORMING one single diploid zygote. Also known as syngamy.

Correct option is (c) pollen grain

To EXPLAIN: The pollen grains carry the male ORGAN. Mostly the male ORGANS are the motile gamete while the female organ is STATIONARY. It is necessary for the male organs to be small and LIGHT for easy propagation by the environmental agents.

Correct answer is (a) HETEROGAMETIC

The best I can explain: All heterogametic SPECIES can PRODUCE 2 types of gametes, male and FEMALE, their sex chromosomes are unidentical. Homogametic species the sex chromosomes are identical.

Right option is (d) MONOECIOUS

To explain I would SAY: A plant having both reproductive organs in the same plant is known as monoecious PLANTS. It may also be known as homothallic conditions. Dioecious plants are those which have only one reproductive ORGAN, also known as UNISEXUAL plants. Another word for dioecious plants is heterothallic.

Right option is (b) COCKROACH

Explanation: Cockroach is an example of a UNISEXUAL ORGANISM, which means it can produce only one type of gamete, either male or female. Leech, tapeworm and EARTHWORM are bisexual organisms, organisms that can produce both gametes.

Correct answer is (d) STAMEN

Easiest explanation: Stamens are the male organs of a flower. Flowers MAYBE unisexual (EITHER STAMINATE or pistillate). In staminate plants only the male part, that is the stamen, is present and in the pistillate plants only the female part is present (ovaries). In bisexual plants, both are present.

Correct choice is (a) Antherozoid

To ELABORATE: MALE gamete is called antherozoid or sperm. They are called so in HETEROGAMETES. The TWO gametes produced are morphologically distinct TYPES. The female gamete is called egg or ovum.

Correct CHOICE is (a) False

Easy explanation: Gametes are haploid. In GAMETOGENESIS, during the fusion of 2 gametes (male + female), 2 haploids make a diploid. The NUCLEUS of the 2 gametes fuses which MAKES the zygote or egg diploid.

The correct answer is (a) False

The EXPLANATION: Sexual reproduction, unlike asexual reproduction is a slow process. SINCE it is the fusion of 2 opposite sex gametes, it produces VARIATIONS better than the parent. The TIME period varies from specie to specie.

Right CHOICE is (b) Hormones

The best EXPLANATION: Hormones are CHEMICAL messengers that travel through the BLOODSTREAM (in case of ANIMALS). Hormones are responsible for the change in the phases in both plants and animals. Hormonal change can be affected by environmental factors too.

The correct option is (C) Perennial

The BEST I can explain: It is difficult to clearly distinguish between the different phases in perennial plants. Some plants EXHIBIT UNUSUAL flowering PHENOMENA. Some plants flower every year, there are some that flower every 10 years and some plants flower every 50 years. Neelakurinji is a flowering plant that flowers every 12 years.

The correct option is (a) Monocarpic

The best explanation: Monocarpic PLANTS flower only once in its lifetime. They DIE after flowering. Annuals like marigold, wheat, paddy, biennials like RADISH, perennials like Bambusa tulda which flowers EVERY 50-100 years, fruits and DIES.

Correct option is (d) REPRODUCTIVE PHASE

To elaborate: The phase when it is growing is known as the juvenile phase or the vegetative phase (in plants). The phase after that when the reproductive organs in the organism matures is known as the reproductive phase. Senescence is the phase when the PLANT starts DETERIORATING as it grows old and finally dies.

Right option is (C) POLYCARPIC

Easiest explanation: Polycarpic plants are those that flower repeatedly, which means they do not die after flowering once. Examples are perennials like apple, MANGO and PERENNIAL flowers like china rose, it flowers throughout the year.

Right choice is (d) JUVENILE, reproductive, SENESCENCE

For explanation: There are 3 PHASES in a life cycle.

i. Juvenile phase/ vegetative phase: PERIOD from birth to maturation of reproductive systems.

ii. Reproductive phase: period when the reproductive systems have matured and ready to produce offspring.

iii. Senescence: period when the organism starts growing old and starts degrading.

The CORRECT choice is (a) Parthenogenesis

The explanation: Parthenogenesis is a process of REPRODUCTION where the ovum is unfertilized. In case of BEES the eggs are haploid which subsequently makes the male bee haploid. It is a type of asexual reproduction. This type of reproduction takes place in LOWER plants like APHIDS.

Correct CHOICE is (a) Fusion of male and FEMALE gamete

Explanation: The fusion of a haploid male (23 CHROMOSOMES) and a haploid female gamete (23 chromosomes) produces a diploid (46 chromosomes) egg or a zygote. This PROCESS of reproduction is KNOWN as sexual reproduction.

Correct CHOICE is (c) Binary fission

For explanation I would say: Starfish reproduces by binary fission. Just like the single CELLED organisms, starfish breaks along the CENTRAL axis. The 2 separate halves then lead an independent life by forming or regenerating the limbs and missing PARTS.

Right OPTION is (d) Sucker

For explanation: In suckers the lateral branches arise from basal and underground PORTIONS of the MAIN STEM. They GROW horizontally underground and the leafy shots arise from the soil. For example, bananas.

The correct answer is (a) TULIP

The best I can explain: Tulip is an EXAMPLE of a bulb. It is a vegetative propagation by UNDERGROUND stems. They have more than one TERMINAL buds. Another very common example is the ONION. Oxalis is and example of a runner and the other 2 are examples of vegetative propagation by leaves.

The correct option is (c) Conidia

To explain I would say: Conidia are non-motile FUNGAL spores that are produced SINGLY or in chains by constriction of tips of conidiophores and are dispersed by wind. Zoospores are motile fungal spores. Gemmules are REPRODUCTIVE structures of sponges and nodes are just a site on the stem from where the new plant arises in rhizomes (VEGETATIVE propagation).

The correct ANSWER is (a) True

Easy explanation: Binary FISSION is a type of asexual reproduction where the parent cell splits into 2 daughter cells. One is irregular, like the one that takes PLACE in amoeba. It takes place along any plane. The other is transverse, like in paramecium. It divides the organism width WISE, that is along the transverse axis.

The correct ANSWER is (a) Lolium multiflorum

Easiest EXPLANATION: Lolium multiflorum also known as LAWN grass is a TYPE of runner. Narcissus is a PLANT that reproduces by bulb formation, like onions and the other 2 are plants that reproduce by adventitious buds.

Correct answer is (a) Thick runner

Easy explanation: Offset is a thick runner type BRANCH that helps in vegetative PROPAGATION by sub aerial stems. It can grow even if there is an injury and it will grow INDEPENDENTLY. Examples are PISTIA, Eichhornia.

Right answer is (d) Adiantum caudatum

To explain I WOULD say: Adiantum caudatum is commonly KNOWN as walking fern. This is because their LEAF tips form new plants when they come in contact with the soil. Others are an EXAMPLE of plants that reproduce by leaves. It forms buds on the notches and falls off when old enough to grow on its own. In BEGONIA, the injured leaf grows into a new plant.