Utricularia are carnivorous plants which capture small prey with remarkable suction traps. These are rootless plants formed of very thin, forked leaves. Only the flower remain out of the water while the whole trap is underwater. When an aquatic animal touches its sensitive hairs, the traps suck it in, in just a few seconds, along with water, which is then drained through its walls.

Plants which synthesise their food themselves are called autotrophs. That is, it doesn't depend on other organisms for food, using sunlight and water the plants makes their own food. They are considered as the producers in a food chain. Saprotrophs are the plants which feeds from the dead and decayed organic matters knows as detritius. Major saprotroph group includes fungi, bacteria and water molds.

Bt toxin gene has been closed from the bacteria and expressed in plants to provide resistance to insects without the need for insecticides. Examples are Bt cotton, Bt corn, rice, tomato, potato and soybean, etc.

Vivipary is a condition where seeds germinate on the plant. Most of the food crops are annuals and seeds are consumed as food. Therefore, if seeds germinate on the plant they cannot be utilized as food nor can they be stored for the next season. So, the correct answer is 'The seeds cannot be stored under normal conditions for next season'

A bisexual flower (or “perfect”) has both stamens and carpels, and a unisexual flower (or “imperfect”) lacks stamens is called staminate.

(A) Insectivorous plants are the plants that feed on insects.

• An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water or from debris accumulating around it.
• Most epiphytic orchids are found growing in tropical areas below the canopy of trees. Epiphytic orchids have adapted to obtain water and nutrients that grow with their roots which are located aerially.
  
• They have thick, spongy roots that absorb and store water and nutrients from the sporadic rainfall to be used over time.
  

• Pitcher plants are several different carnivorous plants which have modified leaves (act as a pitcher) which are known as pitfall traps—a prey-trapping mechanism featuring a deep cavity filled with digestive liquid. 
• These plants trap harmful insects and kill them with the help of digestive fluid.

Symbiosis is any type of close and long-term biological interaction or relationship between two different biological organisms, be it mutualistic or commensalistic. It is usually a form of beneficial relationship in which both organisms are benefited.

• A parasite is an organism that lives on or in a host organism and gets its food or nutrition from its host (plants and animals). There are three main classes of parasites that can cause disease in humans: protozoa, helminths, and ectoparasites.
• Parasites come in many shapes and sizes and include viruses and bacteria, various worms, plants, fungi, insects, and even birds and mammals.
  

• Drosera, commonly known as the sundews, is one of the largest genera of carnivorous plants with at least 194 species.
•  They lure, capture, and digest insects using stalked mucilaginous glands covering their leaf surfaces. 
• Sundews are perennial (or rarely annual) herbaceous plants. Sundews have been shown to be able to achieve a lifespan of 50 years.

• A lichen is a symbiotic association between one or two fungus species and an alga or cyanobacterium (blue-green algae). Lichens were once classified as single organisms, until the advent of microscopy, when the association of fungi with algae or cyanobacteria became evident.
• Lichens may have powdery masses on their surface. These are the tiny bits of the lichen body which will be shed to form new lichens.
  

Algal bloom is a rapid increase or accumulation in the population of algae in an acquatic system. The nutrients like potassium and nitrogen are key nutrients for the growth of algae. The presence of these materials and availability of sunlight are key factors for the growth of algae.

Dodder plant, which belongs to the genus Cuscuta is a yellow, orange, or red (rarely green) parasitic plants. After dodder attaches itself to a plant, it wraps itself around it. If the host contains food beneficial to dodder, the dodder produces haustoria that insert themselves into the vascular system of the host. The original root of the dodder in the soil then dies.

For the canopy to spread over a large area the root system also has to be robust so as to provide enough nutrients and anchorage. Wide spreading and deep roots are tap root systems that are characteristic to dicotyledonous plants.

A parasite depends on its host to stay alive. Killing the host before the reproduction destroys parasite also as it needs host to produce its progeny generation after generation. This makes option D correct. In order to keep the host alive to produce many generations of parasite offspring, it is necessary for a parasite to become less virulent or gentle over many generations. This makes option A incorrect. Fast reproduction produces increase the number of parasite offspring but poses extra burden on host and makes the host survival harder. This makes option B incorrect. Similarly, sticking too long to a host decreases its survival chances and hence, parasite keeps switching the host over time. Option C is incorrect. Thus, the correct answer is option D.

Cuscuta (Dodder) plant is an obligate or total stem parasite. It lacks chlorophyll and has no connection with the soil after the seeding stage. Therefore it is totally dependent on the host for organic food materials and supply of water and minerals salts. The parasitic plant pierces the stem and sucks the nutrients from the host plant.

The Venus flower basket, or Euplectella aspergillum is a hexactinellid sponge in the phylum Porifera inhabiting the deep ocean. In traditional Asian cultures, this particular sponge (in a dead, dry state) was given as a wedding gift because the sponge symbiotically houses two small shrimp, a male and a female, who live out their lives inside the sponge. They breed, and when their offspring are tiny, the offspring escape to find a Venus flower basket of their own. The shrimp inside the basket clean it and, in return, the basket provides food for the shrimp by trapping it in its tissues and then releasing wastes into the body of the sponge for the shrimp. It is also speculated that the bioluminescent light of bacteria harnessed by the sponge may attract other small organisms which the shrimp eat. 

Rafflesia is a genus of parasitic flowering plants. It contains approximately 28 species, all found in southeastern Asia, in Indonesia, Malaysia, Thailand and the Philippines. It is not a saprophytic angiosperm. Cuscuta, Loranthus and santalum are stem parasites. Nepenthes, Drosera and Dionaea are the insectivorous plants. Mangrove plants are seen in saline marshy lands. 

• Trypsin is working as a digestive enzyme to break down proteins in the small intestine.
• Some plants eat insects. Such plants are called insectivorous plants. They trap and digest insects. The insect is then digested by the enzyme pepsin secreted by the cells of the plants. Example -The protease secreted in the pitcher fluid is pepsin-like.
• Pectinase is the enzyme that breaks down pectin and polysaccharides found in plant cell walls.
• Cellulase is the enzyme that converts cellulose into glucose or a disaccharide.

So option B is correct.

Aldrovanda is an insectivorous plant as it feeds on insects. Aldrovanda vesiculosa, commonly known as the waterwheel plant, captures small aquatic invertebrates using traps similar to those of the Venus flytrap. The traps are arranged in whorls around a central, free-floating stem.

The green plant is photoautotrophs that synthesise food material from simple inorganic compounds like water and carbon dioxide in the presence of sunlight. 
Nutrition in Amoeba and Paramecium is holozoic. Thus, solid food particles are ingested which are then acted upon by enzymes and digested. Cuscuta, lice, and tapeworm are parasites with the heterotrophic nutritional mode. Yeast, mushroom and bread mould have a saprophytic mode of nutrition which is chemoheterotrophic in nature. They break down complex organic substances by secreting digestive enzymes outside their body and absorb simple molecules as nutrients. So, the correct answer is option B.  

A species has a specific number of chromosomes and onion has only 16  chromosomes which are the least number among given options so the answer is option A, Onion.

Rafflesia is the largest flower that is found on the earth. It is an angiosperm and is an obligate root parasite. An obligate root parasite is the one that cannot complete its life cycle without the presence of a host and derive the nutrition from the host entirely.

Epiphytes are the plants which grow on the other plants for the support as they are weak themselves. They don't harm the plant on which they grow. They obtain their nutrients and moisture from the air. For example : mosses.

Arceuthobium is the genus of parasitic plants. The host of this plants are members of Pinaceae and Cupressaceae. The stem is reduced and the leaves are minute structures. The flowers are sessile. Most of the parasitic plant is covered beneath the bark of the host plant. 

The aerial roots of plants absorb moisture from the air. These roots are seen in epiphytes which grow on the surface of other plants.  Epiphytic plants take nutrition from air, rain and surrounding organic debris, as they are not in contact with soil. Orchids are epiphytes which have aerial roots with a modified spongy layer of the epidermis called velamen which can absorb moisture from humid air. The cells of velamen absorb water during rains and store for future.

Aldrovanda is a free-floating and rootless aquatic plant. It functions as a snap-trap carnivore under water. A common name for it is the waterwheel plant, because a single whorl of leaves, cut from a stem, is wheel-like. Snap traps are only found in one other carnivorous plant genus, Dionaea, which comprises the commonly known Venus flytrap. 

Like all green plants, pitcher plants use their leaves to harness energy from the sun and make their own food; they use carbon dioxide (CO$ _{2}$) to make energy-rich carbohydrates. So, they are producers. 

Saprophytes are the class of organism that have saprophytic mode of nutrition. They feed on dead living organism. They are assumed to have evolved from green plants but have lost their chlorophyll during the course of evolution.

Plant materials include a wide and varied group of plant parts from many species. General categories of plant materials include grasses, rushes, barks, woods, gourds, stems, roots, seeds, and leaves. These materials can be used to construct baskets, netting, cordage, and even fabrics. Common production methods include felting, knitting, knotting, coiling, plaiting, and weaving. 

Weak stemmed plants climb over the support are called twinners. They climb by the stem itself.