Roman Saini is teaching live on Unacademy Plus
Q61. Which of the following statements is/ are correct? 1. Stomata in plants are involved in respiration. 2. Stomata in plants are involved in transpiration. 3. Stomata in plants help in transport of water and minerals. Choose the correct statement/ statements. a. b. 2 only 1 only c. 1 and 2 only d. 1, 2 and 3
Answer:d Explanation: Stomata are minute pores in leaves of plant which help in exchange of gasses as well as transpiration. Transpiration helps in transport of water and minerals from roots to all the parts of the plant. It creates a suction pull which helps in pulling water to leaves and other parts of the trees.
Q62. What do you understand by vegetative propagation? a. a. t is the scientific method of growing vegetables. It is the sci is the process by which vegetables grow in size and weight. It is a form of reproduction in plants in which the vegetative parts of the plant grow into a new plant. It is a form of traditional agricultural farming b. b. Iti C. d. is a form of traditional agricultural farming.
Answer: c Explanation: It is a form of reproduction in plants in which the vegetative parts of the plant (roots, leaves, stem), when planted into the soil grow into a new plant. Vegetative parts which grow into a new plant: Roots- Sweet potato and dahlia Stem- Potato (eye), ginger, turmeric, Champa, rose Leaves- Bryophyllum (sprout leaf plant)
Q63. Which of the following is a plant in which any of the parts can grow into a new plant? a. Rose b. Cactus c. Ginger d. Sugarcane
Answer: b Explanation: Self-explanatory.
064. Consider the following statements: 1.Plants can reproduce by vegetative propagation only. 2. Plants produced by vegetative propagation take less time to grow than plants produced from seeds. Choose the correct statement/ statements. a. b. C. d. 1 only 2 only Both of the above. None of the above.
Answer: b Explanation: Plants can reproduce by vegetative propagation (asexual produced by vegetative propagation take less time to grow than reproduction) as well as from seeds reproduction) as well as from seeds (sexual reproduction). Plants plants produced from seeds.
Q65. Which of the following organisms and their mode of reproduction are correctly matched? 1.Yeast- Budding 2 Algae- Fragmentation 3. Fungi- spore formation Choose the correct code. a. b. 1and 3 only C. d. 1, 2 and 3. 1 only 2 and 3 only
Answer: d Explanation: Fragmentation occurs when a parent organism breaks into fragments, or pieces, and each fragment develops into a new organism Budding occurs when a parent cell forms a bubble-like bud. The bud stays attached to the parent cell while it grows and develops. When the bud is fully developed, it breaks away from the parent cell and forms a new organism. Spores are asexual reproductive bodies. Each spore is covered by a hard protective coat to withstand unfavourable conditions such as high temperature and low humidity. So they can survive for a long time. Under favourable conditions, a spore germinates and develops into a new individual. Plants such as moss and ferns also reproduce by means of spores.
Q66. Consider the following statements: 1. Stamen is the female reproductive part of a plant. 2. Pistil is the male reproductive part of a plant. Choose the correct statements a. b. 2 only c. Both 1 and 2 d. None of the above 1 only
Answer:d Explanation: Stamen is the male reproductive part of a plant while as pistil is the female reproductive part of a plant. A stamen consists of anther (contains pollen grains/ male gametes) and filament. A pistil consists of stigma, style and ovary (contains one or more ovules, in which female gamete/ egg develops).
Answer: a Explanation: After fertilisation, the ovary grows into a fruit and other parts of the flower fall off. The fruit is the ripened ovary. The seeds develop from the ovules. The seed contains an embryo enclosed in a protective seed coat.
Q69. Which of the following is not a means of seed dispersal? a. Water b. Wind C. nsects d. Pollination
Answer: a Explanation: Self-explanatory
Q71. Odometer in vehicles, is a device used to measure a. b. C. Speed d. RPM Time Distance
Answer: b Explanation: Tachometer measures the revolutions per minute (RPM) of the wheel, while as odometer measures the total distance travelled by a vehicle. Speedometer measures the speed of the vehicle
Q73. . Time-keeping services in India are provided by a. National Physical Laboratory, New Delhi b. Ntional Physical Laboratory, Chennai C. National time services, Delhi d. National time services, Chennai
Q74. Wires used to make electric fuses a. Melt quickly b. Melt slowly c. Don't melt at all d. Melt with difficulty but quickly
Q74. Electric bulb was discovered by a. William Harvey b. Thomas Elva Edison c. Michael Filament d. hnny Tungsten
Answer: b Explanation: Self-explanatory
075. Consider the following statements regarding image formation by a plain mirror: 1. Image formed by a plane miror i erticlly inverted. Image formed by a plane mirror is vertically inverted. Image formed by a plane mirror is equal in size to the object. 2. 3. Image formed by a plane mirror is at the same distance behind Choose the correct statements. a. 1 and 2 only b. 2 and 3 only the mirror as the object is in front of it. 1 and 3 only 1, 2 and 3 C. d.
Answer: b Explanation: Image formed by a plane mirror is virtual, of the same size as the object and it is erect but laterally inverted i.e. left side of the object seems to be the right size of the image and vice versa. This is the reason why "AMBULANCE" is written as "ECNALUBMA". When the driver of a vehicle ahead of an ambulance looks in her/his rear view mirror, she/he can read AMBULANCE written on it and give way to it.