DAILY QUIZ- NOV 29

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1. Consider the following statements about

1) Black corals can be found growing both in shallow waters and down to depths of over 8,000 meters.

2) Corals can survive only under saline conditions with an average salinity between 27% to 40%.

3) Black corals are omnivores.

Which of the above statements is/are correct?

a) 1 and 2 only

b) 2 and 3 only

c) 1 and 3 only

d) 1, 2 and 3

Answer: A

Explanation:

Black Corals:

· Colonial animals: Black corals or antipatharians are colonial animals which are related to sea anemones and stony corals.

· They are named for the color of their stiff, black or brownish skeleton.

· More than 150 species of black corals have been described. At least 14 species of black corals are currently known from Hawai’i.

· Distribution: Black corals are found in all oceans, but are most common in deep water habitats of tropical and subtropical seas.

· Black corals are carnivores.

Characteristics

· Black corals can be found growing both in shallow waters and down to depths of over 26,000 feet (8,000 meters), and some individual corals can live for over 4,000 years.

· Many of these corals are branched and look like feathers, fans or bushes, while others are straight like a whip.

· Black corals are filter feeders and eat tiny zooplankton that are abundant in deep waters.

· While colourful shallow-water corals rely on the sun and photosynthesis for energy.

· Similarly to shallow-water corals that build colourful reefs full of fish, black corals act as important habitats where fish and invertebrates feed and hide from predators in what is otherwise a mostly barren sea floor.

What are Coral Reefs?

· A coral reef is an underwater ecosystem characterised by reef-building corals.

· Formation :

Coral reefs are formed over a process of thousands of years. Each coral reef is made up of colonies of tiny animals called polyps.
Each polyp produces calcium carbonate, which makes up their skeleton and protects corals internal bodies; similar to how our skeleton protects our organs.

· The coral polyps live in an endosymbiosis relationship with algae. Algae provides up to 90 per cent of the coral's energy.

· Temperature:

· The temperature of the water should not be below 20°C.

· The most favourable temperature for the growth of the coral reefs is between 23°C to 25°C.

· The temperature should not exceed 35°C.

· Salinity: Corals can survive only under saline conditions with an average salinity between 27% to 40%

· Shallow Water: Coral reefs grow better in shallow water having a depth less than 50 m. The depth of the water should not exceed 200m.

· Coral reefs are divided into four classes:

· Fringing reefs

· Barrier reefs

· Atolls

· Patch reefs.

· Corals are of two types:

Hard corals: Hard corals extract calcium carbonate from seawater to build hard, white coral exoskeletons. Hard corals are in a way the engineers of reef ecosystems and measuring the extent of hard coral is a widely-accepted metric for measuring the condition of coral reefs.
Soft corals: Soft corals attach themselves to such skeletons and older skeletons built by their ancestors. Soft corals also add their own skeletons to the hard structure over the years. These growing multiplying structures gradually form coral reefs.

· Bleached corals can survive depending on the levels of bleaching and the recovery of sea temperatures to normal levels.

2. Consider the following statements about Blue Bugging:

1) It is a form of hacking that lets attackers access a device through its discoverable WiFi connection.

2) It started out as a threat to laptops with WiFi capability.

Which of the above statements is/are correct?

a) 1 only

b) 2 only

c) Both 1 and 2

d) Neither 1 nor 2

Answer: D

Explanation:

Bluebugging:

· Background: Independent security researcher Martin Herfurt blogged about the threat of bluebugging as early as 2004.

o the bug exploited a loophole in Bluetooth protocol, enabling it to download phone books and call lists from the attacked user’s phone.

· It is a form of hacking that lets attackers access a device through its discoverable Bluetooth connection.

· Once a device or phone is bluebugged, a hacker can listen to the calls, read and send messages and steal and modify contacts.

· It started out as a threat to laptops with Bluetooth capability.

o Later hackers used the technique to target mobile phones and other devices.

· Threats: Bluebugging attacks work by exploiting Bluetooth-enabled devices.

o The device’s Bluetooth must be in discoverable mode, which is the default setting on most devices.

o The hacker then tries to pair with the device via Bluetooth. Once a connection is established, hackers can use brute force attacks to bypass authentication.

o They can install the malware in the compromised device to gain unauthorised access to it. Bluebugging can happen whenever a Bluetooth-enabled device is within a 10-meter radius of the hacker

· Ways to prevent: Turning off Bluetooth and disconnecting paired Bluetooth devices when not in use, updating the device’s system software to the latest version, limiting use of public Wi-Fi, and using VPN as an additional security measure are some of the ways to prevent bluebugging,

o Users must also watch out for suspicious activities on their devices.

3. Har Ghar Gangajal scheme is associated with------------------

a) Help to distribute the water from the Ganga through tap

b) Help to harvest the excess water of the Ganga

c) Help to secure the Ganga from pollution

d) Help to store the water from the Ganga through reservoir

Answer: C

Explanation:

Har Ghar Gangajal scheme:

· It is a unique and ambitious initiative to provide Ganga water on tap in the parched areas of the state.

· The scheme will help to harvest the excess water of the Ganga during the monsoon season.

· The water will be stored in reservoirs in Rajgir and Gaya before being channeled to three treatment-and-purification plants, from where it will be supplied to the public.

· Har Ghar Gangajal is part of the Bihar government’s Jal, Jeevan, Hariyali scheme.