Q1(NEET 2021): A specific recognition sequence identified by endonucleases to make cuts at specific positions within the DNA is:
(a) degenerate primer sequence
(b) Okazaki sequences
(c) palindromic nucleotide sequence
(d) poly(A) tailsequence
Q1: The linking of antibiotic resistance gene with the plasmid vector became possible with
(a) DNA polymerase
(b) exonucleases
(c) DNA ligase
(d) endonucleases
Q1: The organisms which cause diseases in plants and animals are called:
(a) Pathogens
(b) Vectors
(c) Insects
(d) Worms
Q2: The sporozoites that cause infection, when a female Anopheles mosquito bites a person, are formed in:
(a) Liver of the person
(b) RBCs of mosquito
(c) Salivary glands of the mosquito
(d) Intestine of mosquito
Q1: A common biocontrol agent for the control of plant diseases is
(a) baculovirus
(b) Bacillus thuringiensis
(c) Glomus
(d) Trichoderma
Q2: Methanogens do not produce
(a) oxygen
(b) methane
(c) hydrogen sulfide
(d) carbon dioxide
Q1. A majority of organisms that are restricted to a narrow range of temperature are called as
(a) stenothermal
(b) endothermal
(c) ectothermal
(d) eurythermal
Q1. Which one is the most important human activity leading to extinction of wildlife?
(a) Alteration and destruction of the natural habitats.
(b) Hunting for commercially valuable wildlife products.
(c) Pollution of air and water.
(d) Introduction of alien species.
Biology - Human Health and Diseases
Following are the diseases that can affect the circulatory system:
⑴ Hypertension:
It is the most common disease affecting the heart and blood vessels. A blood pressure of 120/80 mmHg is considered normal. But the increase in blood pressure beyond 140 mmHg (systolic) and 90 mmHg (diastolic) is called high blood pressure (hypertension). A diet full of oily food is known to increase cholesterol levels, causing thickening of the arteries which results in high blood pressure. Tobacco smoking increases the heart rate, contracts blood vessels and raises blood pressure. High blood pressure can harm the heart, brain, kidneys and eyes.
Q1. What are Transgenic crops?
Answer: Genetically modified crops that contain or express one or more useful foreign genes are called transgenic crops.
Q2. What are transgenic animals? Give an example.
Answer: Animals manipulated with the foreign gene and have the ability to express it are transgenic animals. e.g. Rosie, a transgenic cow produced milk containing human alpha-lactalbumin.
Q3. What is BT toxin?
Answer: Bt toxin is an intracellular crystalline protein. It exists as an inactive protoxin that once ingested by an insect, gets activated, binds to the surface of midgut epithelial cells. This causes cell swelling and lysis, leading to the death of an insect.
CBSE (Central Board of Secondary Education) has released the Sample Paper for Class 10 12 Term 2 Exams 2022. CBSE released the sample papers on their official website for both the Classes 10th and 12th and these papers are in a subjective format.
Students can check the sample paper at https://cbseacademic.nic.in/
These papers are in a subjective format.
Q1: The outermost and innermost wall layers of microsporangium in an anther are respectively.
(a) Endothecium and tapetum
(b) Epidermis and endodermis
(c) Epidermis and middle layer
(d) Epidermis and tapetum
Q2: Which of the following fruit is a case of parthenogenesis?
(a) Fruit without seeds after pollination
(b) Fruit with seeds after pollination
(c) Fruit with viable seeds without fertilization
(d) Fruit with viable seeds after fertilization.
Q1: Which of the following statements is wrong for viroids?
(a) They cause infections.
(b) Their RNA is of high molecular weight.
(c) They lack a protein coat.
(d) They are smaller than viruses.
Q1: Define life span.
Answer: Life span is the period from birth to the natural death of an organism.
Q2: What is the life span of the following organisms?
(a) Mayfly
(b) Human Being
(c) Parrot
(d) Rice Plant
(e) Sequoia Trees
(f) Butterfly
Answer:
(a) Mayfly - 1 day
(b) Human Being - 100 years
(c) Parrot - 140 years
(d) Rice Plant - 3 to 4 months
(e) Sequoia Trees - 3000 to 4000 years
(f) Butterfly - 1 to 2 weeks
Q1(MCQ): Clones are
(a) Morphologically similar
(b) Genetically similar
(c) Both (a) and (b)
(d) None of these
Answer: (c) Both (a) and (b)
Clones are morphologically and genetically similar individuals.
Q2: Define Parthenogenesis.
Answer: Parthenogenesis is the development of an egg into an embryo without fertilisation. e.g. in rotifers, honeybees, turkey and some lizards.
Q1: Define immunity.
Answer: Immunity means resistance to infections and antigens. Immunity is the capacity of an organism to resist or defend itself from the development of a disease.
Q2: What is an antigen? Give some examples.
Answer: Any substance or molecule that induces the immune system to produce antibodies against it is called an antigen. Examples include pathogens, virus, pollens, chemicals etc.
Q3: Name two main types of immunities.
Answer:
1. Innate immunity
2. Acquired immunity
2. Which Vitamin is known as the anti-infetive vitamin
3. Which Vitamin is used for ELISA test (AIDS)?
4. Which Vitamin contains Cobalt?
1. Swedish botanist Carolus Linnaeus established binomial nomenclature.
2. Caper Bauhin expressed proposed binomial nomenclature for the first time
3. In binomial nomenclature, the first word is a generic name having first letter capital and second word is a specific epithet having first letter. e.g. Homo sapiens, Mangifera indica
4. After end of biological name, the name of author is written in abbreviated form who gave the name to that organism.
5. Both the words of a biological name when handwritten are separately underlined and when printed are typed in italics to indicate their Latin origin and also give respect to the name.
CBSE Class 11 Biology - The Living World
Q1: Do five kingdom classification include viruses, viroids and lichens?
Answer: Five kingdom system of classification do not includes Virus, Viroids and Lichens.
Q2: What is a virus? What is its structure?
Answer: Viruses are non-cellular organisms having inert crystalline structure outside the living. A virus is a small particle consisting of a nucleic acid core surrounded by a protein coat; in order to reproduce, a virus must infect a living cell.
