Learn 80 questions from K-TET III - November 2019 - Part III (Natural Science)

K-TET III - November 2019 - Part III (Natural Science) Questions

Syphilis, gonorrhea, chlamydia, and trichomoniasis are all sexually transmitted infections (STIs) that are curable with antibiotics:
Symptoms of STIs include:
Abnormal vaginal discharge
Urethral discharge
Genital ulcers and lumps
Lower abdominal pain
Painful or frequent urination
Vaginal bleeding between periods
Rectal bleeding, discharge, or pain

Hemoglobin is a protein made up of four polypeptide chains, or subunits, called globin chains: α-chains, β-chains, γ-chains, and δ-chains.
There are three types of normal hemoglobin, each made up of a different combination of the four globin chains:
Hb A: The most common type of hemoglobin in adults, made up of two α-globin chains and two β-globin chains
Hb A2: Made up of two α-globin chains and two δ-globin chains
Hb F: Also known as fetal hemoglobin, made up of two α-globin chains and two γ-globin chains

Silent Spring is an environmental science book by Rachel Carson. Published on September 27, 1962, the book documented the environmental harm caused by the indiscriminate use of DDT, a pesticide used by soldiers during WW2.

Cyathium and hypanthodium inflorescence resemble each other in possessing unisexual flowers:
Cyathium inflorescence: A cup-shaped structure formed by a condensed floral axis, with an involucre that contains a nectary gland.
Hypanthodium inflorescence: A pear-shaped receptacle formed by a fleshy and closed floral axis

Double-stranded RNA (dsRNA) is processed into short interfering RNA (siRNA) by RNase II enzymes. The siRNA is then loaded into the RNA-induced silencing complex (RISC). The siRNA unwinds and hybridizes with the mRNA target. The Argonaute enzyme then degrades the mRNA.

Proinsulin-A peptide chain and B peptide chain

The Widal test is a blood test that measures the level of antibodies in the blood that fight the bacteria that causes typhoid fever. It's used to help diagnose typhoid fever, also known as enteric fever, and to determine if someone has had a previous typhoid infection. 
Widal test

The primary physiological effect of the auxin is to stimulate the elongation of cells in shoot. They help to initiate rooting in stem cuttings and widely used for plant propagation. They promotes flowering , for example , in pineapples. It also induces parthenocarpy.

Hagfish and lampreys are the two jawless fish that survive today from the group of agnathans, or jawless fish: 

Hagfish
These eel-like scavengers are found in oceans around the world, except for the polar regions. They have slime glands that release mucus to escape predators. Hagfish are not considered vertebrates, and are classified in their own subphylum, Myxine, within the phylum Chordata. 

Lampreys
These eel-like fish are vertebrates and have been a serious pest in the Great Lakes, where they have reduced the numbers of lake trout and other species.

Keystone species are organisms that play a critical role in the structure and function of their environment. They can be any organism, including animals, plants, bacteria, and fungi. 
Examples
Some examples of keystone species include: 
Wolves: Keep elk populations in check, which helps maintain healthy stands of trees 
Termites: Modify soil physicochemical and microbial properties by their foraging activities

Pernicious anemia is an autoimmune disease that occurs when the body is unable to absorb vitamin B12 properly
Pernicious anemia can lead to serious health problems, including: neurological complications, stomach cancer, gastrointestinal neuroendocrine tumors, and fatal anemia.

The rhabdom is a transparent, rod-like structure that is located in the center of each ommatidium, a visual unit in the compound eyes of arthropods. It is made up of microvilli, which are finger-like processes contributed by a small number of photoreceptor cells.
Light is focused onto the rhabdom by the facet lens and crystalline cone of the ommatidium. The rhabdom is connected to a set of neuronal relays by a single axon.

The link reaction is the first step of aerobic respiration and connects the glycolysis process in the cytoplasm to the Krebs cycle in the mitochondrial matrix. The reaction is catalyzed by the enzyme complex pyruvate dehydrogenase.
The reaction is simplified as: 
Pyruvate + NAD⁺ + CoA → Acetyl-CoA + NADH + CO₂ 
The link reaction is vital in respiration. The acetyl-CoA that is produced enters the Krebs cycle for further oxidation. The Krebs cycle is the primary source of energy for cells.

A-NAD+, B-Dehydrogenase,C- NADH+H+, D-CO2

A-FAD +, B-Decarboxylase, C-FADH2, D-H20 89

A-NAD+, B-Dehydrogenase, C-NADH+H+, D-H20

Animals that have a constant body temperature are called homeotherms, or warm-blooded animals: 
Homeotherms
These animals maintain a constant internal body temperature, usually within a narrow range of temperatures. They have a built-in thermostat that allows them to maintain a stable internal body temperature regardless of external influence. 
Endotherms
Another term for homeotherms, these animals are warm-blooded and maintain a constant body temperature independent of the environment. Birds and mammals are examples of endotherms.

The scientific name for the human liver fluke is Clonorchis sinensis. It's also known as the Chinese liver fluke or oriental liver fluke. 
Clonorchis sinensis is a trematode worm that infects the bile duct and gall bladder of mammals that eat fish, including humans. It's the most common human fluke in Asia and the third most common in the world.

Auxin is the plant hormone that induces the formation of root nodules in leguminous plants during nitrogen fixation
The process of forming nitrogen-fixing nodules in legumes and their symbiotic partners, rhizobia bacteria, is called nodulation. It is an energetically expensive process, so the number of nodules must be strictly regulated.

Disruptive selection is a mechanism of natural selection that favors extreme values of a trait over intermediate ones. This can happen when individuals with intermediate phenotypes are less fit than those with higher or lower phenotypes

Pedigree analysis is a method used to study the inheritance of genes in humans, including Mendelian disorders, by examining family medical history
Pedigree analysis involves collecting and interpreting a family's medical history to determine how a genetic condition is inherited. 
Mendelian disorders are genetic disorders that are caused by changes in a single gene or abnormalities in the genome. They can be seen at birth and are sometimes inherited. Examples of Mendelian disorders include Huntington's disease and cystic fibrosis.

The pericarp is the wall of the ovary that develops into the wall of the fruit. The prefix "peri-" comes from Latin and Greek and means "all around" or "enclosing"
The seeds of cycads are quite large, and are often brightly colored; red, purple, and yellow seeds are common. These colorful seeds are displayed as the cone matures and the seed-bearing leaves separate from each other; the colors attract birds and a variety of mammals which disperse the seeds.

It has the largest antherozoids in the plant world

Cyclic adenosine monophosphate (cAMP) is a second messenger molecule that plays a role in many cellular processes, including: 
Signal transmission: cAMP is a second messenger that transmits signals from receptors to targets within a cell. 
Synaptic stimulation: The brain uses cAMP to convert synaptic stimulation into stored information. 
Immune response: cAMP levels can increase in clinical situations that lead to infection. 
Light signal transduction: In Anabaena cylindrica, cAMP acts as a second messenger for light signal transduction. 
Pollen tube growth: cAMP acts as a second messenger in pollen tube growth and reorientation.

The diversity of habitats over a total landscape or geographical area is called gamma diversity.
Gamma diversity is the total species diversity in a landscape. It's also known as regional diversity. 
Gamma diversity is made up of alpha and beta diversity. Alpha diversity is the diversity of species in a given community or habitat. Beta diversity is the variability in communities due to species replacement.

The enzyme uricase, also known as urate oxidase, converts uric acid into allantoin in most mammals
In humans, the uricase enzyme is nonfunctional due to a frameshift mutation that occurred during evolution. This means that uric acid, a weak acid that is relatively insoluble, is the end product of purine metabolism in humans. 
High blood uric acid levels are associated with a number of health issues, including gout, cardiovascular disease, and diabetes. Low urate levels, on the other hand, may increase the risk of neurodegenerative diseases.

The proximal convoluted tubule (PCT) reabsorbs the majority of sodium from glomerular filtrate: 
Percentage reabsorbed: The PCT reabsorbs around 70% of the sodium filtered by the glomerulus. 
Role in blood pressure and plasma volume: The PCT's sodium reabsorption helps regulate blood pressure and plasma volume. 
Coupled with water reabsorption: Sodium reabsorption is closely linked with water reabsorption, meaning that when sodium moves, water follows. 
The PCT reabsorbs sodium through a process called tubular reabsorption. In this process, the nephron removes water and solutes from the tubular fluid and returns them to the blood.

The Broca area in the frontal lobe of the brain is the region that provides the neural circuitry for word formation
The Broca area is located in the inferior frontal gyrus of the dominant hemisphere, usually the left side. It's made up of two adjacent areas, Brodmann's areas 44 and 45, also known as the pars opercularis and pars triangularis, respectively.

Melatonin is a derivative of the amino acid tryptophan.
The process of synthesizing melatonin from tryptophan involves four enzymatic steps. Serotonin is a key intermediate in this process.

Kornberg et al. refers to the research of Arthur Kornberg and his colleagues, which led to the discovery of DNA polymerase

Three ATP molecules are produced when one molecule of pyruvic acid is converted to acetyl CoA:
Metabolization: A three-carbon atom pyruvic acid molecule is metabolized to produce a two-carbon atom acetyl CoA molecule.
Oxidative decarboxylation: A carbon dioxide molecule is released from the pyruvic acid molecule.
Electron transport chain: Three ATP molecules are produced when a reduced coenzyme molecule is oxidized in the electron transport chain. 
Pyruvic acid is the end product of glycolysis, which is the process of partially oxidizing glucose into two pyruvic acid molecules. Acetyl CoA is a molecule that delivers the acetyl group to the citric acid cycle, where the acetyl group is oxidized to produce energy.

The Haldane effect is a physicochemical phenomenon that occurs when hemoglobin has a lower oxygen saturation. In this state, hemoglobin has a higher affinity for CO2 and can bind more of it. When the blood becomes oxygenated in the lungs, the CO2 dissociates from the hemoglobin and is removed from the body.

When an allergen enters the body, it binds to IgE antibodies on the surface of mast cells and basophils. This sensitizes the cells to release histamine and other inflammatory mediators when they encounter the allergen again.

Cycas: Has large, spirally twisted male gametes with cilia. Cycas is a gymnosperm with multiciliate male gametes. 
Funaria: A bonfire moss with biflagellate male gametes. Funaria reproduces sexually through male and female gametangia. 
Pteris: Does not have flagellated male gametes. 
Flagellated male gametes are also known as zoids. They are usually found in lower plants such as bryophytes, pteridophytes, algae, and certain gymnosperms.

Submerged hydrophytes, or aquatic plants that are completely submerged, have stomata that are either absent or vestigial. Instead of stomata, the surface cells of these plants absorb water, nutrients, and dissolved gases from the water.

The progressive decrease of helper T cells is a hallmark of HIV-1 infection and a key factor in the development of AIDS.
The CD4 cell count is a laboratory test that measures the number of helper T cells in the body. It's used to monitor the effectiveness of antiretroviral treatment (ART) and to stage the disease.

Apomixis is a process of asexual reproduction in plants that allows for the formation of seeds without fertilization or meiosis

Daniel I. Arnon (1910 - 1994) was a plant physiologist and a leading researcher in photosynthesis who discovered the process of photophosphorylation
Arnon and his colleagues discovered that light energy is converted into chemical energy through the production of ATP in illuminated spinach chloroplasts. This process is called photophosphorylation

Black Mann - Dark reaction of Photosynthesis

Daniel Arnon - Photosynthetic photophosphorylation

Underground Stem Modifications
As the name suggests, these are present underground. They serve various purposes such as storage of food, propagation and perennation. They can be identified from roots by the presence of nodes and internodes. They help in propagation through asexual reproduction and help the plant survive a period of dormancy. They provide protection from grazing by animals and environmental stress.

Rhizome – It runs parallel to the ground, the upper portion can produce scaly leaves and the bottom portion can give rise to adventitious roots. They contain, nodes, internodes and buds.
They store food.Examples: Ginger, turmeric.Banana contains rootstock, which is rhizome growing vertically.
Bulb – Stem is reduced and surrounded by scale leaves, modified bulbs can be seen.Examples: Tulips, Lilies, Daffodils, Onion, Garlic
Corm – It is a short upright stem, covered with scaly leaves. It is hard as compared to bulbs.Examples: Colocasia, Yam, Saffron
Tuber – Here the terminal of the stem is fleshy and stores food. The stem contains nodes and internodes but due to swelling, they are not very distinct. Presence of scaly leaves at nodes can be seen as eyes or scars.Examples: Potato, Artichokes

The Out-of-Africa model is a hypothesis that explains the origin and spread of modern humans:
Origin: Modern humans, or Homo sapiens sapiens, evolved in East Africa.
Migration: Around 70,000–100,000 years ago, modern humans migrated out of Africa and replaced archaic human populations around the world.
Genetic variation: Most genetic variation in humans is found in Africa, suggesting that humans evolved there for the longest time.

Secondary phloem is a complex tissue in plants that's involved in transporting sugars and is found in gymnosperms and dicotyledons

The palmella stage is a short-term, asexual reproduction stage in some algae, such as Chlamydomonas and Ulothrix, that occurs when conditions are unfavorable. During this stage, the algae cells divide repeatedly to form daughter protoplasts, which then surround themselves with a gelatinous wall. The daughter protoplasts are called palmellospores. The parent cell wall also gelatinizes, creating a mucilage capsule that encloses all the daughter protoplasts. This capsule resembles a large colony, and is named after the algae Palmella because early researchers thought it was a separate species.

The incorporation of two or more major genes in a host for specific resistance to a pathogen is called vertical resistance

Seed mixture of isolines, related lines or unrelated lines

Incorporation of two or more major genes in the host for specific resistance to a pathogen

Planned/strategic use of major genes in the development of resistant cultivars for various geographical areas

Individual major genes is transferred into the well adapted cultivar through back crossing

Hyaluronidase is an enzyme that breaks down hyaluronic acid, a substance that gives fluids in the body a jelly-like consistency. Hyaluronidase is used in medicine to help drugs and fluids be absorbed by the body

The punctuated equilibrium hypothesis was proposed by Stephen Jay Gould and Niles Eldredge in 1972. Their paper, titled Punctuated Equilibria: An Alternative to Phyletic Gradualism, described how the history of life is characterized by periods of stability followed by bursts of evolutionary change.

A parasitic food chain is a type of food chain where food energy is transferred from larger organisms to smaller organisms without killing. In this type of food chain, the larger animals are known as the hosts and the smaller organisms that get nutrition from the hosts are known as the parasites. 
Inverted pyramid of numbers: The pyramid of numbers in a parasitic food chain is inverted, meaning that the number of individuals is greatest at the top trophic level (hyperparasites).

India has four officially recognized biodiversity hotspots:
The Himalayas
Spanning several Indian states and neighboring countries, the Himalayas are known for their diverse ecosystems.
The Western Ghats
Located along India's western coast, the Western Ghats are home to a variety of habitats and endemic species.
The Indo-Burma region
This region in northeastern India is home to lush tropical forests and high levels of endemism.
The Sundaland
The Andaman and Nicobar Islands in the Bay of Bengal contribute to the Sundaland hotspot.

Ferredoxin is a protein that transfers electrons in many metabolic reactions.
Ferredoxin is a small, acidic protein that contains iron and sulfur atoms in iron–sulfur clusters. These clusters can accept or release electrons, changing the oxidation state of the iron atoms.

Ubisch bodies found in tapetal cells help in the formation of exine, which is one of the two main layers that form the outer layer of pollen grains.
When the anther is young, the tapetum cells contain spherical bodies called pro-ubisch bodies. These bodies increase in number through meiosis in pollen mother cells.

involve in the external thickening of exine

provide nourishment to developing pollens

Scarification is a process that weakens, opens, or alters the seed coat to encourage germination. It can be done mechanically, thermally, or chemically. 
Scarification is used for plant species that are impervious to water and gases. The seed coat of many plants is tough and provides mechanical resistance to the growth of the embryos. Scarification breaks seed dormancy and promotes germination.

The 1972 United Nations Conference on the Human Environment, also known as the Stockholm Conference, was the first major UN conference to focus on international environmental issues. The conference was held in Stockholm, Sweden from June 5–16, 1972.

World Summit on Sustainable Development -2002

The enzyme ATP synthase is made up of two parts, F1 and Fo, with Fo being integral and F1 being a peripheral membrane protein complex:
F0
A transmembrane channel that allows protons to pass through the mitochondrial membrane. It's embedded in the inner membrane and forms a proton turbine.
F1
A peripheral membrane protein complex that protrudes into the mitochondrial matrix. It contains the catalytic sites for ATP synthesis.

The golden toad (Incilius periglenes) is an extinct species of true toad that was once abundant in a small, high-altitude region of about 4 square kilometres (1.5 sq mi) in an area north of the city of Monteverde, Costa Rica. It was endemic to elfin cloud forest.Also called the Monte Verde toad, Alajuela toad and orange toad, it is commonly considered the "poster child" for the amphibian decline crisis. This toad was first described in 1966 by herpetologist Jay Savage.The last sighting of a single male golden toad was on 15 May 1989, and it has since been classified as extinct by the International Union for Conservation of Nature (IUCN).

During absorption, water moves from soil to the root which means the water potential of cell sap of root is lower than that of soil. Thus, the cell sap will have a water potential lower than the pure water and soil solution during absorption.

Pure water, but higher than that of soil solution

Soil solution, but higher than that of pure water

Gluconeogenesis is a metabolic process that produces glucose from non-carbohydrate carbon substrates. It's a vital process that helps maintain blood glucose levels during fasting or vigorous exercise, when glycogen stores are depleted.

Teaching aids are important because they: Foster conceptual thinking, Foster an engaging learning environment, Make learning permanent, and Give students hands-on experience.

the goal of teaching is to create desirable changes in the behavior of students. Teaching is a goal-directed process that aims to impart learning and help students master new skills, concepts, and principles. 
Teaching is a comprehensive process that involves communication, mutual interaction, and sharing of ideas, values, skills, information, and knowledge with students. It includes both training and instruction, but is different from them.

A vivarium is a closed-off space that provides a stable environment for plants and animals to be observed or studied. It can be a mini ecosystem that mimics a desert, jungle, or fairy garden.

A syllabus is a detailed outline of a course or subject, while a curriculum is an instructional program that helps students achieve their goals. A syllabus is a subset of the curriculum, and focuses on the specific details of a particular course. 
A syllabus is typically provided at the beginning of a term, and is a common tool used by teachers to evaluate students. It can be prepared by the instructor or an examination board.

Curriculum is same in all educational institutions affiliated to a particular university

Curriculum is a sub component of a syllabus

The main difference between a diagnostic test and an achievement test is their purpose: 
Diagnostic test
Used to identify a student's strengths and weaknesses before instruction, and to help teachers plan accordingly. Diagnostic tests are taken before a learning experience. 
Achievement test
Used to measure a student's level of understanding or accomplishment in a specific area of learning. Achievement tests can be formal standardized tests or informal checks for understanding.

Gives due weightage to every topic in the content area

Gives greater emphasis to the aspects with potential difficulties

Achievement testing is a process that measures a person's knowledge or skills in a specific area. Achievement tests are often used to assess learning after teaching, and can help identify a student's academic strengths and weaknesses.

The psychomotor domain includes physical movement, coordination, and use of the motor-skill areas. Development of these skills requires practice and is measured in terms of speed, precision, distance, procedures, or techniques in execution.

The split-half method is a way to estimate the reliability of a test by randomly splitting it into two halves and calculating the correlation between the two halves. The closer the correlation between the two halves, the higher the reliability of the test.

A teacher's diary is a tool that teachers use to record their thoughts and what happens in their classes. Teachers can use their diaries to: 
Improve their teaching: Teachers can record what happened in a class, identify the causes, and consider how to improve the class. 
Increase accountability: Teachers can record activities and anecdotes that occur in the classroom. 
Become better prepared: Teachers can use their diaries to prepare for class, which can lead to better teaching quality. 
Organize their work: Teachers can use their diaries to organize their teaching work.

It equips the teacher with sufficient theoretical knowledge

It helps teachers to adopt appropriate methods and approaches of teaching

It helps teacher to prepare various instructionalmaterials

It provides self learning and self assessment for students

D. S. Kothari was president of the Indian Science Congress at its golden jubilee session in 1963. He was elected President of Indian National Science Academy in 1973. His research on statistical thermodynamics and his Theory of White Dwarf Stars gave him an international reputation.

Continuous and Comprehensive Evaluation (CCE) is a student assessment system that evaluates a student's development throughout the school year. It was introduced in India by the Central Board of Secondary Education (CBSE) to help students reduce stress and improve their overall development.

Evaluation at the end of the particular course

Observation methods in teaching can involve observing students or teachers, and can be used for a variety of purposes: 
Student observation
Teachers can observe students working and take informal notes on their performance and abilities. For example, a teacher might observe a student struggling with multiplication problems and help them improve their process. 
Teacher observation
Teachers can observe other teachers' classes to learn and reflect. This can help teachers discover new teaching methods and improve their instructional skills. 
Formative observations
These lower-stakes observations can be used to share ideas, get feedback, and improve teaching practice. 
Summative observations
These observations are typically part of a formal review process and are used for performance reviews or instructor promotions.

The field trip method of teaching is an educational approach that takes learning outside of the classroom to provide students with real-world experiences. Field trips can be a student-centered way to help students connect their classroom learning to real-life applications.

The domains coming under Mc Cormack and Yager's taxonomy are, Knowing and understanding (Knowledge Domain) Exploring and discovering (Process Domain),Imaging and Creating (Creativity Domain),Using and Applying (Application Domain), Feeling and valuing (Attitude domain).

Multimedia approach consists of the appropriate and effective selection and usage of different media in such a combination to reach the teaching-learning objectives in the best possible manner.

' Advance organizer'
A cognitive instructional strategy that helps students learn and retain new information. It's a presentation of information that acts as an umbrella for new material.

Helen Parkhurst created the Dalton Plan, an educational model, in the 1920s. The plan is based on the idea that children are naturally motivated to learn when they are responsible for their own learning. The Dalton Plan's objectives include:
Tailoring each student's program to their needs, interests, and abilities
Promoting independence and dependability
Enhancing the student's social skills and sense of responsibility toward others

An essay type question is a test item that asks students to create a written response, such as an argument, explanation, or exploration of a topic. They are also known as long answer questions.

Possess sufficient validity and reliability

Programmed learning is a research-based instructional method that presents information in small, logical steps with immediate feedback. It's based on the theory of operant conditioning, which states that learning is most effective when it's broken down into small steps and reinforced immediately.

A year plan, also known as a curriculum map, is a structured outline of what will be taught and learned during an academic year. It helps teachers, students, and parents understand the lessons and activities that will take place.

The ZPD is a key concept in the theory of learning and development of psychologist Lev Vygotsky. It refers to the gap between what a learner can do on their own and what they can do with help from a more knowledgeable peer or adult.

Curriculum makers face challenges when the nature of the student population is changing because of the need to adapt curriculum development frameworks and approaches to new systems.

The nature of the student population is changing

The deductive method of science teaching is a top-down approach that involves presenting a general concept and then providing specific examples to illustrate how it applies.

Planning is the first and most important step in effective teaching: 
Define learning objectives: Determine what you want students to learn and be able to do by the end of the lesson. 
Get to know your students: Learn about their backgrounds, learning styles, hobbies, skill levels, and any special needs. 
Research the topic: Research the topic as defined by your objectives. 
Organize the material: Analyze the content into its elements and arrange them in a logical sequence. 
Select instructional methods: Choose the appropriate instructional method. 
Prepare the lesson: Prepare the beginning and ending of the lesson, and choose appropriate support material.

An episcope, also known as an opaque projector, is used to project images of opaque objects.
An episcope uses a bright lamp to shine light onto an opaque object from above. A system of mirrors, prisms, and lenses then focuses the image onto a screen.

Opaque objects as well as Transparent objects

LEARNING TO KNOW: to provide the cognitive tools required to better comprehend the world and its complexities, and to provide an appropriate and adequate foundation for future learning.

The laboratory method of teaching is a hands-on approach to learning that involves students conducting experiments in a laboratory setting. It's primarily used in science and mathematics.

The project method of teaching, also known as project-based learning (PBL), is an instructional strategy that engages students in real-world projects to help them learn.

KIET: Kerala Infrastructure and Technology for Education (KITE) is a state-owned special purpose company under the education department of the Government of Kerala. It was developed to support ICT-enabled education for schools in Kerala.

BSCS Science Learning, formerly known as Biological Sciences Curriculum Study (BSCS), is an educational center that develops curricular materials, provides educational support, and conducts research and evaluation in the fields of science and technology.

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