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Find the best class 10 science sample paper at Studymate that can help students to excel in their board exams. These study materials help students to improve their weaker areas in the aforementioned subject. Visit https://bit.ly/33h4Yxn
9th science sample pape for summative assessment-1APEX INSTITUTE
APEX INSTITUTE has been established with sincere and positive resolve to do something rewarding for ENGG. / PRE-MEDICAL aspirants. For this the APEX INSTITUTE has been instituted to provide a relentlessly motivating and competitive atmosphere.
Class 3 CBSE Environmental Studies Sample Paper Term 1 Model 2Sunaina Rawat
Cbse Class 3 Environmental Studies Sample Paper Term 1 Model 2 - http://cbse.edurite.com/cbse-sample-papers/sample-papers-for-class-3-cbse-social-science.html
Find the best class 10 science sample paper at Studymate that can help students to excel in their board exams. These study materials help students to improve their weaker areas in the aforementioned subject. Visit https://bit.ly/33h4Yxn
9th science sample pape for summative assessment-1APEX INSTITUTE
APEX INSTITUTE has been established with sincere and positive resolve to do something rewarding for ENGG. / PRE-MEDICAL aspirants. For this the APEX INSTITUTE has been instituted to provide a relentlessly motivating and competitive atmosphere.
Class 3 CBSE Environmental Studies Sample Paper Term 1 Model 2Sunaina Rawat
Cbse Class 3 Environmental Studies Sample Paper Term 1 Model 2 - http://cbse.edurite.com/cbse-sample-papers/sample-papers-for-class-3-cbse-social-science.html
I got a question in web site https://www.entrancei.com can anyone help me to ...entrancei
A balloon containing 1 mole air at 1 atm initially is filled further with air till pressure increases to 4 atm. The initial diameter of the balloon is 1 m and the pressure at each stage is proportional to diameter of the balloon. How many moles of air added to change the pressure from 1 atm to 4 atm.
Grooming at the APEX INSTITUTE is done methodically focusing on understanding of the subject, tricks of tackling the questions and above all enthusing students with self confidence, ambition and a 'never say give up' spirit. As secrets of success these are no substitutes for hard work and patience. These qualities, the APEX INSTITUTE ensures will be developed in students in full measure perhaps luck plays some role in one's life and career. But it is also a universal truth that before proper grasps of subject. Intelligent preparation and perservance even adverse luck does not stand a chance.
With this mantra success is sure to come your way. At APEX INSTITUTE we strive our best to realize the Alchemist's dream of turning 'base metal' into 'gold'
GENERAL INSTRUCTIONS This final examination is worth 100 points.docxbudbarber38650
GENERAL INSTRUCTIONS: This final examination is worth 100 points. There are 3 sections: Multiple choice (40 points), Problems (24 points), and essay (36 points) sections.
Read all instructions carefully.
* Do not leave any required questions blank. Make your best guesses.*
**When answering questions for all sections, use the accompanying Answer Sheet. Submit the Answer Sheet document to your Assignment Folder before or on the due date.**
**
MULTIPLE CHOICE SECTION INSTRUCTIONS: Read all instructions carefully. Please answer all questions. Each question is worth 1 points. The Multiple Choice section is worth 40 points.
**Do not enter your answers here.** Type in the letter you select as the best answer on the Answer Sheet provided by your instructor.
1] In the scientific method, a hypothesis is _____.
A ) is a statement of fact
B ) makes a prediction that can be tested
C ) is usually proven to be correct
D ) can only be tested once
E ) all of these
[2] Which of the following can be considered a definition of "theory?"
A ) A theory can be an explanation of scientific laws.
B ) A theory is an integrated explanation of numerous hypotheses, each supported by a large body of observations and experiments.
C ) A theory is a condensation and simplification of many data that previously appeared unrelated.
D ) A theory is a prediction for new data suggesting new relationships among a range of natural phenomena.
E ) All of the above.
[3] An integrated explanation of numerous hypotheses is known as a _____.
A ) fact
B ) law
C ) control
D ) theory
E ) guess
[4] What is the correct sequence of steps in the scientific method?
I. State a problem
II. Analyze and interpret data
III. Develop a hypothesis
IV. Share the results with other scientists
V. Design and perform experiment to test the hypothesis
A ) I – II - III - IV – V
B ) III – I - V – II – IV
C ) V – IV – III – II – I
D ) I – III – V – II – IV
E ) V – II – I – III - IV
[5] The law of conservation of energy states that in the absence of external work input or output, _____.
A ) energy cannot be created or destroyed
B ) momentum cannot be created or destroyed
C ) mass cannot be created or destroyed
D ) energy can be created and then destroyed
[6] That family of elements that is highly nonreactive is called the _____.
A ) alkaline earth family
B ) transition metals
C ) alkali metal family
D ) rare gas family
[7] The role of a catalyst is to _____.
A ) speed up a chemical reaction
B ) slow down a chemical reaction
C ) act as a reactant in a chemical reaction
D ) serve as a product in a chemical reaction
[8] Ocean water has a pH around 8.2. Identify the correct statement.
A ) Ocean water is neither acidic nor basic.
B ) Ocean water is slightly acidic.
C ) Ocean water is slightly basic.
D ) Ocean water has a neutral pH.
[9] During an _____ reaction, _____.
A ) exothermic; energy is released
B ) endothermic; energy is absorbed
C ) both are corre.
APEX INSTITUTE was conceptualized in May 2008, keeping in view the dreams of young students by the vision & toil of Er. Shahid Iqbal. We had a very humble beginning as an institute for IIT-JEE / Medical, with a vision to provide an ideal launch pad for serious JEE students . We actually started to make a difference in the way students think and approach problems.
Sample paper of science for class 9 will help assess the preparation of the student and enable them to gain insights into their strength and weakness. Based on the same, students can plan their revision strategy accordingly.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
The increased availability of biomedical data, particularly in the public domain, offers the opportunity to better understand human health and to develop effective therapeutics for a wide range of unmet medical needs. However, data scientists remain stymied by the fact that data remain hard to find and to productively reuse because data and their metadata i) are wholly inaccessible, ii) are in non-standard or incompatible representations, iii) do not conform to community standards, and iv) have unclear or highly restricted terms and conditions that preclude legitimate reuse. These limitations require a rethink on data can be made machine and AI-ready - the key motivation behind the FAIR Guiding Principles. Concurrently, while recent efforts have explored the use of deep learning to fuse disparate data into predictive models for a wide range of biomedical applications, these models often fail even when the correct answer is already known, and fail to explain individual predictions in terms that data scientists can appreciate. These limitations suggest that new methods to produce practical artificial intelligence are still needed.
In this talk, I will discuss our work in (1) building an integrative knowledge infrastructure to prepare FAIR and "AI-ready" data and services along with (2) neurosymbolic AI methods to improve the quality of predictions and to generate plausible explanations. Attention is given to standards, platforms, and methods to wrangle knowledge into simple, but effective semantic and latent representations, and to make these available into standards-compliant and discoverable interfaces that can be used in model building, validation, and explanation. Our work, and those of others in the field, creates a baseline for building trustworthy and easy to deploy AI models in biomedicine.
Bio
Dr. Michel Dumontier is the Distinguished Professor of Data Science at Maastricht University, founder and executive director of the Institute of Data Science, and co-founder of the FAIR (Findable, Accessible, Interoperable and Reusable) data principles. His research explores socio-technological approaches for responsible discovery science, which includes collaborative multi-modal knowledge graphs, privacy-preserving distributed data mining, and AI methods for drug discovery and personalized medicine. His work is supported through the Dutch National Research Agenda, the Netherlands Organisation for Scientific Research, Horizon Europe, the European Open Science Cloud, the US National Institutes of Health, and a Marie-Curie Innovative Training Network. He is the editor-in-chief for the journal Data Science and is internationally recognized for his contributions in bioinformatics, biomedical informatics, and semantic technologies including ontologies and linked data.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
1. CBSE
Class IX Science
Time: 3 hrs Total Marks: 90
General Instructions:
1. The question paper comprises of two sections, A and B. You are to attempt both the
sections. All questions are compulsory.
2. All questions of Section A and all questions of Section B are to be attempted
separately.
3. Question numbers 1 to 3 in Section A are one mark questions. These are to be
answered in one word or in one sentence.
4. Question numbers 4 to 6 in Section A are two marks questions. These are to be
answered in about 30 words each.
5. Question numbers 7 to 18 in Section A are three marks questions. These are to be
answered in about 50 words each.
6. Question numbers 19 to 24 in Section A are five marks questions. These are to be
answered in about 70 words each.
7. Question numbers 25 to 33 in Section B are multiple choice questions based on
practical skills. Each question is a one mark question. You are to select one most
appropriate response out of the four provided to you.
8. Question numbers 34 to 36 in Section B are questions based on practical skills and
are two marks questions.
SECTION A
Attempt all questions from this section.
1. Give one example where kinetic energy is transferred from one object to another.
2. What are polyatomic ions?
3. What are the different states in which water is found during the water cycle?
[1]
[1]
[1]
4. Flash and thunder are produced simultaneously. Yet, thunder is heard a few seconds
after the flash is seen, why? How does the speed of sound in air vary with the rise in the
density of the medium?[2]
5. Explain the term variable valency with the help of two examples.
6. Write two points of differences between gymnosperms and angiosperms.
7.
[2]
[2]
[3]
(a) Draw a diagram depicting low pitched sound and high pitched sound.
(b) When a person uses deodorant spray, the other person standing at a distance would
hear the sound of spraying first and the fragrance of the spray would reach him
later. Why so?
8. [3]
(a) An object 'P' of mass ‘m’ is lifted from a point A on the ground to point B at a height
'h' above the earth by Rina and Mita, but the path taken by both of them for doing it
is different (as shown in fig. I and II). Calculate the work done in both the situations.
(b) In the above given cases, which force is doing positive work and which one is doing
negative work?
9. What is SONAR? For what is it used? Explain its working in brief.
10. Define work. Under what conditions, work is said to be done by a force on an object?
[3]
11. State three conditions necessary for hearing sound.
12. Calculate the number of molecules of sulphur present in 16 g of solid sulphur.
13.
(a) If an element ‘M’ has mass number 27 and atomic number 13, how many protons
and neutrons does its atom contain? What valency will be shown by M?
(b) Write the electronic configuration of an atom with atomic number 6.[3]
[3]
[3]
[3]
2. 14. Write a short note on greenhouse effect.
15. Give two examples of each of the following:
(a) Diseases which spread through air.
(b) Diseases which spread through water.
(c) Diseases which spread through insects.
[3]
[3]
16. What precautions can you take in your school to reduce the incidence of infectious
diseases? Mention any three points.[3]
17.
(a) List any two benefits of classification.
(b) Why bryophytes and pteridophytes grow in moist and shady places?
18. What are the effects of air pollution on human beings?
19.
[3]
[5]
(a) Define kinetic energy. Give examples.
(b) Obtain an expression for the kinetic energy of an object of mass 'm' and possessing a
velocity 'v'.
20. Draw a labeled diagram of auditory parts of the human ear and explain how the human
ear works.[5]
21. Define electrovalency and covalency. Describe the formation of a covalent bond with
the help of an example.[5]
22.
(a) Describe oxygen cycle with the help of a diagram.
(b) How does depletion of the ozone layer take place?
23.
(a) Define the following terms:
i. Lichens
ii. Cryptogamae
iii. Phanerogams
(b) Why whales are not grouped in fishes?
(c) What is bilateral symmetry?
24.
(a) How cholera is spread through water?
(b) What is an antibiotic? Give one example
[5]
[5]
[5]
[3]
3. SECTION B
25. Reverberation produced in large auditoriums is due to:
(a) Reflection of sound by windows.
(b) Absorption of sound by walls.
(c) Reflection of sound by walls and ceiling.
(d) Absorption of sound by floor.
[1]
26. Water meniscus in a graduated cylinder is of concave shape. While finding the volume,
the correct reading will correspond to:[1]
(a) The upper end of the meniscus
(b) The lower end of the meniscus
(c) The midpoint of the meniscus
(d) Anywhere on the meniscus
27. While determining the density of the material of a sphere using a spring balance and a
measuring cylinder, a student noted the following readings:[1]
i. Mass of the sphere = 81 g
ii. Reading of water level in the cylinder without the sphere in it = 54 ml
iii. Reading of water level in the cylinder with the sphere in it = 63 ml
On the basis of these observations, the density of the material of the sphere is:
(a) 1500 kg m-3
(b) 6000 kg m-3
(c) 7000 kg m-3
(d) 9000 kg m-3
28. A student lowers a solid in a container filled with a liquid. He finds that there is
maximum apparent loss in the weight of the solid when:[1]
(a) It just touches the surface of the liquid.
(b) It is completely immersed in the liquid.
(c) It is partially immersed in the liquid.
(d) It is partially immersed and also touches the sides of the container.
29. An object exerts a force ‘F’ on a surface of surface area ‘A’. The pressure ‘P’ acting on the
surface is given by:[1]
(a) P = F/A
(b) P = A/F
(c) P = FA
(d) P = F/A2
4. 30. In the experiment of verification of reflection of sound, the incident sound is directed
along:[1]
(a) The axis of the tube.
(b) The normal to the axis of the tube.
(c) an angle of 30o from the axis of the tube.
(d) an angle of 45o from the axis of the tube.
31. In the figure of the earthworm given below, the horizontal lines throughout the body
represent the:[1]
(a) Cells of the body.
(b) Cell walls separating the cells of the body.
(c) Vertically arranged muscles of the body.
(d) Septa separating the segments of the body
32. The characteristic features to identify a nerve cell are:[1]
(a) Round or oval cells with a blobbed nucleus and cytoplasmic granules.
(b) Cell body with branched cytoplasmic extensions at one end and a long projection at
the other end.
(c) Spindle shaped cell with a big central nucleus.
(d) Red colored, biconcave disc shaped enucleated cells.
33. According to the law of conservation of mass, mass of reactants will be equal to the
mass of:[1]
(a) Products
(b) Catalysts
(c) Gases evolved
(d) Apparatus used for reaction
5. 34. The feature which places them in the same phylum is: [2]
(a) Pointed head
(b) Bulky thorax
(c) Presence of scales
(d) Post anal tail
35. 6.4 g of MgCO3 on heating gave 2.88 g of MgO and 3.52 g of CO2. What will be the total
mass of the products? Which law of chemical combination will govern your answer?
Which law of chemical combination governs this? Explain the law.[2]
36. A student while verifying the laws of reflection of sound measured the angle between
the incident sound wave and the reflected sound wave as 110o. What will be the angle of
reflection? State the law of reflection of sound which was used to obtain the angle of
reflection.[2]
6. 34. The feature which places them in the same phylum is: [2]
(a) Pointed head
(b) Bulky thorax
(c) Presence of scales
(d) Post anal tail
35. 6.4 g of MgCO3 on heating gave 2.88 g of MgO and 3.52 g of CO2. What will be the total
mass of the products? Which law of chemical combination will govern your answer?
Which law of chemical combination governs this? Explain the law.[2]
36. A student while verifying the laws of reflection of sound measured the angle between
the incident sound wave and the reflected sound wave as 110o. What will be the angle of
reflection? State the law of reflection of sound which was used to obtain the angle of
reflection.[2]