NAS2 Challenge Exam Questions and Answers (With Correct Solutions) Latest 2023

NAS2 Challenge Exam Questions and Answers (With
Correct Solutions) Latest 2023
Purpose of Scientific Method – correct answer ✅solve a problem or answer a
question
Question, Hypothesis, Experiment, Observe & Record, Analyze, Conclude – correct
answer ✅steps of scientific method
Independent variable – correct answer ✅a variable that stands alone and isn’t
changed by the other variables you are trying to measure, change or controlled
example: age
dependent variable – correct answer ✅a variable dependent on other factors,
tested or measured
example: test score – factors that go into a score you receive on a test
control group – correct answer ✅does not receive treatment and used to
compare or measure the other subjects

NAS2 Challenge Exam Questions and Answers (With
Correct Solutions) Latest 2023
experimental group – correct answer ✅exposed to changes in independent
variable
anatomy – correct answer ✅branch of science concerned with bodily structure of
living organisms; structure
physiology – correct answer ✅science dealing with the functions of living things
or their organs
level of organization – correct answer ✅living things arranged from the simplest
to most complex are:
organelle
cells
tissues
organs
organ systems, organism
populations communities
ecosystem
biosphere

NAS2 Challenge Exam Questions and Answers (With
Correct Solutions) Latest 2023
requirements for life – correct answer ✅Cellular organization
Reproduction
Metabolism
Homeostasis
Heredity
Response to stimuli
Growth and development
Adaptation through evolution
survival needs – correct answer ✅Food, oxygen, water, body temperature,
atmospheric pressure (oxygen/carbon dioxide exchange)
homeostasis – correct answer ✅relatively constant internal physical and chemical
conditions that organisms maintain
receptor – correct answer ✅senses environmental stimulus and sends info to
control center
control center – correct answer ✅hypothalamus
signals effector

What is the purpose of the scientific method

to clearly do an experiment by process of steps helping you keep track and correct any mistakes and to show others how you got to the result that you achieved in conclusion

Identify the purpose of the scientific method

1.Ask a question
2.Do Background research
3 Construct a hypothesis
4.test your hypothesis by doing an experiment
5 analyze your data and draw a conclusion
6. Communicate your results

What is the difference between an independent variable and and dependent variable

Value of an independent can be changed. You cannot change the value of dependent variable. the independent variable is the value which is manipulated in an experiment. The dependent variable is compared to the control group, which does not recieve the test variable

Anatomy

The study of structure and shape of the body and its parts and relation to one another

Physiology

Study of how the body and its parts work or function

Six Levels of organization

1. Chemicals (atoms and molecules)
2. Cellular
3. Tissue
4. Organ
5. Organ system
6. Organismal

Identify Requirements for Life

The ability to :maintain one’s boundaries, move ,respond to stimuli,digest food, metabolize,excrete waist,reproduce,grow

Identify survival needs

1. Nutrients
2. Oxygen
3. Water
4. Appropriate temperture
5. Appropriate atmospheric pressure

Homeostasis

A balance in which internal conditions change and very but always within relatively narrow limits

Basic Mechanism for homeostasis (receptor, control center, etc)

Negative feedback mechanism

Negative feedback mechanism

Works to shut off original stimulus or reduce its intensity

Positive feedback mechanism

tend to increase the original stimulus

Anatomical Position

the body is erect with the feet parallel and the arms hanging at the side with palms facing forward

Superior (Cranial/Cephalid)

Toward the head end or upper part of the structure;above

Dorsal/Posterior

Toward the backside of the body;behind

Proximal

Close to the origin of a body part or the point of attachment of a limb to the body trunk

Thoracic

chest

Cervical

Neck region

Gluteal

buttock

Major planes of dissection

1. Sagittal(left/right)
2. Frontal/Coronal (back/front)
3 Transverse (top/bottom)

Identify body’s major cavities and their contents

• Dorsal/posterior – toward or at the backside of the body; behind
• Ventral/Anterior- Toward or at the front of the body; in front of

Atomic structure

The dense central nucleus contains the protons and neutrons, while the electrons orbit around the nucleus much like plants do the sun

Symboligy

study of interoperation of symbols

Ionic bonds

Form when electrons are completely transferred from one atom to another

Covalent Bonds

Form when two atoms share electrons from their valance shells

Hydrogen Bonds

form when a hydrogen atom is attracted by one electrons hungry nitrogen or oxygen atom is attracted by another electrons hungry atom and the hydrogen atoms forms a bridge between them this is an extremely weak bond

Non-polar bonds

share their electrons equally

Polar Covalent Bonds

do not share electrons equally causing there to be 2 charged poles

Enzymes

Bind and HOld the reacting molecules(the substrates) in the proper position for chemical interaction

Substrate

Bound to enzyme’s active site they undergo structural changes that result in a new product. Once the reaction has occurred the enzyme releases product

Decomposition reactions

occur when a molecule is broken down into smaller molecules; AB —> A + B

Synthesis Reactions

occur when two or more atoms or molecules combine to form a larger more complex molecule; A + B —> AB

Exchange reactions

occur when a switch is made between molecule parts and different molecules are made; AB + DC —> AD + CB

Enzyme Catalyze Chemical Reactions

Enzymes bind and “hold” the reacting molecules (the substrates) in the proper position for chemical interaction. While the substrates are bound to the enzyme’s active site, they undergo structural changes that result in a new product. Once the reaction has occurred, the enzyme releases the product.

Waters Role In Life

•Reduces temperature fluctuations
•Acts as a solvent for sugars, salts, and other solutes
•Important reactant in chemical reactions
• Acts as a transport medium
•Forms a cushion around the brain that helps protect it from physical trauma

pH Scale

The symbol for hydrogen ion concentration; a measure of the relative acidity or alkalinity of a solution (pH lower than 7 is acidic; pH higher than 7 is alkaline)

Organic Compound

compounds in the body containing carbon

Monomer

are small molecules, mostly organic, that can join with other similar molecules to form very large molecules, or polymers. All monomers have the capacity to form chemical bonds to at least two other monomer molecules.

Polymer

are a class of synthetic substances composed of multiples of simpler units called monomers. Polymers are chains with an unspecified number of monomeric units.

Four Major Groups Of Organic Compounds

1. Carbohydrates
2. Lipids
3. Proteins
4. Nucleic ACids

Cell Theory

•All organism are made of one or more cells
•the cell is the fundamental unit of life
•all cells come from preexisting cells
•all cell have the same basic chemical composition
•all cells use energy
•all cells contain dna that is duplicated and passed on as each cell divides