NES 103 Science

Question 1

Homeostasis

Answer 1

All living organisms exhibit homeostasis, or the ability to maintain a state of internal balance. For example, if the environmental temperature increases, the human body begins to perspire, and the cooling effect of evaporation decreases the surface temperature of the skin. Likewise, a disruption in any system will set off a diverse set of control mechanisms that return the organism to a state of internal balance.

Question 2

Energy

Answer 2

Every living thing needs energy that they produce or acquire in order to exist, grow, and reproduce. Some organisms (called autotrophic organisms) are capable of harnessing energy from sunlight and using it to produce glucose, the main source of energy for the organism. Others (called heterotrophic organisms) capture energy by eating plants or other animals.

Question 3

autotrophic organisms

Answer 3

are capable of harnessing energy from sunlight and using it to produce glucose, the main source of energy for the organism.

Question 4

heterotrophic organisms

Answer 4

capture energy by eating plants or other animals.

Question 5

organelles

Answer 5

are specialized to fulfill specific functions within the cell. Mitochondria, for example, break down glucose to provide energy to the cell. Bacterial cells lack most of these organelles.

Question 6

Mitochondria

Answer 6

break down glucose to provide energy to the cell.

Question 7

Four basic types of tissues Humans have

Answer 7

connective, epithelial, muscle, and nerve.

Question 8

epithelial

Answer 8

of or belonging to epithelium

Question 9

epithelium

Answer 9

membranous tissue covering internal organs and other internal surfaces of the body

Question 10

The human body has ___organ systems. Name them

Answer 10

11 systems
Circulatory
Digestive
Endocrine
Excretory
Immune
Integumentary
Muscular
Nervous
Reproductive
Respiratory 
Skeletal

Question 11

Vascular plants have a stystem of tubes (____ _____ ______) that are used to transport nutrients and water

Answer 11

xylem and phloem

Question 12

chlorophyll, which is contained within a cell organelle called the _____ captures the light from the sun

Answer 12

chloroplast

Question 13

Chemical formula for photosynthesis

Answer 13

CO2 + 6 H2O → C6H12O6 + 6 O2

Carbon dioxide + Water + Light energy → Glucose + Oxygen

Question 14

How many different kinds of life forms or species do scientist believe are on earth

Answer 14

10 million

Question 15

What is the system currently used by taxonomists called and why?

Answer 15

It is called the Linnaean taxonomic system, in honor os Swedish biologists Carlous Linnaeus (1707-1778), one of the founders of the modern system of biological classification

Question 16

Eukaryotes

Answer 16

consist of all organisms with cells that have true nuclei and membrane-bound organelles. Four kingdoms–animals, plants, protists, and fungi fit into this domian

Question 17

Prokaryotes

Answer 17

Prokaryotes have neither nuclei nor organelles with membranes. True bacteria fit in this domain

Question 18

Archaea

Answer 18

Archaea are microorganisms similar to bacteria in form but genetically so vastly different from everything else on the planet that they deserve their own unique branch on the tree of life. Archaea are often found in extreme environments including acidic conditions, boiling hots springs, deep ocean vents or polar ice.

Question 19

Modern taxonomy uses genetic analysis and comparison of physical traits to classify organisms according to a hierarchy of taxonomic ranks. These include

Answer 19

Kingdom
Phylum
Class
Order
Family 
Genus
Species

Question 20

Egg

Answer 20

Eggs are laid by the adult female insect. Females lay a lot of eggs so that at least some o them will survive

Question 21

Larva

Answer 21

Larva hatch from the eggs and bear no resemblance to their adult parents. They only have one job to eat so it can grow quickly. Can grow 100 times their size during this stage. Butterfly and moth larvae are caterpillars. Fly larvae are maggots and beetle larvae are grubs. Eventually, when growth is complete the larva is transformed into a pupa

Question 22

pupa

Answer 22

the pupa stage is usually considered a resting stage, although much activitiy is going on within a sealed chrysalis or cocoon. Special cells that were present in the larva are now growing rapidly and will become the legs, wings, eyes and other parts of the adult insect. After the reorganization is complete, the pupa splits to reveal the mature adult with functional wings. This stage can last a few weeks, a month or even several years.

Question 23

Incomplete Metamorphosis

Answer 23

About 12 percent of all insects go through incomplete metamorphosis. These include stinkbugs, earwigs, crickets, grasshoppers, cockroaches, ants, praying mantis, and dragonflies. Incomplete metamorphosis has only three life cycle stages: egg, nymph, and adult. The nymph looks similar to, but is a smaller version of, the adult. The nymph is also wingless. As nymphs grow, they shed their hard exoskeletons, a process called molting. There is no pupal stage during incomplete metamorphosis.

Question 24

Incomplete metamorphosis has only three life cycle stages name them

Answer 24

egg, nymph, and adult

Question 25

Heredity

Answer 25

Heredity is defined as the transmission of characteristics carried by the genetic code from one generation to the next. Characteristics may be physical, physiological, or psychological as long as they are carried by the genes. Heredity explains why offspring look like their parents and why dogs always give birth to puppies and never guppies or butterflies. Through heredity, living things inherit traits from their parents.

Question 26

Genes

Answer 26

Chromosomes are microscopic, threadlike structures that contain the genes that carry hereditary information from one generation to the next. Each chromosome contains many genes. Different organisms may have different numbers of chromosomes. In sexually reproducing organisms, chromosomes occur in pairs—one chromosome of each pair comes from the mother and one from the father. Humans have 23 pairs of chromosomes. One pair, consisting of two X chromosomes (XX) in females or an X and a Y chromosome (XY) in males determines the gender of the offspring. The other 22 pairs are called somatic chromosomes because their genes produce proteins for building the body rather than determining gender. In eukaryote organisms, chromosomes, and their genes are found in the nucleus, which is surrounded by its own membrane. In bacteria, no nucleus is present and the chromosomes are found in the cytoplasm of the cell.

Question 27

The other 22 pairs are called somatic chromosomes because…

Answer 27

their genes produce proteins for building the body rather than determining gender.

Question 28

Simple food chain example

Answer 28

A simple food chain might look like this: sun → grass → grasshopper → toad → snake → hawk → bacteria of decay

Question 29

Commensalism

Answer 29

In a commensal relationship, members of different species live together, and one member benefits without seriously affecting the other party. As a rule, the animal that benefits is usually the physically smaller of the two. The commensal organism may depend on its host for food, shelter, support, or transportation. The animal that benefits is known as the commensal, or symbiont, while the nonbenefitting species is known as the host. For example, some flatworms live attached to the gills of the horseshoe crab, obtaining bits of food from the horseshoe crab’s meals; the horseshoe crab is apparently unaffected.

Question 30

Mutualism

Answer 30

In mutualism, members of two different species benefit by associating together. For example, many plant species require an animal to visit its flowers for pollination. The animal benefits in this relationship by having a source of food (nectar or pollen), while the plant benefits by having its ovules fertilized.

Question 31

Parasitism

Answer 31

In parasitic relationships, one species receives a benefit from the relationship to the detriment of the other species. For example, there are parasitic fishes, such as the lamprey, that attach themselves to other fishes and suck their body fluids. Similarly, tapeworms may attach to the intestines of host humans in their intestines. They constantly take in nutrients and can eventually cause organ and tissue damage.

Question 32

Quark

Answer 32

At the present time, scientists believe that this is most fundamental particle of matter

Question 33

Total elements, number of which occur naturally on earth

Answer 33

117, 94

Question 34

Compounds

Answer 34

groups of two or more elements that are bonded together through chemical change

Question 35

Iconic

Answer 35

If elements electrons are transferred from one atom to another

Question 36

Covalent

Answer 36

If electrons are shared

Question 37

Law of Conservation of Matter

Answer 37

Atoms are neither gained nor lost during a chemical change. matter can neither be created nor destroyed in a chemical reaction. In a chemical change, however, a new substance is formed, and there may be accompanying clues that a chemical reaction has taken place, such as light, heat, color change, gas production, odor, or sound.

Question 38

Newtons First Law

Answer 38

Newton’s First Law of Motion states that an object at rest will remain at rest and a body moving with a constant speed in a straight line will maintain its motion unless acted upon by an unbalanced external force. An example of force that opposes the motion of a body is friction.

Question 39

Newtons Second Law

Answer 39

Any change in motion involves acceleration, or how much the velocity of an object changes in a certain time. This is where Newton’s Second Law applies; it gives us the relationship between force, mass, and acceleration. Using Newton’s Second Law, force is expressed by the mathematical equation, F=ma or Force=Mass × Acceleration. The greater the mass of the object being accelerated, the greater the amount of force needed to accelerate the object.

Question 40

Newtons Third Law

Answer 40

Newton’s Third Law states that all forces in the universe occur in equal but oppositely directed pairs; for every action, there is an equal and opposite reaction. Rockets and jet planes capitalize on Newton’s Third Law. Each discharge hot gases in one direction (an action force so as to produce thrust (a reaction force). In both rocket and jet engines, chemical energy is changed to the energy of motion.

Question 41

Inclined Plan

Answer 41

An inclined plane is a slanted surface used to raise an object. A ramp is an inclined plane. When an object is moved up an inclined plane, less effort is needed than if you were to lift it straight up, but you must move the object over a greater distance.

Question 42

Wedge

Answer 42

A wedge is an inclined plane which moves. Most wedges (but not all) are combinations of two inclined planes. A knife, axe, razor blade, and teeth are all good examples of wedges. Generally, it can be anything that splits, cuts, or divides another object including air and water.

Question 43

Screw

Answer 43

A screw, like a wedge, is another form of an inclined plane. A screw is an inclined plane wrapped around a cylinder to form a spiral.

Question 44

Lever

Answer 44

A lever has three parts: a fulcrum, an effort arm, and a resistance arm. There are three types, or classes, of levers. In all first class levers, the Fulcrum is between the Effort and Resistance (ex., seesaw). In all second class levers, the Resistance is between Fulcrum and the Effort (ex., wheelbarrow). In all third class levers the Effort is between the Resistance and Fulcrum (ex., baseball bat and tweezers).

Question 45

Pulley

Answer 45

A pulley is a chain, belt or rope wrapped around a wheel. The mechanical advantage of a pulley system is approximately equal to the amount of supporting ropes or strands. A rig on a flagpole or a sailing mast are examples of pulleys.

Question 46

Wheel and axle.

Answer 46

A wheel and axle is a lever that rotates in a circle around a center point, or fulcrum. The larger wheel (or outside) rotates around the smaller wheel (axle). Bicycle wheels, Ferris wheels and gears are all examples of a wheel and axle. Wheels can also have a solid shaft with the center core as the axle such as a screwdriver or drill bit or the log in a log rolling contest.

Question 47

Compound Machines

Answer 47

Compound machines are two or more simple machines working together. A wheelbarrow is an example of a complex machine that uses a lever and a wheel and axle. Machines of all types make work easier by changing the size or direction of an applied force.

Question 48

Electromagnetic (EM) radiation

Answer 48

Visible light or the light energy we see, is the only one small portion of a family of waves called electromagnetic radiation. If you listen to the radio, watch television, have your teeth x-rayed, talk on a cell phone, or use a microwave oven, you are making use of different types of electromagnetic radiation. Electromagnetic waves are generated by accelerating electric charges. For example, if an electric charge oscillates back and forth, it will radiate energy in the form of an electromagnetic wave. The quickness, or frequency at which charges oscillate, determines the type of electromagnetic radiation produced

Question 49

Amplitude

Answer 49

A measure of the distance between a wave’s crest and trough

Question 50

Frequency

Answer 50

The number of oscillations the wave undergoes in a certain amount of time

Question 51

Electromagnetic Spectrum

Answer 51

is defined by frequency and wavelength. Electromagnetic waves occur when a charged object is accelerated or decelerated. They include radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, x-rays, and gamma rays.

Question 52

wavelength in the electromagnetic spectrum

Answer 52

vary in size from very long radio waves the size of buildings, to very short gamma-rays smaller than the size of the nucleus of an atom

Question 53

Wavelengths in electromagnetic spectrum from longest to shortest.

Answer 53

radio waves, microwaves, infrared, visible, ultraviolet, X-rays, and gamma-rays

Question 54

the Law of Reflectance

Answer 54

the angle of incidence equals the angle of reflection. Scattering is merely a reflection from a rough surface. Incoming light waves are reflected at many different angles because the surface is uneven

Question 55

Convex Lens

Answer 55

The most commonly-seen type of lens. A convex lens is a converging lens; it focuses the light passing through it to a point. A convex lens is used to bend light in a magnifying glass so objects appear larger than they really are. A concave lens spreads out light rays that have been refracted through it

Question 56

Concave

Answer 56

A concave lens is used to correct short-sightedness

Question 57

Static Electricity

Answer 57

Static electricity. In order to understand static electricity, it is important to review the basics of atoms. An atom consists of protons, electrons, and neutrons. Protons have a positive charge, electrons are negatively charged, and neutrons have no charge. Because atoms normally have the same number of electrons as protons, the positive and negative charges cancel each other out and, as a result, atoms usually have no charge; they are neutral. Static electricity is the result of an imbalance between negative and positive charges in an object. Normally, the protons and neutrons in the nucleus are held together very tightly. But some of the outer electrons are held very loosely; they can move from one atom to another. If an electron is removed from a neutral atom, the atom is left with more positive particles and acquires a positive charge. If an electron is added to a neutral atom, the atom has more negative particles and acquires a negative charge. The more positive atoms or negative electrons you have, the stronger the attraction for the other. For example, rubbing a shoe against a carpet creates an excess of electrons. When reaching and touching a doorknob a shock, or tiny spark, is felt or seen; excess electrons are released to recreate a balance of electrons and protons in atoms. Lightning is also a result of static electricity

Question 58

Current Electricity

Answer 58

Current electricity comes from a stream of electrons moving through a conductor, such as copper. Some materials allow charges, usually electrons, to flow through the material. These materials are called conductors, and the flow of charge is called current. Some materials are better conductors than others; they offer very little resistance to the flow of electrons. Most metals are very good conductors—copper, silver, gold, aluminum, or steel, for example. However, not all substances are good conductors. Materials that do not conduct electricity well are called insulators. Rubber, plastic, wood, cloth, glass, and dry air are good insulators; they have very high resistance to the flow of electrons.

Question 59

Insulators

Answer 59

Materials that do not conduct electricity well

Question 60

circuit

Answer 60

means circle
Movement of electric charge along a path between areas of high electric potential and low electric potential is the definition of a simple circuit.

Question 61

Magnetism

Answer 61

A magnet is any object that has the ability to attract ferrous objects like iron, steel, nickel, and cobalt. Magnetite, called lodestone for many years, is a naturally occurring iron ore that has this ability. Most permanent magnets we use are manufactured and are a combination or alloy of aluminum, nickel, cobalt, and iron, although none of these metals is naturally magnetic. The magnetic field in a permanent magnet is a result of electron spin. A magnetic field is produced by spinning electrons in an atom. Every atom is essentially a small magnet with a north pole and a south pole. In nonmagnetic materials, electrons spin in random directions, so the magnetic field is not noticeable. In magnets, however, the electrons all spin in the same direction—they are aligned—and create a north pole and a south pole. When a bar magnet is suspended at its center by a string, it will rotate until one end points north. That end is called the north pole of the magnet and the end that points south is called the south pole. In magnets, unlike poles attract, and like poles repel. Either pole, however, can attract iron objects such as pins and paper clips. That is because under the influence of a nearby magnet, each pin or paper clip becomes a temporary magnet, with its poles arranged in a way appropriate to magnetic attraction

Question 62

Magnetite

Answer 62

called lodestone for many years, is a naturally occurring iron ore that has this ability.

Question 63

Magnetic Field

Answer 63

Can be formed not only my a magnetic field, but also by electric current flowing though a wire.

Question 64

Electricity and Magnetism

Answer 64

Electricity and magnetism are closely related The movement of electrons creates a magnetic field, so electric current creates a magnetic field. This magnetic property can be used to make powerful electromagnets. You can make an electromagnet by simply coiling wire around a thin rod made of iron or steel (a nail will work, too). When an electric current moves through the wire, it makes a magnetic field. The strength of the magnetic flow is dependent on the number of times the wire is coiled around the rod, and the value of the current is dependent on the flow through the conductor. The strength of the electromagnet becomes greater as the number of loops of wire around the core is increased

Question 65

Chemical Energy

Answer 65

Energy stored in bonds of atoms and molecules is described as chemical energy. Gasoline and coal contain stored chemical energy.

Question 66

Electrical Energy

Answer 66

Electrical energy is produced by the movement of electrically-charged particles (electrons). The movement of electrons through a conductor, such as a wire, is called current (or circuit) electricity. Lightning is an example of a giant spark of static electricity, or the sudden movement of electrons from a cloud to another surface

Question 67

Heat Energy

Answer 67

Heat energy is created by the random movement of molecules from a warm substance to a cool substance. Temperature, measured in degrees, is an indication of the average kinetic energy of the moving molecules—the speed at which they move. If the molecules in a substance move slowly, the substance has a low temperature. If the molecules move rapidly, the substance has a high temperature. Heat energy is transferred in three ways

Question 68

Conduction

Answer 68

Conduction is the process by which energy is transferred through matter by collisions between particles. It is the transfer of heat energy from atom to atom within a substance. As one molecule is heated, it begins to vibrate. As it does, it passes some of its energy to other molecules around it. Through this process, all the molecules of an object pass energy from one to another, until they are all hot. This is conduction. For example, a metal spoon in a cup of hot soup becomes warmer because the molecular motion of the hot soup molecules is transferred, via collisions, along the length of the spoon, to the molecules in the metal spoon

Question 69

Convection

Answer 69

Convection is the transfer of heat in a gas or liquid by the circulation of currents from one region to another. In convection, the molecules get heated and rise up; the cold molecules sink and get reheated. Then they rise again to continue the cycle. For example, heat leaves a coffee cup as the currents of steam and air rise. During convection, mass is transferred from one location to another

Question 70

Radiation

Answer 70

Radiation is the transfer of energy by electromagnetic waves through space. Sunlight is a form of radiation that is radiated through space to our planet through a vacuum

Question 71

Nuclear Energy

Answer 71

Nuclear energy is stored in the nucleus of an atom—the energy that holds the nucleus together. Energy is released when nuclei are combined or split apart. Einstein showed that this energy is equivalent to mass. Nuclear power plants produce energy by splitting the nuclei of uranium atoms through a process called nuclear fission

Question 72

Moon Phases

Answer 72

The phases, or changes in appearance of the moon, depend on its position relative to the position of the sun. When the moon is between the sun and Earth, the side of the moon facing the Earth is dark. This is called a New Moon. As the moon travels eastward in its orbit, more of its sunlit side becomes visible to Earth and the moon is said to be waxing. As the moon orbits Earth, the side of the moon facing Earth eventually becomes fully lit. This is called a Full Moon phase. As the moon continues to around in its orbit, the lit portion of the moon visible to Earth becomes smaller, so the moon is now said to be waning. As it completes its revolution around Earth, the moon starts the cycle again as a New Moon.

Question 73

The Geosphere

Answer 73

Earth’s geosphere can be divided into three main layers—the crust, mantle, and core. Physical conditions in Earth’s interior vary from layer to layer partly because, as temperature and pressure increase with depth, and the properties of rocks and minerals change

Question 74

Kinetic Energy

Answer 74

Energy of an object in Motion

Question 75

Potential energy

Answer 75

refers to the capacity for doing work