Biology - Exam 1 Review

hydrophobic

"water fearing" ; the property, possessed by some compounds, of being unable to form chemical bonds with water molecules

hydrophilic

"water loving" ; the property, possessed by some compounds, of being able to form chemical bonds with water molecules

lysosomes

(animal only) digesting of imported materials and cell's own used material

central vacuole

(plant only) nutrient storage, cell pressure maintenance, pH balance

D) a nonpolar molecule

A molecule that does not have a net electrical charge at one end as opposed to the other is: A) an isotope B) a polar molecule C) a reactant D) a nonpolar molecule E) a solvent

D) a set of principles, supported by evidence, the explains some aspect of the natural world.

A theory, as defined in scientific discourse, is: A) an established fact about the natural world, such as the distance from Earth to the sun B) a long-accepted belief about the natural world C) a concept that is in doubt among most scientists. D) a set of principles, supported by evidence, the explains some aspect of the natural world. E) an initial assumption about how some aspect of nature works.

The phospholipid's phosphate group is hydrophilic The fatty acid chains are hydrophobic

Are phospholipds hydrophilic or hydrophobic?

No - not cellular -- organization stolen from host

Are viruses "alive"?

prokaryotes

Bacteria (cyanobacteria, thermotoga, etc.) and archaea (halophiles and methanosarcina) are examples of what?

B) Carbon cannot be broken down into simpler component substances D) Each carbon atom will always have 6 neutrons

Carbon is an element with an atomic number of 6. Based on this information, which of the following statements could be true? (More than one answer could be true) A) Carbon can be broken down into simpler component substances B) Carbon cannot be broken down into simpler component substances. C) Each carbon atom will always have 6 neutrons. D) Each carbon atom will always have 6 protons. E) Number of protons + number of electrons = 6

eukaryotes

Have a nucleus Much larger in size

prokaryotes

Have no nucleus Can live in extreme environments Single-celled Bacteria

E) are hydrophobic

Janine has dry skin, so she uses body oil every morning. The oil seals in some of the water on her skin, so that it doesn't get dry. This is possible because oils: A) are hydrophilic B) are rare in nature C) have a high specific heat D) are more dense than water E) are hydrophobic

E) Prokaryotic cells

Jerome has strep throat, a bacterial infection. The cause of the infection is: A) the growth of a virus B) the presence of archaea C) eukaryotic cells dividing in his throat D) Organelles that take control of his organs - in this case, his throat E) Prokaryotic cells

matter and energy

Living things require two things. What are they?

E) high specific heat

Near an ocean or other large body of water, air temperatures do not vary as much with the seasons as they do in the middle of the continent. This tendency of water to resist changes in temperature is the result of water's: A) high density B) low density C) being a good solvent D) low specific heat E) high specific heat

B) has a filled outer shell C) has no tendency to form covalent bonds

Neon has an atomic number of 10 and thus has eight electrons in its second energy level. Thus neon (select all that apply): A) has a strong tendency to form covalent bonds B) has a filled outer shell C) has no tendency to form covalent bonds D) is polar E) all of these

A) They can share electrons, but unequally

Oxygen and hydrogen differ in their electronegativity, Thus: A) They can share electrons, but unequally B) sometimes oxygen takes electrons completely away from hydrogen C) They can share electrons equally D) Hydrogen is attracted to oxygen but does not bond with it E) They have the same number of protons

C) acidic

Some plants live in bogs in which the pH is about 2. Thus these plants are able to survive in a(n) ______ external environment. A) basic B) buffered C) acidic D) neutral E) alkaline

Attain and expand human knowledge of the natural world

The aim of science is to what?

Carbon Nitrogen Oxygen Hydrogen

What are the "Big 4" elements in your body?

Carbohydrates Lipids Proteins Nucleic Acids

What are the 4 central macromolecules?

Assimilate energy Respond to environment Homeostasis Reproduce DNA/RNA 1+ cell Evolved Highly organized

What are the defining characteristics of living things? (8 things)

1) Universal solvent 2) Cohesion 3) High heat capacity 4) Low density as a solid

What are the four properties of water?

the nucleus

What compensates for the majority of the mass of an atom?

a polypeptide chain

What does the linkage of several amino acids produce?

glucose

What is a example of a (common) form of monosaccharides?

Matter = cycled Energy = not cycled

What is the difference between matter and energy?

atom

What is the fundamental unit of matter?

it serves as the primary form of carbohydrate storage in animals

What is the main purpose of glycogen?

It gives shape and strength to the structure of the organism

What is the main purpose/function of chitin in living organisms (more specifically, arthropods)?

Oxygen = 65% Carbon = 19% Hydrogen = 10% Nitrogen = 3%

What is the make-up of the "Big 4" in percentages?

Sunlight > Primary Producers > Primary Consumers > Secondary Consumers > Tertiary Consumers

What is the order of the energy chain? (consumers, producers, etc.)

Covalent is the strongest Hydrogen is the weakest

What is the strongest type of bond? What is the weakest?

Chitin

What makes up a large portion of the outer "skin" or cuticle of arthropods?

Cellulose

What provides structural support for plants and other organisms?

Glycogen

What serves as a form of carbohydrate storage in animals?

starch

What serves as a form of carbohydrate storage in many plants?

Central vacuole Cell wall Chloroplasts

What three cell organelles/structure are only found in plant cells?

C) A hypothesis is a tentative explanation that can be test, usually through experimentation.

Which of the following statements best describes the nature of a scientific hypothesis? A) A hypothesis is an idea that is widely accepted as a description of objective reality by a majority of scientists B) A hypothesis must stand alone and not be based on prior knowledge. C) A hypothesis is a tentative explanation that can be test, usually through experimentation. D) A hypothesis must deal with an aspect of the natural world never dealt with before. E) A hypothesis, when accepted, becomes scientific law.

Because of the Hydrogen-bonds -- it takes a lot of energy to break the hydrogen bonds

Why does water have a high-heat capacity?

solvent, solute

You add sugar to your coffee, and the sugar dissolves. Thus the coffee is the ______ and the sugar is the _____.

phospholipid

a charged lipid molecule composed of two fatty acids, glycerol and a phosphate group.

hydrogen bond

a chemical bond that links an already covalently bonded hydrogen atom with a second, relatively electronegative atom

steroids

a class of lipids that have, as a central element in their structure, four carbon rings

hydrocarbon

a compound made of hydrogen and carbon; these compounds are nonpolar covalent molecules and are therefore, not easily dissolved in water

saturated fatty acid

a fatty acid with no double bonds between the carbon atoms of its hydrocarbon chain

monounsaturated fatty acid

a fatty acid with one double bond between carbon atoms

polyunsaturated fatty acid

a fatty acid with two or more double bonds between carbon atoms

polymer

a large molecule made up of many similar or identical sub-units, called monomers

ionic bond

a linkage in which two or more ions are bonded to each other by virtue of their opposite charge

triglyceride

a lipid molecule formed from three fatty acids bonded to glycerol

lipid

a member of a class of biological molecules whose defining characteristics is their relative insolubility in water; examples are triglycerides, cholesterol, steroids, and phospholipids

plasma membrane

a membrane forming the outer boundary of many cells, composed of a phospholipid bilayer interspersed with proteins and cholesterol molecules and coated, on its exterior face, with short carbohydrate chains associated with proteins and lipids

fatty acid

a molecule that is found in many lipids that is composed of a hydrocarbon chain bonded to a carboxyl group

phosphate atom

a phosphorus atom surrounded by four oxygen atoms

polysaccharide

a polymer of carbohydrates, composed of many monosaccharides; examples include starch, glycogen, cellulose, and chitin

cellulose

a structural, complex carbohydrate produced by plants and other organisms

element

a substance that can't be reduced to any simpler set of constituent substances through chemical means

polar-covalent bond

a type of bond in which electrons are shared unequally between atoms , so that one end of the molecule has a slight negative charge and the other end a slight positive charge

covalent bond

a type of chemical bond in which two atoms are linked through a sharing of electrons

passive transport

any movement of molecules or ions across a cell membrane that does not require the expenditure of energy

active transport

any movement of molecules or ions across a cell membrane that requires the expenditure of energy

base

any substance that accepts hydrogen ions in solution; it has a number higher than 7 on the pH scale

acid

any substance that yields hydrogen ions in solution; it has a number lower than 7 on the pH scale

starch

complex carbohydrate found in plants; its most common forms are potatoes, rice, corn, and carrots

chitin

complex carbohydrate that forms the external skeleton of arthropods (all inseacts, spiders and crustaceans

simple diffusion

diffusion through a cell membrane that does not require a special protein channel

ATP

high-energy molecule found in every cell; its job is to store and supply the cell with needed energy

cell walls

limit water uptake; maintain cell membrane shape, protect form outside influences

smooth endoplasmic reticulum

lipid synthesis, storage; detoxification of harmful substances

cytoskeleton

maintains cell shape, facilitates cell movement and movement of materials within cell

density

measure of space between molecules

null hypothesis

no relationship between two variables

carbohydrates

organic molecules that always contain carbon, oxygen, and hydrogen; in some instances, contain nothing but carbon, oxygen and hydrogen; usually have twice as many hydrogen atoms than oxygen atoms

noble gases

outer shell valence electron shell is "full" (stable) giving them little tendency to bond with other atoms

chloroplasts

photosynthesis

buffering systems

physiological systems that function to keep pH within normal limits

golgi complex

processing, sorting proteins

rough endoplasmic reticulum

protein processing

cytosol

protein-rich fluid in which organelles and cytoskeleton are immersed

alternative hypothesis

relationship between the variables; what you predict

nucleus

site of most of the cell's DNA

ribosomes

sites of protein synthesis

cholesterol

steroid molecule that forms part of the outer membrane of all animal cells and that acts as a precursor for many other steroids

nucleolus

synthesis of ribosomal RNA

high heat capacity

takes a lot of energy to change phase (liquid, solid, gas)

monosaccharides

the building blocks of carbohydrates; these are the monomers of carbohydrates; also known as simple sugars

phagocytosis

the movement of large materials into a cell by means of wrapping extensions of the plasma membrane around the materials and fusing the extensions together

exocytosis

the movement of materials out of the cell through a fusion of a transport vesicle with the plasma membrane

pinocytosis

the movement of relatively large materials into a cell by means of the creation of transport vesicles that are produced through an invagination of the plasma membrane

endocytosis

the movement of relatively large materials into the cell by infolding of the plasma membrane

osmosis

the net movement of water across a semi-permeable membrane, from an area of lower concentration to an area of higher concentration

facilitated diffusion

the passage of materials through the plasma membrane that is aided by a transport protein

cohesion

the tendency of water molecules to stick together

mitochondria

transform energy from food

vesicles

transport of proteins and other cellular materials

independent variable

what you change or manipulate

dependent variable

what you measure (in an experiment)