Exams Biology

True or false a community is composed of different populations of animals and plants.

true

True or false all tissues are composed of cells

true

what are molecules made up of?

atoms

A community of organisms interacting with their physical environment is?

ecosystem

true or false vertical evolution is the only mechanism of evolution on earth

false

The grouping or classification of species is termed?

taxonomy

The human species is called “Homo sapiens”. The first word refers to which taxonomical grouping?

genus

An explanation for a biological process that is sustained by a large body of evidence is called a

theory

A reseacher tests the hypothesis that large, daily doses of vitamin C helps protect against catching a common cold. What would be the best experimental and control group to test this hypothesis?

Experimental: takes a large daily dose of vitamin C

Control: takes the sugar pil

The atomic number of an atom is

the number of protons

When one atom loses an electron to another atom, it results in the formation of

ionic bond

what type of bonds form from unequal sharing of electrons?

polar covalent bonds

Amphipathic molecules

posses both hydrophobic and hydrophilic properties

Orange juice has a pH of 4, it is considered

acidic

How many covalent bonds can carbon form?

4

What has an identical molecular formula but different structures and characteristics isomers, enantiomers, or stereoisomers?

all

ture or false Macromolecules such as proteins and carbohydrates are produced from monomers through dehydration reactions

true

A disaccharide consists of two molecules, what type of bond links the two?

glycosidic

Fats and fatty acids

are insoluble in water

true or false the sole function of carbohydrates is to serve as energy stores

false

true of false saturated fats are composed of fatty acids with several double-bonded carbons

false

When placed in an aqueous solution, amphipathic molecules will orient themselves with

hydrophilic hydrocarbon chains in the middle and hydrophilic head groups facing the water

true or false the primary structure of a protein ultimately determines its three-dimensional structure

true

the macromolecule that can accomplish the widest range of biological functions are

proteins

cell theory or cell doctrine is based on some basic principles. what is it

All living organisms are composed of one or more cells, cells are the smallest units of life, and new cells come only from pre-existing cells by cell division

To observe the three-dimensional structure of a cells the best type of microscopy would be

scanning electron microscopy

Eukaryotes differ from prokaryotes in that prokaryotes

lack internal compartmentalization

The structure that easily distinguishes a plant cell from an animal cell is

chloroplast

Plasma membranes are a feature of 

all cells

The organelle responsible for the biosynthesis of proteins thaat are destined for secretion by the cell is the

endoplasmic reticulum

The golgi apparatus functions to

modify, sort, and package proteins

What is the main function of the nucleus?

stores genetic information

Which of the following organelles are most likely to be able to divide and reproduce much like a cell does?

both mitochondria and chloroplasts

How many valence electrons does a chlorine have with an atomic number equal to 17?

7

What is the appropriate order of the stages of investigating wheter maple trees drop their leaves in the autumn because of colder days?

1. maple trees are grown in two greenhouses where the only variable is temperatures (15°C vs 10°C)

2. the hypothesis is rejected

3. there is no statistical difference in the number of leaves dropped at 10°C as compared to 15°C

4. the observation is that maple trees drop their leavs in autumn

5. the hypothesis is that maple trees drop their leaves because of colder temperatures

4,5,1,3,2

Whats the monomer of proteins?

amino acids

Whats the monomer of nucleic acids

nucleotide

whats the monomer of carbohydrates?

monosaccarides

What are the same three components for each of the 20 amino acids?

Amino group, carboxyl group, and hydrogen atom

In each 20 amino acids what are the group that is different on each?

R group

List two differences between DNA and RNA

DNA: double stranded, G, A, T, C

RNA: single stranded, G, A, U, C

What is contrast?

distinguish between light from dark

What is resolution?

clarity

What is magnification?

the size of the object under a microscope compared to its actual siz

Cellular membranes are: 

a. Semifluid

b.Solely composed of lipids

c.Composed of a single layer of amphipathic molecules

d. found only in eukaryotes

semi-fluid

What is the major lipid found in membranes?

phospholipids

What process is required for phospholipids to flip-flip across the lipid bilayer?

both energy and an enzyme flippase

which membrane component is important for allowing large, uncharged molecules to pass through the membrane?

Transmembrane proteins

Which molecule passes through a lipid bilayer the most readily?

carbon dioxide 

Which binds two r more ions or molecules and transports them in opposite directions across a membrane?

antiporter

The process that most involved the selective uptake of a specific cargo molecule into the cell through receptor binding and aggregation is

receptor-mediated endocytosis

true or false Ion gradients across the membrane drive numerous cellular functions

false

water held behind a dam would best reflect

potential energy

An autotroph captures energy from other sources and does not actually produce energy because

energy cannot be created or destroyed

The amount of available energy that can be used to do work is called

free energy

if an enzyme catalyzes the reactions A + B→ C then, 

the enzyme undergoes a conformational change when bound to A and BH

How does an enzyme work to catalyze a reaction?

it lowers the activation energy of a reaction

If you liver produces 90% of the cholesterol found in your body. When cholesterol levels get to high, the first enzyme in the pathway of cholesterol synthesis is inhibited. This is an example of

positive feedbackYo

You measure the amount of enzyme activity in the presence of compound X and notice that enzyme activity decrease. you note that as you add more substrate the amount of enzyme activity increases. this indicates that the compound X is 

a competitive inhibitor

true of false Enzymes are consumed in chemical reactions and must therefore be replenished

false

True of False: temperature, pH and ionic concentrations each play an important role in the proper function of enzymes

true

The equation C6H12O6 + 6O2 → 6CO2 + 6H2O (ATP + heat) is what process

cellular respiration

Which stage of cellular respiration will occur with or without oxygen

glycolysis

Where does glycolysis take place

cytosolH

How many ATP are needed to start glycolysis

2

Cellular respiration produces the most energy in the frm os ATP from which step?

oxidative phosphorylation

What does yeast produce during fermentation?

ethanol

true or falseThe electron transport chain consists of a series of redox reaction in which electrons are transferred to oxygen as the final electron acceptor

true

What is considered electron carrierws in cellular respiration

NADH and FADH2

In the structure of ATP synthase, where do the H+ ions cross the mitochondrial membrane?

between the transmembrane a and c subunits

The source of energy that directly drives the synthesis of ATP during oxidative phosphorylation is

H+ electrochemical gradient

The process which cells can detect and respond to signal in their extracellular environment is

cell communication

When a cell releases a growth factor that binds to receptors on neighboring cells causing them to proliferate is an example of

paracrine signaling

when a cell makes a cell membrane bound growth factor that binds to receptors on neighboring cells causing them to proliferate this is an example of

contact-dependent signaling

Hormones are released from one cell and act on other cells in distant organs is an example of

endocrine signaling

true of false apoptosis is used in humans in order to eliminate cells infected by viruses cells hat are worn out and those that have potential to cause cancer`

true

What factors effect fluidity of phospholipid membrane?

temperature, number of double bonds, length of tails

Simple diffusion

high to low concentration, passive transport

Facilitated diffusion

high to lower concentration, transport protein

Active diffusion

low to high concentration, energy and transport protein

Exergonic reaction

release energy

endergonic reactions

aborbs energy

Catabolic reaction

breaking down

anabolic

synthesizing

What are the products of glycolysis?

pyruvate, 2ATP, NADH

What are the products of breaking down pyruvate?

Acetyl CoA, CO2, and NADH

what are the products of the citric acid cycle?

6NADH, 2 ATP, 2 FADH, 4CO2

what are the products of oxidative phosphorylation

ATP

What are the three stages of responding to a signal?

Receptor activation
signal transduction
cellular response