cell biology final

Which is true of all proteins?

• they have ligands

• thay have substrates

• they have quaternary structure

• all of the above

• none of the above

they have ligands

the lenses in an electron microscope are actually ___

-concave glass

-convex glass

-heavy metal calipers

-magnets

-none of the above

magnets

which of the following types of bonds act in protein folding?

• electrostatic attractions

• hydrogen bonds

• hydrophobic forces

• van der waals interactions

• all of the above

-all of the above

how many valence electrons in carbon

4

which fatty acid type contains NO double bonds?

• omega-3

• polyunsaturated

• saturated

• unsaturated

• all of the above

saturated

what is the carbohydrate in DNA and how many carbons are in it?

2-deoxyribose, 5 carbons

There are ___ common amino acids

20

which of the following chemical groups is not present in the compound in the figure

carboxylic acid

The majority of amino acids have side chains that are ___

• acidic

• basic

• nonpolar

• polar

nonpolar

A derivation of the nucleotide adenine forms the energy molecule ___

Adenosine Triphosphate (ATP)

In a polar covalent bond consisting of hydrogen and oxygen, the ____

Oxygen has a partial negative charge because it is more electronegative than hydrogen

Who showed in the laboratory that spontaneous formation of organic compounds that could form the macromolecules of life could occur in conditions found on primitive earth?

Stanley miller

What living things are the universal building blocks of life?

Cells

Name two basic amino acids

lysine, arginine

name the purine nucleotides

adenine, guanine

how many double bonds are in docosahexaenoic (DHA)

6

Which of the following is a part of all amino acids?

amino group

Name two of the uncharged polar amino acids

Serine, Threonine

The percentage of water in cells ranges from ____ percent

70-96

What would the resolution of a microscope using a light source with a wavelength of 400nm and a numerical aperture of 1 be?

244

Which of the following chemical bonds is due to the random, ever-changing accumulation of electrons in one part of a molecule?

Van der Waals interactions

The cell theory was proposed by

Schleiden and Schwann

Which amino acid is incompatible with the formation of alpha helices?

Proline

Which of the following atoms is most likely to form an anion in a dissociated ionic bond?

Fluorine

Name the four macromolecules of life

proteins, lipids, carbohydrates, DNA

Which of the following is/are present in cells?

All of the above

Sucrose is a disaccharide made of ____

Fructose and glucose

Scientists estimate that prokaryotes were firs found on earth approximately ____ billion years ago

3.5

A monosaccharide with 4 carbons will have ___ oxygens and ___ hydrogens

4 and 8

Which of the following elements make up %96 of all living matter?

Carbon, Hydrogen, Nitrogen, Oxygen

Which of the following is correct about alpha helices?

They are stabilized by hydrogen bonding

Seeing things clearly using a microscope depends on all of the following except ____

Microscope working distance

An electron microscope would be needed to view which of the following?

Ribosomes

How many nanometers are in 1.78 centimeters?

17800000

The earliest light microscopes were noted in the historical records in the ___

1600s

Beta-sheets in which amino (N)-terminal of the beta-strands are aligned are described as ___

parallel

At least some of the illumination source passes through specimens in all of the following types of microscopes except?

Scanning electron

The amino acid sequence of a polypeptide is its ___ structure

primary

Which of the following chemical bonds is strongest in cells?

covalent

When was the cell theory proposed?

1839

Which type of microscopy requires coating the specimen with heavy metal?

scanning electron

A cell with endoplasmic reticulum most likely belongs to the domain ___

eukaryotes

Two microscopes with the same lenses are using different light sources. Microscope A is using visible light. Microscope B is using ultraviolet light that has a wavelength of 350nm. Which of the following is true?

The resolution of microscope B is better than microscope A

Which of the following polysaccharides is made by humans?

Glycogen

The simplest amino acid is ___ and its R group is ___

Glycine, a hydrogen atom

Name 4 things that all living things do

reproduce, breathe, consume, have homestasis

If the pH of cells the normal range of approximately 7.2, the ___ group in amino acids can donate a hydrogen to lower the pH

Carboxyl group

Which of the molecules below demonstrates the ability of chains of carbons to form ring structures?

All of the above

Which of the following polymers are created by dehydration or condensation reaction?

all of the above

Which of the following movements is done by phospholipids in cellular membranes?

All of the above

Catalase is an oxidative enzyme that can be found in ____.

Peroxisomes

Which of the following is correct?

None of the above

Which of the listed organelles has two phospholipid bilayers? (indicate all that apply)

Mitochondria

Nucleus

A/an ___ is a segment of DNA that directs the production of a particular polypeptide or functional RNA molecule.

Gene

How many hydron bonds are between guanine and its correct base-pairing partner in DNA?

3

How many 1. chromosomes and 2. nucleotide pairs are in the human genome in somatic cells?

1. 46

2. 6.2 x 10^9

Proteins make up ___ of the mass of most plasma membranes.

50%

Serial endosymbiosis suggests that ____.

Mitochondria formed because aerobic bacteria united with pre-eukaryotic cells

In the pictured situation, the solutes are the dots.  Which side is the hypertonic solution?

B

The most widely used and abundant activated carrier is ____.

ATP

Gradient-driven antiports do which of the following?

Use the diffusion of one substance into the cell to provide energy for moving a second substance out of the cell

Phospholipids most frequently have fatty acid tails with _____ carbon atoms.

18 to 20

What determines if a ribosome will attach to the endoplasmic reticulum by interacting with proteins in the ER membrane?

Polypeptide

Which of the following is involved in condensing the interphase chormosomes (indicate all that apply)

Cohesins

Condensins

Histone core 

Histone H1

In resting cells, is the charge on the intracellular side of the membrane more negative or more positive?   Name two substances that contribute to this charge difference across the membrane.

More negative, potassium and sodium

Which of the following is NOT a part of the endomembrane system?

Mitochondria

Which of the listed organelles is/are where proteins are assembled, modified, and sent to other destinationsl? (indicate all that apply)

Golgi apparatus

Who produced the x-ray diffraction data on the structure of DNA?

Rosalind Franklin

Protein B has a lipid extension that interacts with fatty acid tails in the cell membrane.  Is protein B an integral or peripheral membrane proteins?

Integral

Large food molecules are brought into cells in ___, which then fuse with ___ to digest the food.

food vacuoles, lyosomes

Who used a phage virus to definitively determine that DNA is the genetic material?

Alfred Hershey, Martha Chase

Which of the following people were involved in determining that DNA is the genetic material? (indicate all that apply)

Oswald Avery

Who in the 1920s used bacteria to provide evidence that there was a "transforming principle."?

Fred Griffith

Name the three parts of a DNA nucleotide.

Phosphate group, nitrogenous base, deoxyribose

Which of the following chemical interactions is most important in formation of the phospholipid bilayer of around cells?

Hydrophobic forces

In nucleosomes, how many nucleotides pairs wrap around the histone core?

147

Regions of DNA where transcription is occurring would most likely be found in _____.

Active euchromatin

Cristae are formed by the ___.

Inner mitochondrial membrane

___ transfers phospolipids randomly from the cytosolic to the lumen side of its phospoipid bilayer and is found in the ____.

Scramblase… smooth er

Histone H1 ____.

Shortens the linker regions between nucleosomes

Which of the following is correct about transmembrane proteins that form channels for hydrophilic substances to pass? 

None of the above

Which of the following statements about the plasma membrane of cells is correct?

None of the above

Proteins that form channels for the osmosis of water in some cells are called ___. 

aquaporins

Why is the movement of sodium ions into human cells more powerful than the movement of potassium ions out of the cells? (indicate all that apply)

Sodium is moving with its voltage gradient toward a negative environment

At normal body temperatures, cholesterol makes cells membranes _____.

Less fluid

Part of the mitotic spindle attaches at the ____ of chromosomes.

Centromeres

Describe what happens at axon terminals of neurons across the synaptic cleft to transmit an electrical signal from one neuron to the next.

It triggers a chemical process to transfer the signal

In the Golgi apparatus, proteins from the endoplasmic reticulum enter the ____.

Cis cesterna

Which of the following is/are used in active transport?

Calcium pump

Which of the listed organelles makes proteins that are secreted from the cell? (indicate all that apply)

Rough endoplasmic reticulum

Who authored the seminal 1953 Nature paper on the structure of DNA?

Francis Crick, James Watson

Who proposed the fluid-mosaic model of the plasma membrane?

Singer and Nicolson

Photosynthesis occurs in which of the listed organelles? (indicate all that apply)

Chloroplasts

Which of the following correctly describes DNA?

One turn of the DNA helix is about 3.4 nm

A saline solution has a concentration of 5mM.  Is it hypotonic, hypertonic, or isotonic?

Cannot be determined

Which of the following occurs during the depolarization stage of an action potential?

Sodium ions enter the cell

Organisms in which of the following domains typically have linear DNA?

Eukaryotes

Very condensed chromatin can be found in all of the following, EXCEPT ____.

Euchromatin

What happens to the volume to surface area ratio in eukaryotes compared to prokaryotes?

Increases

Histone-modifying enzymes add ____ to histones.

all of the above