Bio Quiz Questions and Review for Exam 2

The proteins in biological organisms include 20 different kinds of amino acids. What is the minimum number of different types of tRNA molecules that must exist in the cell? How many codons exist for the 20 amino acids?

-At least 20 amino acids -61 codons

1 amino acid is represented by:

1 codon

A particular protein is 5 amino acids long. How many nucleotides code for it?

15 (5x3=15)

The number of nucleotide bases "read" together on the mRNA is designate each amino acid is _____; this unit is called a ______.

3.....codon

In a strand of DNA composed of 15% cytosine, what amount of thymine would be found?

35%

What is a gene?

A sequence of bases in segment of DNA

A nucleotide would not include the ____

Amino acid

A protein is a polymer of

Amino acids

Polypeptides are composed of _____.

Amino acids

Proteins are broken down into ____ while starch is broken down into _____

Amino acids; sugar molecule (or glucose)

____ allows water into and out of the cell.

Aquaporin

The tRNA anticodon, GAC is complementary to the mRNA codon with the sequence _____.

CUG

Where do polysaccharides exists?

Carbohydrates

____ molecules diffuse readily across the membrane.

Carbon dioxide

Cytoskeleton helps in ____

Cell movement, cell support, shape

Where is cellulose located in the plant cell?

Cell wall

What are examples of polysaccharides?

Cellulose, starch, and glycogen

All of the following are proteins except -Hemoglobin -Enzyme -Insulin -Cholesterol -Antibody

Cholesterol

If it is too cold, then the ____ keeps the tail of the phospholipids from getting to close.

Cholesterol

In DNA, how is one nucleotide monomer linked to the next?

Covalent bonds between the sugar of one nucleotide and the phosphate of the next.

Which macromolecule contains an organism's genetic information?

DNA

What are examples of Nucleic acids?

DNA and RNA

Sucrose (table sugar) and lactose (the sugar found in milk) are examples of

Disaccharides

Facilitated diffusion ____ requires energy and uses the help of _____.

Does not, transport protein

What examples of proteins?

Enzyme and amino acids

True or False: Lipid soluble molecules such as alcohol cannot diffuse through the plasma membrane.

False

True or False: The plasma membrane is said to be freely permeable because of the chemical proteins.

False

Which of the following foods is not a significant source of complex carbohydrates? -Oatmeal -All of the listed -Pasta -Fresh fruit -Rice

Fresh fruit

What are the other simple sugars?

Fructose and galatose

A particular ____ carry the information for making a specific polypeptide, but ____ can be used to make any polypeptide.

Gene and mRNA.....a ribosome and tRNA

What is different in the DNA for everyone?

Gene expression

The full set of an individual organism's DNA is called its:

Genome

What are examples of simple sugars/monosaccharides?

Glucose, fructose, galactose

When humans have extra glucose where do they store it as?

Glycogen

What is the shape of unsaturated fats?

Have lots of kinks in the hydrocarbon tails because there is more double bonds The tails cannot be packed together tightly

What is an example of a protein that goes through the quaternary structure?

Hemoglobin.

All of the following are lipids except -Fats -Triglycerides -Steroids -Insulin -Cholesterol

Insulin

____ helps to transport hydrophilic substances to the interior of the cell.

Integral memberane protein

What does "genetic code is universal" mean?

It is shared by all living things.

What are examples of disaccharides?

Lactose and sucrose

The ____ part of the cell membrane functions as a barrier while the ____ does most of the transport.

Lipids and Proteins

What is the role of phospholipid?

Main structural component

Smooth ER plays a critical role in ____

Makes lipids and inactivation of some drugs in liver cells

A person's unique DNA is carried in _____

Muscle cells, hair, salivia

Which one of the following describes a nucleotide most completely?

Nitrogen base, a sugar, and a phosphate group

Is the cell membrane static (stiff)?

No

Is glucose a macromolecule?

No it is a simple sugar ( or monosaccharide).

One gene ->

One polypeptide

Breakdown of ____ part of cell membrane leads to break up of the cell itself.

Phospholipid

If a cell has a cell wall, then it can be identified as a ____

Plant cell or bacterial cell (in bacteria antibodies target cell wall)

Which part of the cell membrane helps in cell-cell signaling?

Proteins

What is the grey matter in the transcription and translation matching?

RNA Polymerase

The most common purpose of proteins is to serve as

Raw material for growth

What is polypeptide?

Sequence of amino acids in a polypeptide chain

In general, which of the following will diffuse across a lipid bilayer most rapidly.

Small hydrophobic molecule

The lipid bilayer is not permeable to ____

Sodium ions

All of the following are carbohydrates except -Cellulose -Starch -Glycogen -Spider's silk -Chitin

Spider's silk

What is the role of cholesterol?

Stabilizes the membranes

Which of the following about starch is incorrect?

Starch tastes sweet because it is made from glucose

What are some complex carbohydrates?

Starch, glycogen, cellulose, chitin.

Which step is just transcription?

Step 1

What does DNA do?

Stores the genetic information (to make proteins)

What is the shape of saturated fats?

Straight hydrocarbon tails and molecules can be packed together tightly

One strand of a DNA molecule has the base sequence ATAGGT. The complementary base sequence on the other strand of DNA will be ____.

TATCCA

At which level is the protein functional?

Tertiary

What happens in the tertiary structure of a protein?

The 3D shape formed by multiple twists and bends in the polypeptide chain.

What happens in the primary structure of a protein?

The sequence of amino acids

Proteins differ from one another because ____

The sequence of amino acids differs

What is starch?

The storage form of energy for plants.

What happens in the secondary structure of a protein?

The twists or pleated folds formed by hydrogen bonds between amino acids.

If protein production were an assembly line, a ribosome would be ____.

The worker who puts all of the pieces together

What is codons?

Three nitrogen bases/nucleotides.

In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) ____ of the complementary strand.

Thymine.....cytosine

What are the role of transmembrane proteins?

Transport (materials in and out of the cell)

What are examples of lipids?

Triglyceride, fatty acid, testosterone, cholesterol, steroid, phospholipid, estrogen

True or False: ALL proteins undergo the structural formation.

True

True or False: If stored properly DNA can store longer than computer devices.

True

True or False: Starch is just in plants.

True

True or False: The more the amount of lipids in a molecule the easier it is for that molecule to pass through a plasma membrane (cell membrane).

True

True or False: An enzyme that breaks down protein will not break down starch.

True, we need a different enzyme to break down starch (enzyme is a protein)

What happens in the quaternary structure?

Two or more polypeptide chains bond together created multiple polypeptides. ONLY SOME PROTEINS GO THROUGH THIS.

When messenger RNA (mRNA) is being made, the RNA base ___ always pairs with the base ___ in DNA.

U....A

Which type of fat is better for our health?

Unsaturated has less calories so better for our health.

During transcription, at the point where DNA strand being copied has an adenine, a(n) ____ is added to the _____.

Uracil; mRNA

Who is generally credited with discovering that the DNA molecule is constructed as a double helix?

Watson and Crick

Does bacteria have ribosomes?

Yes. It does not make organelles though.

The final product of gene expression is _____

a protein

The flow of information in a cell proceeds ____.

from DNA to RNA to protein

The two sugar-phosphate strands of a DNA molecule are joined to each other through ____.

hydrogen bonds between nucleotide bases

Monomers, for the synthesis of DNA are called

nucleotides

There are different ____ molecules for each of the 20 different amino acids that are used in building proteins.

tRNA