Bio matering chpt.2
A function of cholesterol that does not harm health is its role _____.
as a component in animal cell membrane
__________, a component of plant cell walls, is most abundant organiz compounds found on earth
cellulose
which of these is not a lipid?
RNA (what is? cholesterol, steroids and wax)
DNA has _________ what 4th base?
Thymine (T)
this atom can form up to ___ single covalent bonds
4 There are four electrons in the outermost electron shell.
What is the pH of a neutral solution?
7
According to this research, which of the following people is most likely to test positive for breast cancer?
A woman with elevated phosphoproteins in her blood
Which of these structures stores, modifies, and packages products?
A- The Golgi apparatus modifies, stores, and packages products of the ER.
What would you call the substances that donate protons (H+) to a solution?
Acids- Acids donate H+ ions to a solution. The pH scale is a measure of the relative percentages of H+ and OH- ions in a solution.
in the accompanying image, a nucleotide is indicated by the letter ___squared inside double helix
B
_____ is/are identical in structure to centrioles.
Basal bodies -and centrioles have identical structures.
Choose the letter that indicates the organelle that contains most of a cell's DNA. In an animal cell structure
C- the nucleus contains most of a cells DNA
The structure that regulates the passage of material into and out of this bacterial cell is indicated by the letter _____.
C- the plasma membrane is slectively permeable
The sequence for a strand of DNA is shown below: GCGATTGATAGCCGTAC What is the sequence for its complementary strand?
CGCTAACTATCGGCATG -Each A pairs with T, and each C pairs with G in complementary strands
What name is given to the rigid structure, found outside the plasma membrane, that surrounds and supports the bacterial cell?
Cell wall- rigid supporting structure
The _____ is composed of DNA and protein. (in animal cells)
Chromatin is composed of DNA and protein.
Which of these provides the cell with structural support?
D- Microfilaments are a component of the cytoskeleton.
The DNA-containing region of this bacterial cell is indicated by the letter _____.
D- nucleiod region contains DNA
Which feature is found in both prokaryotic and eukaryotic cells?
DNA- both have genetic material
you can tell this is an ____ nucleotide because you see a
DNA- Nucleotide composed deoxyribose & 2 oxygen atoms in sugars
Which of these is the double membrane that encloses the nucleus?
E- This is the nuclear envelope.
_____ are surface appendages that allow a bacterium to stick to a surface.
Fimbriae
which of the following is an element?
Hydrogen
You discover a new extracellular vesicle similar to microvesicles and exosomes. Which of the following is true?
It is membrane encapsulated and stable.
Which of these are hollow rods that shape and support the cell? (animal cell)
Microtubules - are rods that also play a role in organelle movement
which of these is a source of lactose?
Milk
Which of these organelles carries out cellular respiration?
Mitochodrion -Mitochondria convert the chemical energy of organic molecules to chemical energy in the form of ATP.
Which macromolecule has a sugar-phosphate backbone?
Nucleic acid - has nucleotide; sugar+ phosphate+ nitrogenous base(ATCG)
Which of these organelles produces H2O2 as a by-product? (in animal)
Peroxisomes -produce hydrogen peroxide as a by-product of their metabolic processes.
How do prokaryotic and eukaryotic cells differ?
Prokaryotic cells do not have a nucleus- the DNA in a prokaryotic cell is not contained within a separate membrane-bounded compartment but is found in the cytoplasm of the cell.
Which term best describes the sugar in a sugarwater solution?
Solute
How do the concentrations of H+ and OH- compare to each other in an acidic solution?
The concentration of H+ is higher.
which of these nitrogenous bases found in DNA but not in RNA?
Thymine
In a DNA double helix an adenine of one strand always pairs with an ________of complementary strand and a guanine of one strans always pairs with ______of the complementary strand
Thymine and Cytosine
RNA has what 4th base?
Uracil (U)
What is the solvent in a sports drink that contains water, high fructose corn syrup, sodium chloride, and food coloring?
Water- Water is a solvent that can dissolve the sugars and salts found in sports drinks. See Section 2.1.
RNA has
a nucleotide composed ribose sugars and 3 oxygen atoms
What is metabolism?
all chemical processes that occur in cells (breaks down substances, synthesis, waste)
Which monomer units combine to form proteins?
amino acids
an iconic bond invloves
an attraction between ions of opposite charge
Milk has a pH that is close to 7. Apple juice has a pH of 4. How does the pH level of apple juice compare to the pH of milk?
apple is 1000 times more acidic. ***Each pH unit is 10 times different than the number before or after it. A difference of 3 units would equal a difference of 10 × 10 × 10 = 1000 H+ ions.
atoms with the same # of protons but different electrical charges:
are different ions
What is the name of a molecule composed of one or more sugars?
carbohydrate- major energy and made of sugar subunits
Which element is the basis for the macromolecules found in living things?
carbon
Which feature is found in prokaryotic cells?
cell wall
which of these is a polysaccharide?
cellulose (plant cells store sugars in form of polysaccharide called starch) (major compenent of plant cell walls
Which of the following is a lipid?
cholesterol
what type of bond is joining the 2 hydrogen atoms?
covalent (which is shared electrons)
Which type of chemical bond joins adjacent nucleotides along the length of a strand of DNA?
covalent bonds
What kind of bond is found between the individual atoms of a single water molecule?
covalent bonds that are polar
carbohydrates- glucose + glucose---> maltrose +water....
dehydration synthesis (digestion of starch, in a sprouting seed or in the intestine of an animal, produces maltrose
DNA has what sugar?
deoxyribose sugar
DNA has the apperance of a
double helix (eukaryotic DNA is organized as a double helix)
DNA has how many strands?
double stranded
A pharmaceutical company hopes to improve Tao's test to make it cost efficient by finding an effective way to measure phosphoproteins. Which of the following would be best as this is where phosphoproteins are found?
effectively isolate plasma
True or false: The main function of proteins in a cell is to provide energy for daily activities.
false- Proteins play structural, enzymatic, and transport roles in a cell. Carbohydrates are the main source of energy for daily activities
True or false: Prokaryotes do not have DNA.
false- but not contained in nucleus
A student eats a meal consisting of fruit salad, beef tacos with extra cheese and guacamole, and a glass of 2% milk. Which part of the meal would contain the least amount of fat?
fruit- Fruit salad would contain carbohydrates but little or no fat.
Carbohydrates- _____ is a polyssccharide found in animals
glycogen (especiallyy in liver & muscle and equivalent to plant starch
name for ability of living things to mantain relatively constat internal environment?
homeostasis
The brackets are indicating a(n) _____ bond.
hydrogen bond
What name is given to the bond between water molecules?
hydrogen bonf
How would a nonpolar molecule be described?
hydrophobic- Nonpolar molecules are hydrophobic because they do not easily mix with water.
In salt, what is the nature of the bond between sodium and chlorine?
ionic
Part complete Why is oxygen considered highly electronegative?
it pulls electrons towards itself (attract e-)
Imagine a newly discovered biological molecule that is mostly hydrophobic in its structure. How would this new molecule be classified?
lipid
which feature is present in all known lving things
metabolic reactions
a__________ refers to two or more atoms held by covalent bonds
molecule
Where is a bacterial cell's DNA found?
nucleoid region -Bacteria lack a nucleus; their DNA is found in the nucleoid region.
Ribosomal subunits are manufactured by the _____.
nucleolus
Which monomer units combine to form nucleic acids?
nucleotides
DNA is composed of biulding blocks called
nucleotides units
whats rich in saturated fats?
olive oil (rich in plants oils)
You wish to study dephosphorylation and how it could be used in cancer treatment. Which of the following will you need to use to dephosphorylate phosphoproteins?
phosphatase
The _____ is a selective barrier, regulating the passage of material into and out of the cell.
plasma membrane
The _____ is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell.
plasma membrane- it's selectively permeable
Part A Part complete What type of electric charge do protons carry?
positive
What is the function of a bacterium's capsule?
protection -A bacterium's capsule has a protective role.
which of these are pyrimidines?
pyrimidines are single-ring structures
What does "hydrophobic" mean?
repelled by water
RNA has what sugar?
ribose sugar
_____ are the sites of protein synthesis.
ribosomes
In a bacterium, where are proteins synthesized?
ribosomes -Ribosomes are involved in the manufacture of polypeptides (proteins).
Which of these manufactures cellular membranes by adding membrane proteins and phospholipids to its own membrane?
rough endoplasmic reticulum- As membrane proteins grow from ribosomes on rough ER, the proteins are embedded into the rough ER membrane.
RNA has how many strands?
single stranded
Where is calcium stored?
smooth endoplasmic reticulum- In addition to storing calcium, the smooth ER also plays a role in detoxification and lipid synthesis.
Which monomer units combine to form polysaccharides?
sugars
Which component of amino acids accounts for the differences in their properties?
the side group- They are chemical groups that give AA diff chemical properties
If Tao's theories prove correct, what role do microvesicles and exosomes play in cancer?
they spread cancer
True or false: All carbohydrates contain carbon, hydrogen, and oxygen.
true
True or false: The main function of carbohydrates in a cell is to provide energy for daily activities.
true- Carbohydrates are the main source of energy for daily activities.
Which of the following pairs of molecules can be held together by a hydrogen bond?
two polar molecules
