BIOL test 2 Flashcards
(76 cards)
T or F: The symbol Cl- is the chemical symbol for chlorine after it has lost an electron.
false
Which one of the following always has a positive charge? proton neutron electron atom element
proton
T or F: The symbol Na+ is the chemical symbol for sodium after it has lost an electron.
true
In _______, electron pairs are shared between atoms.
covalent
When the proton number and electron number are unequal, the atom or molecule _____.
is an ion
Which one of the following is NOT a possible function of carbohydrates ?
structural support energy storage energy source catalyze reactions All are carbohydrate functions.
catalyze reactions
In what polysaccharide form do plants store sugar to be available later for energy?
starch
Enzymes are one type of:
protein
Which of the following molecules consists of repeating amino acids units?
protein
The name “double helix” refers to a ______ molecule.
DNA
Lipids
a. have more than twice the calorie content of protein.
b. are structural components of the cell wall.
c. are composed of chains of amino acids.
d. all of the above.
e. a and c are correct.
have more than twice the calorie content of protein
T or F: According to the Cell Theory, DNA is the genetic material in all cells.
False
The Cell Theory states that…
a. cells are the basic unit of life
b. all cells arise from preexisting cells
c. all organisms are composed of cells
d. all of the above
e. only a and c
All of the above
The _____ is a selective barrier, regulating the passage of material into and out of the cell.
plasma membrane
The material which makes up the middle lamella and gives stickiness to fruit jellies is:
pectin
T or F: The cell wall is formed by the nucleus and consists of primary, secondary, and tertiary.
false
An organelle common in plant cells but not found in animal cells is the:
large central vacuole
Which organelle is correctly matched with its function?
a. endoplasmic reticulum; waste disposal
b. ribosome; protein synthesis
c. mitochondrion; transport
d. leucoplast; pigment storage
Ribosome; protein synthesis
Chloroplasts function in:
a. cell division
b. mitosis
c. photosynthesis
d. respiration
photosynthesis
An organelle found in all green plant cells is the:
a. chloroplast
b. chromoplast
c. leucoplast
d. microbody
chloroplast
The concentration of calcium in a cell is 0.3%. The concentration of calcium in the surrounding fluid is 0.1%. How could the cell obtain more calcium? (p. 148)
active transport
T or F:The quantity of water entering a cell in an isotonic solution is equal to the amount of water exiting.
true
T or F: A cell may become turgid when it is placed in pure water or a very weak solution.
true
The region of a chromosome holding the two double strands of replicated DNA together is called _____.
a centromere