1.Andrea is viewing a plant cell with a compound microscope. She notices a large, "empty" structure. When Andrea adds salt water
, the structure decreases in size. Andrea is observing _______________. Select one:
a. a lysosome
b. a nucleus
c. a central vacuole
d. a peroxisome
2.A prokaryotic cell's genetic material differs from eukaryotic cells. Prokaryotes have ___________________.
Select one:
a. One circular DNA molecule
b. Half as many chromosomes as a human cell
c. One large, X shaped chromosomes
d. One small, Y shaped chromosome
3.A cell with no nuclear membrane and few (if any) membrane-bound organelles is called a __________ .
Select one:
a. eukaryote
b. prokaryote
c. karyotic
d. phlembiotic
4.Ribosomes are crucial proteins in cells because:
Select one:
a. they are responsible for providing protection from invaders.
b. they provide the structural components of all cells.
c. they only operate in eukaryotic cells.
d. they are the sites for protein synthesis.
5.When comparing a sample of plant cells and a sample of animal cells under a compound microscope, a student notices that all of the plant cells are the same shape, whereas the animal cells have variable shapes. What explains this difference?
Select one:
a. The plant cells contain a rigid cell membrane.
b. The animals cells are dead, and have shriveled.
c. The animal cells lack cell walls.
d. The animal cell lacks a central vacuole.
6.Which of the following true statements best supports the endosymbiotic theory?
Select one:
a. All mitochondria have circular DNA.
b. All eukaryotic cells have ribosomes.
c. All eukaryotic cells have DNA.
d. All mitochondria function as powerhouses to the cell.
7.Cells have lysosomes because _______.
Select one:
a. without them, the enzymes they contain would diffuse out of the cell
b. without them, the cell organelles would be hydrolyzed
c. without them, cells would not be able to capture light energy
d. without them, cells would not be able to perform photosynthesis
8.The theory that posits that membrane-bound organelles in eukaryote cells originated as endosymbiotic (living within) prokaryote cells in a primitive eukaryote ancestor cell is called the ________.
Select one:
a. membrane theory
b. prokaryotic theory
c. endosymbiotic theory
d. mitochondrian theory
In Secondary structures; the irregular loops seems to be positioned on the outside of folded proteins while the Alpha and beta sheets is categorically positioned at the centre or interior of the protein.
The loops are positioned on the outside of folded proteins in order for the peptide bonds to be open to form H bonds with water.
