Some hormones enter cells via __________.
C) receptor-mediated endocytosis
D) primary active transport
What moves cell organelles from one location to another inside a cell?
B) Motor Proteins
D) Intermediate Filaments
Which vesicular transport process occurs primarily in some white blood cells and macrophages?
C) intracellular vesicular trafficking
Which of the following describes the plasma membrane?
A) a double layer of protein enclosing the plasma
B) a membrane composed of tiny shelves or cristae
C) a phospholipid bilayer surrounding the cell
D) a single-layered membrane that surrounds the nucleus of the cell
Crenation (shrinking) is likely to occur in blood cells immersed in ______.
A) an isotonic solution
B) blood plasma
C) a hypotonic solution
D) a hypertonic solution
Which of the following would not be a constituent of a plasma membrane?
A) messenger RNA
Once solid material is phagocytized and taken into a vacuole, which of the following statements best describes what happens?
A) the vacuole remains seperated from the cytoplasm and the solid material persist unchanged
B) A lysosome combines with the vacuole and digest the enclosed solid material
C) the phagocytized material is stored until further breakdown occurs
D) a ribosome enters the vacuole and uses the amino acids in the "invader" to form new protein
Which of these is an inclusion, not an organelle?
The RNA responsible from bringing the amino acids to the ribosome for protein formation is ________.
A) is the formation of sex cells
B) is always a part of the cell cycle
C) creates diversity in genetic potential
D) is division of the nucleus
which of the following is a function of a plasma membrane protein?
A) forms a lipid bilayer
B) circulating antibody
C) molecular transport through the membrane
D) oxygen transport
A gene can best be defined as __________.
A) a segment of DNA that carries the instruction for one polypeptide chain.
B) noncoding segments of DNA up to 100,000 nucleotides long
C) an RNA messenger that codes for a particular polypetide
D) a three-base triplet that specifies a particular amino acid
Which structures are fingerlike projections that greatly increase the absorbing surface of cells?
A) primary cilia
A) function to digest particles ingested by endocytosis
B) are able to detoxify substances by enzymatic action
C) sometimes function as secretory vesicles
D) are also called microbodies, and contain acid hydrolases
Which of the following statements is correct regarding net diffusion?
A) the rate is independent of temperature
B) The greated the concentration gradient, the faster the rate
C) molecular weight of a substance does not affect the rate
D) the lower the temperature, the faster the rate