The process of forming mRNA is called?

• auscultation
• transcription
• replication
• translation
• ribolation

transcription

What structure organize the mitotic spindle during division?

• 5
• 2
• 3
• 1
• 6

2

Each triplet baes on a gene corresponds to

• one mRNA
• one protein
• one DNA nucleotide
• one amino acid in a protein
• one chromosome

one amino acid in a protein

Microfilament

• are found in the cytoplasm radiating away from the centrosome
• interact with filaments composed of tubulin to produce muscle contractions
• are usually composed of myosin
• anchor the cytoskeleton to integral proteins of the cell membrane
• are hollow, filamentous structures

• anchor the cytoskeleton to integral proteins of the cell membrane

cytology

the structure and function of cells

many protein in the cytosol are ________ that accelerate metabolic reactions

• carbohydrate
• messengers
• ions
• enzymes
• lipids

enzymes

Functions of plasma membrane include all the following except

• separation of cytoplasm from the extracellular fluid
• sensitivity to chemical change in the extracellular fluid
• regulation of exchange of material with the extracellular environment
• structural support
• thermal insulation

thermal insulation

Examination of a sample of glandular cells reveals an extensive network of smooth endoplasmic reticulum. Which of the following is the likeliest product of the cells?

• transport protein
• digestive enzymes
• antibodies
• protein hormones
• steroid hormones

steroid hormones

Which of the following best describes osmosis?

• active transport of water across the cell membrane
• diffusion of water from a greater to lesser water concentration across a selectively permeable membrane
• random movement of water due to kinetic energy
• movement of water into a solute
• diffusion of water from a greater to a lesser water concentration

diffusion of water from a greater to lesser water concentration across a selectively permeable membrane

The functional units of DNA that contain the instructions for making one or more proteins are

• chromosomes
• RNA
• ribosomes
• genes
• condons

genes

All of the following membrane transport mechanisms are passive processes except

• osmosis
• facilitated diffusion
• movement of water
• diffusion
• vesicular transport

vesicular transport

If a cell lacked the enzyme DNA polymerase, it could not

• maintain the integrity of the nuclear envelope
• form a new nuclear membrane during telophase
• form spindle fibers
• link segments of DNA together
• form complementary strands

form complementary strands of DNA during replication

Which of these substances could be driven across a membrane by the resting membrane potential?

• Na⁺
• CO₂
• glucose
• H₂O
• O₂

Na⁺

Embryonic stem cells might be used to replace neurons lost in Parkinson's Disease because

• they have not yet differentiated
• they are readily available
• they are taken from the brain of the embryo
• they divide quickly
• they are young and vigorous

they have not yet differentiated

Which of the following descriptors regarding cytoplasm false?

• contains less proteins then extracellular fluid
• syrupy or gel-like consistency
• includes cytoskeleton
• includes cytosol
• the material that fills a cell

contains less proteins then extracellular fluid

The enzyme ______ is required for the synthesis of mRNA

• RNA polymerase
• deoxyribose
• RNA synthetase
• ribose
• phosphatase

RNA polymerase

when telomeres get too short after repeated cell divisions.

• the cell dies
• the chromosomes uncoil
• the cell stops dividing
• the cell divides more frequently
• the cell become cancerous

the cell stops dividing

the endoplasmic reticulum is responsible for all of the following except

• lipid synthesis
• passing molecules to the Golgi apparatus
• drug and toxin neutralization
• modification of new proteins
• housing the chromosomes

housing the chromosomes