Chapter 4 Reading Questions

This figure illustrates a process by which the expression of a gene can be turned on (or off) according to the functions of cells or physiological needs. For example, casein is only produced when a mother is lactating. Name this process. 1. gene duplication 2. gene splicing 3. gene regulation 4. gene therapy

gene regulation

________________ is transmission of genetic characteristics from parent to offspring.

heredity

Which term refers to the protein "spools" that help organize DNA into nucleosomes? 1. clathrin 2. histones 3. polymerases 4. chaperones

histones

In a molecule of DNA, which two nitrogenous bases form two hydrogen bonds with each other. Select two answers below. 1. adenine 2. guanine 3. cytosine 4. uracil 5. thymine

- adenine - thymine

Which statements are true regarding the discovery of the double helix of DNA? Select all that apply. 1. Rosalind Franklin's X-ray diffraction showed that the DNA is a helix 2. Watson and Crick published their findings on the structure of the DNA without performing an experiments of their own 3. Watson, Crick, Wilkins, and Franklin received in 1962 the Nobel prize for their work on DNA

- Rosalind Franklin's X-ray diffraction showed that the DNA is a helix - Watson and Crick published their findings on the structure of the DNA without performing an experiments of their own

Which of the following may be the final product encoded by a gene? 1. protein 2. sugars 3. RNA 4. triglycerides

- protein - RNA

During translation, ______________ RNA delivers amino acids to the ribosome for protein synthesis. 1. messenger 2. ribosomal 3. transfer

transfer

Describe telophase. Select all that apply. 1. DNA is repicated 2. a nuclear envelope reappears 3. chromosomes align along the center of the cell 4. centrioles migrate to the poles of cell 5. chromatids cluster on each side of the cell

- a nuclear envelope reappears - chromatids cluster on each side of the cell

Which phase is an interval between cell division and DNA replication? During this time, a cell synthesizes proteins, grows, and accumulates the materials needed to replicate its DNA in the next phase. 1. G1 2. G0 3. M phase 4. S phase 5. G2

G1

Indicate which of the following is NOT part of interphase. 1. M 2. G2 3. S 4. G1

M

Where is RNA usually found?

cytoplasm

True or false. Proteins the must be packaged into a lysosome or secreted from the cell are synthesized in free ribosomes.

false

A(n) _____________ is an information-containing segment of DNA that codes for the production of a molecule of RNA, and that in most cases for one or more proteins.

gene

During DNA replication, the new short segments of DNA in one of the strands are joined together by the enzyme DNA ________________.

ligase

The location of a particular gene on a chromosome is called its ______.

locus

The location of a particular gene on a chromosome is called its ________________.

locus

During metaphase, the spindle fibers form a lemon-shaped array called the ____________________.

mitotic spindle

tRNA is short for ____________ RNA.

transfer

Using the figure as a guide, place the events of protein synthesis in order. 1. a template strand of DNA contains base triplets 2. anticodons of tRNA bind to the nRNA codons 3. codons of mRNA are translated from DNA triplets 4. amino acids are linked into a peptide chain

- a template strand of DNA contains base triplets - codons of mRNA are translated from DNA triplets - anticodons of tRNA bind to the nRNA codons - amino acids are linked into a peptide chain

Indicate which of the following statements are true about the G0 phase of the cell cycle. Select all that apply. 1. an inability to stop cycling and enter G0 is characteristic of cancer cells 2. the duration of this phase is variable (for some cells it may last days, years, or the rest of one's life) 3. during this phase cells leave the cell cycle for a "rest" and cease to divide 4. during this phase a cell makes a duplicate copy of its centrioles and all of its nuclear DNA 5. during this phase cells produce the enzymes needed for cell division and also check and repair the newly synthesized DNA

- an inability to stop cycling and enter G0 is characteristic of cancer cells - the duration of this phase is variable (for some cells it may last days, years, or the rest of one's life) - during this phase cells leave the cell cycle for a "rest" and cease to divide

Which of the following statements are true regarding introns? Select all that apply. 1. an intron is a portion of mRNA that does not code for protein 2. an intron is a portion of mRNA that must be removed before translation 3. an intron is a portion of mRNA that undergoes translation in the cytoplasm

- an intron is a portion of mRNA that does not code for protein - an intron is a portion of mRNA that must be removed before translation

Brown eye color requires which of the following? Select all that apply. 1. genes for the enzymes that synthesize the pigment melanin 2. phenylalanine, from which the melanin is made 3. one dominant allele and two recessive alleles

- genes for the enzymes that synthesize the pigment melanin - phenylalanine, from which the melanin is made

Anticodons are found on which type of molecule? 1. mRNA 2. protein 3. tRNA 4. ribosome

tRNA

Match each nitrogenous base with its decsription. 1. cytosine 2. adenine 3. thymine 4. guanine 1. purine that binds with thymine 2. pyrimidline that binds with adenine 3. purine that binds with cytosine 4. pyrimidline that binds with guanine

cytosine - pyrimidline that binds with guanine adenine - purine that binds with thymine thymine - pyrimidline that binds with adenine guanine - purine that binds with cytosine

Changes to the structure of a new protein (i.e removal of some amino acids, folding of the protein, adding carbohydrates, etc.) are collectively known as what? 1. incomplete dominance 2. posttranslational modification 3. semiconservative replication 4. alternating splicing

posttranslational modification

Which of the following best summarizes the role of DNA in protein synthesis? 1. the anticodons of DNA bind directly to amino acids, allowing them to be linked into a peptide chain 2. DNA contains the genetic code that determines the amino acid sequence of proteins 3. DNA acts as an enzyme to catalyze the conversion of mRNA into protein 4. DNA guides the folding of a new protein after it has been assembled by RNA

DNA contains the genetic code that determines the amino acid sequence of proteins.

DNA is a polymer of ______________, each of which consists of a phosphate, a sugar, and a single or double-ringed nitrogenous base.

nucleotides

Which enzyme is responsible for transcribing DNA? 1. helicase 2. RNA polymerase 3. DNA ligase 4. DNA polymerase

RNA polymerase

Name the period of synthesis during which a cell makes a duplicate copy of its centrioles and all of its nuclear DNA. 1. S phase 2. Telophase 3. M phase 4. G1 phase

S phase

Alternative forms a gene are known as _______________.

allele

During translation, transfer RNA (tRNA) binds which molecule in the cytosol and delivers it to the ribosome? 1. amino acid 2. DNA 3. anticodon 4. codon

amino acid

At one end of each tRNA there is a sequence of three nucleotides known as the ____________. This sequence is complementary to the bases on mRNA.

anticodon

A three-base sequence of mRNA is called a ______________.

codon

Exposure to chemicals and radiation may lead to changes in DNA structure called ______________.

mutations

The ________________ bases in DNA are adenine, cytosine, guanine, and thymine.

nitrogenous

During translation, ________________ RNA delivers amino acids to the ribosomes for protein synthesis. 1. messenger 2. ribosomal 3. transfer

transfer

The process of reading an mRNA molecule and synthesizing the protein encoded in its nucleotide sequence is known as ______________.

translation

A base _____________ is a consecutive sequence of three DNA nucleotides that codes for one amino acid.

triplet

Which of the following refers to a 3-base sequence found in tRNA? 1. amino acid 2. codon 3. anticodon 4. mRNA

anticodon

Which chromosomes do not determine the sex of an individual? 1. gametes 2. diploid 3. alleles 4. autosomes

autosomes

Match the event during protein processing and secretion with the letter indicated in the figure. 1. protein formed by ribosomes on rough ER 2. protein packaged into transport vesicle, which buds from ER 3. transport vesicles fuse into clusters that unload protein into golgi complex 4. golgi complex modifies protein structure 5. secretory vesicles release protein via exocytosis 1. A 2. B 3. C 4. D 5. E

protein formed by ribosomes on rough ER - A protein packaged into transport vesicle, which buds from ER - B transport vesicles fuse into clusters that unload protein into golgi complex - C golgi complex modifies protein structure - D secretory vesicles release protein via exocytosis - E

If a protein is going to be used in the cytosol, it is likely to be made by ______. However, if it is going to be secreted from the cell, it is made by ______ on the RER.

free ribosomes; polyribosomes

Regulatory proteins turn these on and off in accordance with changing needs for the proteins they encode. 1. robosomes 2. enzyme 3. genes 4. proteins

genes

The form of cell division in which a cell divides once and produces two genetically identical daughter cell is known as _______________.

mitosis

When a cell replicates its nucleus and then pinches in two to form two new daughter cells it is said to be in M phase, also called the _____________ phase, of the cell cycle.

mitosis

Transcription is the process of copying genetic instruction from a molecule of _____________ to mRNA.

DNA

The division of the cytoplasm to form two cells is called ________________.

cytokinesis

Place the phases of the cell cycle in the correct order starting with G1. 1. S 2. G2 3. G1 4. M

- G1 - S - G2 - M

Susie is not color-blind, but she transmitted a color-blindness gene to her son. She is said to be a ______ of the color blindness gene.

carrier

Cell division is stimulated by _____________ and suppressed by ______________. 1. growth factors; contact inhibition 2. contact inhibition; cytokinesis 3. cell size; contact inhibition 4. cell number; growth factors

growth factors; contact inhibition

The X and Y chromosomes are referred to as which of the following? 1. sex chromosomes 2. karyotypes 3. semiconserative chromosomes 4. autosomes

sex chromosomes

Which of the following statements are true regarding the DNA structure? Select all that apply. 1. each side piece is a sugar-phosphate backbone composed of phosphate groups alternating with the sugar deoxyribose 2. the nitrogenous bases face the inside and hold the two backbones together with hydrogen bonds 3. the basic three-dimensional structure of DNA is the double helix 4. hydrogen bonds can form either between two purines or else between two pyrimidines

- each side piece is a sugar-phosphate backbone composed of phosphate groups alternating with the sugar deoxyribose - the nitrogenous bases face the inside and hold the two backbones together with hydrogen bonds - the basic three-dimensional structure of DNA is the double helix

Put the steps of mitosis in the correct order. 1. metaphase 2. prophase 3. telophase 4. anaphase

- prophase - metaphase - anaphase - telophase

Indicate which of the following events occur during prophase of mitosis. Select all that apply. 1. spindle fibers grow from the centrioles 2. chromosomes migrate to opposite poles 3. chromosomes condense 4. nuclear envelope 5. centrioles are pushed apart

- spindle fibers grow from the centrioles - chromosomes condense - nuclear envelope - centrioles are pushed apart

What is a cleavage furrow? 1. a centriole-containing region of cytoplasm adjacent to the cell nucleus 2. a specialized structure on the centomere to which the microtubular spindle fibers attach during mitosis and meiosis 3. an assembly of microtubules, which function in the formation of the spindle apparatus during cell division 4. an indentation between the future cells that forms as cytokinesis progresses

an indentation between the future cells that forms as cytokinesis progresses

All the codon and non coding DNA found in haploid number of chromosomes from one organism is known as the ______________.

genome

Each daughter DNA consists of one new strand (synthesized from free nucleotides) and one old strand (conserved from the parental DNA). This process is called _______________ replication.

semiconservative

Translation occurs in three steps. choose the names steps from the list below. Select all that apply. 1. transcription 2. initiation 3. elongation 4. termination 5. replication

- initiation - elongation - termination

Which of the following statements is true regarding type O blood? Select all that apply. 1. individuals with type O blood do not produce red blood cells 2. it is caused by the recessive allele 3. individuals with type O blood are homozygous for this trait 4. it is the rarest blood type in North America

- it is caused by the recessive allele - individuals with type O blood are homozygous for this trait

Which of the following are involved in the initiation step of translation? Select all that apply. 1. RNA polymerase 2. methionine 3. ribosomal subunits 4. initiator tRNA 5. DNA 6. mRNA

- methionine - ribosomal subunits - initiator tRNA - mRNA

Put the following steps in order to show how the hormone prolactin car regulate gene expression. 1. casein gene is transcribed 2. regulatory protein binds to DNA and atteacts RNA polymerase 3. prolactin binds to its receptor 4. regulator is activated and enters nucleus 5. mRNA moves to cytoplasm and it translated to produce casein protein

- prolactin binds to its receptor - regulator is activated and enters nucleus - regulatory protein binds to DNA and atteacts RNA polymerase - casein gene is transcribed - mRNA moves to cytoplasm and it translated to produce casein protein

If the mother is a carrier for hemophilia (X-linked trait) but the father does not have this condition, what is the chance that their son will have the disease? 1. 75% 2. 0% 3. 50% 4. 25%

50%

At one end of each tRNA there is a sequence of three nucleotides known as the ______________. This sequence is complementary to the bases on mRNA.

anticodon

Name the protein that guides newly synthesized proteins in folding into their proper shape and helps to present improper associations between different proteins.

chaperone

Since there are no genes coding for carbohydrates, nucleic acids, or lipids, how do cells produce them? 1. cells are produced with all the products they need 2. cells obtain all of these products by endocytosis 3. cells can produce carbohydrates, nucleic acids, and lipids out of proteins 4. genes encode enzymes that synthesize these proteins

genes encode enzymes that synthesize these proteins

When synthesized proteins are to be exported out of the cells, they can be packaged into secretory vesicles that originate in what organelle? 1. ribosomes 2. nucleus 3. golgi complex 4. smooth endoplasmic reticulum

golgi complex

One mRNA can have several ribosomes attached to it at one time during translation of mRNA. Which term refers to this cluster of ribosomes? 1. core particle 2. polyribosome 3. translation complex 4. ribosomal unit

polyribosome

The nuclear envelope is perforated with openings called nuclear ________________ that regulate the movement of molecules through the envelope.

pores

When a cell is preparing to divide, it makes an exact copy of all its nuclear DNA. Each chromosome then consists of two parallel filaments called ______________.

sister chromatids

In DNA, the base adenine pairs with the base ________________.

thymine

During the process of translation, the three-nucleotide sequence (AUG) serves as a code for methionine and also as a ________________ codon that signals the beginning of a new protein.

start

Why are sperm and egg cells said to be haploid? 1. they contain 46 chromosomes 2. they contain only 12 pairs of homologous chromosomes 3. they contain only X or Y chromosomes 4. they contain only 23 unpaired chromosomes

they contain only 23 unpaired chromosomes

Match the nucleic acid with its description. 1. Deoxyribonucleic acid (DNA) 2. Ribonucleic acid (RNA) 1. it contains a sugar called deoxyribose, it contains nitrogenous bases A, T, C, G; it consists of two nucleotide chains (double helix); it functions in the nucleus; it codes for synthesis of RNA and protein 2. it contains a sugar called ribose; it contains nitrogenous bases A, U, C, G; it consists of one nucleotide chain; it functions mainly in the cytoplasm; it carries out the instructions in DNA

Deoxyribonucleic acid (DNA) - it contains a sugar called deoxyribose, it contains nitrogenous bases A, T, C, G; it consists of two nucleotide chains (double helix); it functions in the nucleus; it codes for synthesis of RNA and protein Ribonucleic acid (RNA) - it contains a sugar called ribose; it contains nitrogenous bases A, U, C, G; it consists of one nucleotide chain; it functions mainly in the cytoplasm; it carries out the instructions in DNA

Which phase is a short period of time of growth and preparation for mitosis? During that time, the cell produces enzyme that control cell division, and also checks and repairs the newly copied DNA. 1. G2 2. M 3. G2 4. S

G2

Cells contain pairs of chromosomes. Since they are the same size and shape and also code for the same information, each pair of chromosomes is called which of the following? 1. autosomes 2. dipoid chromosomes 3. sex chromosomes 4. homologous chromosomes

homologous chromosomes

Which molecule carries the genetic code from the nucleus to the cytoplasm? 1. DNA 2. rRNA 3. mRNA 4. tRNA

mRNA

Males are more likely than female to inherit a genetic disease if the gene for it is which of the following? 1. dominant 2. polygenic 3. pleiotropic 4. mutated 5. x-linked

x-linked

Based on the information in this table, which of the following are true? Check all that apply. 1. each amino acid is always represented by the same codon 2. each codon always represents that same amino acid 3. more than one codon can represent the same amino acid 4. each codon is three nucleotides long

- each codon always represents that same amino acid - more than one codon can represent the same amino acid - each codon is three nucleotides long

Which of the following are true regarding the cell cycle? Select all that apply. 1. the cell cycle is programmed and generally takes no more than 1-2 hours 2. some cells like stomach and skin cells divide rapidly 3. some cells leave the cell cycle for a "rest" and cease to divide for days, years, or rest of one's life

- some cells like stomach and skin cells divide rapidly - some cells leave the cell cycle for a "rest" and cease to divide for days, years, or rest of one's life

This is the normal karyotype of a human male. How many pairs of autosomes are shown? 1. 1 2. 22 3. 23 4. 46

22

Match the letter indicated in the figure with the name of the structures participating in DNA replication. 1. A 2. B 3. C 4. D 5. E 1. daughter DNA 2. DNA ligase 3. DNA polymerase 4. DNA helicase 5. parental DNA

A - parental DNA B - daughter DNA C - DNA polymerase D - DNA helicase E - DNA ligase

Refer to the table. Match the base triplet of DNA to the amino acid specified by the genetic code. 1. CCA 2. CGT 3. TGC 4. GTA 1. histidine 2. glycine 3. threonine 4. alanine

CCA - glycine CGT - alanine TGC - threonine GTA - histidine

Match each protein with its role during DNA replication. 1. DNA helicase 2. DNA polymerase 3. DNA ligase 1. reads nitrogenous bases and matches them with complementary free nucleotides 2. opens the DNA helix exposing the nitrogenous 3. joins the newly synthesized segments of DNA

DNA helicase - opens the DNA helix exposing the nitrogenous DNA polymerase - reads nitrogenous bases and matches them with complementary free nucleotides DNA ligase - joins the newly synthesized segments of DNA

________________ is the last step of translation. In this step, a stop codon is reached and the A site binds a release factor which causes the newly-synthesized polypeptide to be released from the ribosome.

Termination

Which of the following best describes a nucleosome? 1. a tRNA molecule and its appropriate amino acid 2. a short stretch of DNA partly wrapped around a spool of histones 3. an mRNA molecule and many attached ribosomes 4. a group of nucleoli in the nucleus where ribosome are produced

a short stretch of DNA partly wrapped around a spool of histones

When a red flower crossed with a white flower produces a pink flower, which of the following is demonstrated? 1. peliotropy 2. codominance 3. incomplete dominance 4. polygenic inheritance

incomplete dominance

_______________ is a term that means the percentage of a population with a given genotype that actually exhibits the predicted phenotype.

penetrance

Name the process by which a cell makes a copy of its DNA so it can give complete and identical copies of all of its genes to each daughter cell.

replication

Which of the following statements about codons are true? 1. every codon codes for an amino acid 2. a codon is a three-base sequence of mRNA 3. the genetic code is expressed as a sequence of codons 4. a codon is the three-base sequence of tRNA

- a codon is a three-base sequence of mRNA - the genetic code is expressed as a sequence of codons

At three specific checkpoints during the cycle cell a cyline binds to a Cdk and activates a series of reactions that allow the cell to move on the next phase. When in the cell cycle do these checkpoints occurs? Select three answers from the list below. 1. at the end of prophase 2. between the S and G2 phase 3. during the G1 phase 4. at the end of metaphase 5. late in the G2 phase

- during the G1 phase - at the end of metaphase - late in the G2 phase

What is the role of mRNA in protein synthesis? 1. it opens the DNA helix and reads the bases from one strand of DNA 2. it carries the genetic code from the nucleus to the cytoplasm 3. it stays within the nucleus and serves ad the template for transcription 4. it binds free amino acids and delivers them to the ribosome to be added to a growing proteins chain

it carries the genetic code from the nucleus to the cytoplasm

Which of the following is true about the centromere? 1. it is what chromosomes attach to, so they can be pulled to the middle of the cell 2. it is located at the tips of the chromosome "arms" 3. it is where sister chromatids are joined together 4. it is a short stetch of DNA wrapped around a cluster of histone proteins

it is where sister chromatids are joined together

Egg and sperm cells (or their precursors) are called germ cells. All other cells in the body are called _______________ cells.

somatic

During DNA replication, the enzyme DNA ______________ opens up a short segment of the helix, exposing its nitrogenous bases.

helicase

Which term refers to individuals with two identical alleles for a particular trait? 1. homologous 2. haplioid 3. homozygous 4. heteroztgous

homozygous

Which of the following statements are true concerning the first tRNA to bind to a ribosome at the start of translation. 1. it is called the initiator tRNA 2. it carries one of three possible start codons 3. its anticodon is complementary to the codon AUG (the start codon) 4. it always carries the amino acid alanine

- it is called the initiator tRNA - its anticodon is complementary to the codon AUG (the start codon)

Chromatin appears divided into segments called ___________ consisting of a core particle and a short segment of linker DNA leading to the next core particle.

nucleosomes

Place these events in the order they occur during protein processing and secretion. 1. transport vesicles unload protein into Golgi complex 2. Golgi complex modifies protein structure 3. protein packaged into transport vesicles, which bud from ER 4. protein formed by ribosomes on RER 5. secretory vesicles release protein by exocytosis

- protein formed by ribosomes on RER. - protein packaged into transport vesicles, which bud from ER - transport vesicles unload protein into Golgi complex - golgi complex modifies protein structure - secretory vesicles release protein by exocytosis.

Place the steps of translation in the correct order, starting with what happens first. 1. the ribosome binds mRNA 2. a new amino acid is linked to the growing peptide chain 3. a tRNA anticodon binds to a complementary mRNA codon 4. the tRNA is released from the ribosome and is now available to pick up another amino acid

- ribosome bind mRNA - tRNA anticodon binds to complementary mRNA codon - New amino acid is linked to the growing peptide chain - tRNA released from ribosome, available to pick up another amino acid

Describe ribosomes select all that apply. 1. ribosomes are found in the cytosol and on rough ER. 2. ribosomes play an important role in the process of transcription 3. ribosomes are made up of subunits that come together only when translating mRNA 4. ribosomes contain anticodond, 3-nucleotide sequences that are complementary to mRNA codons 5. each ribosome is composed of several enzymes and ribosomal RNA (rRNA) molecules

- ribosomes are found in the cytosol and on rough ER. - ribosomes are made up of subunits that come together only when translating mRNA - each ribosome is composed of several enzymes and ribosomal RNA (rRNA) molecules

List two characteristics of genes. 1. some genes overlap each other, so some of DNA belong to two different genes 2. every individual protein in the body is coded by a separate gene 3. some genes produce RNA molecules that do not synthesize proteins

- some genes overlap each other, so some of DNA belong to two different genes - some genes produce RNA molecules that do not synthesize proteins

Which of the following are components of nucleotides? Select all that apply. 1. sugars (ribose or deoxyribose) 2. amino acids 3. nitrogenous bases 4. phosphate groups 5. proteins

- sugars (ribose or deoxyribose) - nitrogenous bases - phosphate groups

Why is cancer more common in the elderly? Select all that apply. 1. the DNA and tissue repair mechanisms are less efficient as we age 2. the immune system grows stronger with more tendency to destroy malignant cells 3. mutations accumulate over time

- the DNA and tissue repair mechanisms are less efficient as we age - mutations accumulate over time

Which of the following statements about codons are true? 1. a codon is a three-base sequence of tRNA 2. the genetic code is expressed as a sequence of codons 3. every codon codes for an amino acid 4. a codon is the tree-base sequence of mRNA

- the genetic code is expressed as a sequence of codons - a codon is the tree-base sequence of mRNA

Indicate which of the following is true with regard to recessive alleles. Select all that apply. 1. their expression is masked in the presence of a dominant allele 2. they are more frequently observed in males than females 3. they mask the expression of other alleles 4. they are expressed only when present on both of the homologous chromosomes 5. they are more frequently expressed than other traits

- their expression is masked in the presence of a dominant allele - they are expressed only when present on both of the homologous chromosomes

Describe chaperones. Select all that apply. 1. they help prevent improper association between different proteins 2. they aid a newly synthesized protein in folding to its proper shape 3. some are also known as stress proteins or heat shock proteins 4. they degrade newly synthesized polypeptides that contain inaccurate sequence 5. they facilitate binding of ribosomes to mRNA

- they help prevent improper association between different proteins - they aid a newly synthesized protein in folding to its proper shape - some are also known as stress proteins or heat shock proteins

When do cells divide? Select all that apply. 1. when they snugly contact neighboring cells or when nutrients or growth factors are withdrawn 2. when neighboring cells die, opening up space in a tissue to be occupied by new cells 3. when they have replicated their DNA, so they can give each daughter cell a duplicate set of genes 4. when they grow large enough to have enough cytoplasm to distribute to their two daughter cells

- when neighboring cells die, opening up space in a tissue to be occupied by new cells - when they have replicated their DNA, so they can give each daughter cell a duplicate set of genes - when they grow large enough to have enough cytoplasm to distribute to their two daughter cells

In the nucleus, DNA is complexed with proteins to form a fine filamentous material called _____________.

chromatin

In the nucleus of a typical human cell, there are 46 DNA filaments. Which term refers to one of theses structure? 1. chromatin 2. nucleosome 3. chromosome 4. nucleolus

chromosome

After proteins are synthesized, some remain in the cell and some are secreted. Match each protein with its destination and function. 1. digestive enzymes 2. sodium-potassium pumps 3. kinases, ATPases 4. histones, RNA polymerase 1. delivered to the plasma membrane 2. return to the nucleus for cellular metabolism 3. used in the cytosol as metabolic enzymes 4. secreted by exocytosis

digestive enzymes - secreted by exocytosis sodium-potassium pumps - delivered to the plasma membrane kinases, ATPases - used in the cytosol as metabolic enzymes histones, RNA polymerase - return to the nucleus for cellular metabolism

Which term refers to the expression of genes as an observable trait (such as eye color)? 1. heterotype 2. karyotype 3. phenotype 4. genotype

phenotype

True or false. It is possible to predict the sequence of one strand of DNA if we know the sequence of the complementary strand.

true