Principles of biology

What is the name of the enzyme that fits new complementary DNA nucleotides into the new strand?

DNA polymerase

In most organisms, the flow of information is from

DNA, RNA, then protein.

Sickle-cell disease results in misshapen red blood cells. What impact does this have on their ability to carry gases in the bloodstream.

It reduces their ability to carry oxygen, resulting in anemia.

What is the role of the enzyme ligase in DNA replication?

It seals any breaks in the sugar-phosphate backbone.

Meiosis proceeds different in males compared to females. Which of the following best describes one of those differences?

Spermatogenesis results in the production of four haploid sperm cells and oogenesis results in the production of a single haploid egg cell.

During the human life cycle, the fertilization of an egg by a sperm results in

a diploid zygote.

This trait is considered to be inheritable

eye color

Hemoglobin functions in _____ cells and carries ____ to all cells of the body.

red blood; oxygen

Getting a flu vaccine guarantees individuals will not get the flu. True or False?

False

Sickle-cell disease causes hemoglobin proteins to become altered. What direct effect does this have on red blood cells?

Red blood cells become sickle-shaped, clumping up and blocking blood flow in capillaries.

Which of the following most accurately describes how sickle-cell disease impacts the body?

Red blood cells clump up, blocking capillaries within the alveoli, resulting in acute chest syndrome, marked by pain, fever, and shortness of breath.

Humans have two sex chromosomes that are named based on their shape. Males have (a) _____ and females have (a) _____.

X and Y chromosome; two X chromosomes

Segments of DNA that contain instructions for making either proteins or RNA molecules that regulate proteins are called _____.

genes

Which of the following is the most effective means of treating or even curing sickle-cell disease?

Blood transfusions

A method of genome editing that uses the Cas9 enzyme to identify and cut specific nucleotides from the genome is called _____.

CRISPR (clustered regularly interspaced short palindromic repeats)

In humans, male gametes are called _____, while female gametes are called _____.

sperm; eggs

A single mutation causes sickle-cell disease. Which of the following statements best describes how this occurs?

A single nucleotide mutation causes a normal glutamine amino acid to be replaced with a valine amino acid. This causes the resulting hemoglobin protein to form incorrectly, resulting in sickle-shaped red blood cells that cannot function as intended.

Which of the following is a characteristic of all living things?

All living things breathe.

During gene therapy, bone marrow stem cells are removed from the individual. What must happen to those cells before they are injected back into the individual?

Viruses act as vectors to carry the normal gene into the genome of the stem cells.

all of the following are components of DNA.

a deoxyribose sugar;a phosphate group;the nitrogenous bases, thymine, adenine, cytosine, and guanine

All viruses are made up of two components. What are they?

a protein capsid and genetic material, in the form of either RNA or DNA

The following is the best definition of a gene?

a section of DNA that produces a single protein product

Sickle-cell disease is a disorder that is caused by...

a single mutation on a single gene.

CRISPR was discovered

accidentally, by scientists working with bacteria in the food industry. They were looking for ways to make cheese and yogurt production more effective.

Variations in genes are called _____. Examples of these variations include eye color. There are blue eyes, green eyes, brown eyes, and several combinations of these.

alleles

What is the correct sequence of events in viral reproduction?

attachment, penetration, biosynthesis, maturation and release

How are flu viruses named? Check all that may apply.

by their hosts;by their type (A or B)

Which of these is the best description of a virus?

chemical complexes of RNA or DNA protected by a protein shell

During prophase I of meiosis, genetic information is exchanged between two homologous chromosomes, resulting in new combinations of alleles. This process is called _____.

crossing-over

Which of the following types of cells would a flu virus most likely target as the means of entry into the body?

epithelial cells lining the respiratory system

In order to infect a cell, a virus must

have a special protein on its surface that can interact with a protein receptor on the surface of the host cell.

Images of unreplicated chromosomes that allow researchers to organize and identify each chromosome, as well as missing or extra chromosomes is called a(n) _____.

karyotype

Mendel's experiments led him to the conclusion that individuals have two factors for each trait that separate during gamete formation, resulting in gametes with one factor for each trait. In addition, fertilization results in a new individual with two factors for each trait again. He referred to this as the _____.

law of segregation

Sickle-cell disease results in malformed hemoglobin molecules. Which cell type contains millions of hemoglobin molecules per cell?

red blood cells

Meiosis is different from mitosis in that meiosis

results in four haploid daughter cells that are genetically diverse, whereas mitosis results in two diploid daughter cells that are genetically identical.

During translation, a polypeptide chain is created using a RNA template. Which of the following components is responsible for bringing amino acids to the growing polypeptide chain?

tRNA

Sickle-cell disease is a recessive genetic disease. This means

two copies of the recessive allele must be present in order for the disease to be expressed.