Biological Principles Exam 1

How many chromosomes did you inherit from your father?

23

Habitat loss has driven the population of the Florida panther (Puma concolor cougar) to extremely low numbers. Which mechanism of microevolution is likely at play in this species?

A drastic reduction in the population size has led to a much-reduced gene pool. Genetic drift: the bottleneck effect

What is the basic structure of a triglyceride?

A glycerol head and three fatty acid tails

What is the difference between a primary and a secondary source?

A primary source is the original material published by the scientists, whereas a secondary source is a description of the original material.

What are the monomers of proteins?

Amino acids

The Periodic Table of Elements contains 92 naturally occurring elements and a few more that have been artificially created. Which of the following statements best describes elements?

An element is a substance that cannot be broken down by chemical means. Elements make up all the matter on earth.

Why is life based on carbon-based molecules?

Because a single carbon can bond with up to four other atoms

Why is natural selection considered to be the most important mechanism of microevolution?

Because natural selection consistently leads to nonrandom adaptive changes in a population, it is considered the most important mechanism of microevolution.

What events can lead to offspring having a unique arrangement of their parents' genes?

Both crossing over and independent assortment

How do buffers minimize change in the pH of biological systems?

By absorbing H+ ions when there is an excess By donating H+ ions when there is a shortage

Proteins are diverse molecules that perform a wide variety of functions.

Catalyze reactions via enzymes Transport Movement

________ is the polysaccharide most commonly found in highly fibrous foods such as celery.

Cellulose

Which of the following processes generate genetic variation during sexual reproduction?

Crossing over Random fertilization Independent assortment

Which of the following statements regarding chemical reactions is false?

During a chemical reaction, atoms of one element can be converted into a different element.

Which of the following is the correct organizational hierarchy, from largest to smallest, in the hierarchical order of life? (Some levels have been omitted, so you are looking for the correct order.)

Ecosystem Community Population Organ Tissue Cell Molecule Atom

What does fitness mean when speaking in terms of evolution?

How many offspring an individual produces

What are the four stages of food processing, ordered from beginning to end?

Ingestion, digestion, absorption, elimination

What is typically the first step in the scientific method?

Making an observation

What produces genetically unique daughter cells?

Meiosis

Which of the following statements is correct?

Our body can make a subset of the 20 amino acids, and needs proper nutrition to acquire the ones it cannot make.

Which four elements make up the bulk of living cells?

Oxygen, carbon, hydrogen, and nitrogen

What moves the food from your mouth to your stomach when you swallow?

Peristaltic muscle contractions

Water "beads up" on synthetic fabric such as polyester but binds to cotton. What is the most likely explanation for this?

Polyester is nonpolar, whereas cotton is polar.

What is another name for the polymers of carbohydrates?

Polysaccharides

Which would have the highest concentration of CH bonds?

Saturated fat

Which of the following molecules is solid at room temperature?

Saturated fats

What are attached at the centromere?

Sister chromatids

Which of the following is not made from long chains of glucose?

Sucrose but, glycogen, cellulose and starch are made from long chains of glucose.

What kinds of molecules can be used as metabolic fuel to produce ATP?

Sugars, amino acids, and fatty acids

Select the most complete explanation of what the pH scale measures.

The concentration of hydrogen ions in an aqueous solution

What is crossing over?

The exchange of pieces of homologous chromosomes

Which accessory organ's secretions neutralize stomach acid before it reaches the intestines?

The pancreas

Oil hydrogenation can produce a product, such as vegetable shortening or margarine, that is spreadable at room temperature because of an unusual bond that does not occur naturally. What is the name of this category of lipid?

Trans fat

What is the difference between vitamins and minerals?

Vitamins are organic nutrients, while minerals are inorganic nutrients.

What is responsible for the unusual chemical properties of water?

Water molecules can form an extensive network of hydrogen bonds with one another.

A polypeptide is ________.

a long chain of amino acids

The main role of the large intestine is to ________.

absorb water

Something with a pH of 5 would be ________.

acidic

Which of the following features would be useful in identifying pseudoscience?

beliefs

This substance is stored in the gall bladder and released to aid in the digestion of fat.

bile

Which process requires DNA to undergo duplication before it can proceed?

both meiosis and mitosis

An essential nutrient is specifically a nutrient that your body ________.

cannot make by itself

The four classes of large organic molecules that are essential to life include __________.

carbohydrates, lipids, proteins, and nucleic acids

Organic compounds are distinguished by molecules that contain ________ bonded to other elements.

carbon

DNA plus its associated proteins is called a ________.

chromatin

Genes are located on ________.

chromosomes

The building of a large organic molecule from small subunits involves multiple ________.

dehydration synthesis reactions

Somatic cells are ________.

diploid (2n)

Meiosis starts with a single diploid cell and produces

four haploid cells.

Evolution that occurs by ________ results in a change in a population's gene pool due to the movement of individuals into and out of the population.

gene flow

Evolution that occurs by __________ results in a change in a population's gene pool due to chance.

genetic drift

The cardiovascular system consists of ________.

heart and blood vessels

During prophase I of meiosis,

homologous chromosomes stick together in pairs.

The breaking of a large organic molecule into smaller, individual subunits involves multiple ________.

hydrolysis reactions

All lipids are ________.

hydrophobic

Natural selection acts on ________, and ________ evolve.

individuals; populations

A cell preparing to undergo meiosis duplicates its chromosomes during

interphase.

The scientific method ________.

is a rough recipe for answering questions, but the steps need not always need to be performed in the same order

Digestion is ________.

mechanical and chemical

What produces four daughter cells?

meiosis

Evolution that occurs by ____________ results in nonrandom reproductive success and adaptive change.

natural selection

A scientist has collected data on the stomach contents of raccoons. He finds that they eat marsh grasses, crayfish, clams, insects, and food items discarded by people. What type of graph would be the best way to show the percentages of each of the components of the raccoons' diet?

pie chart

The main role of the liver is to ________.

produce bile, which helps the process of digestion

The correct order of events during meiosis is

prophase I, metaphase I, anaphase I, telophase I, cytokinesis, meiosis II.

During meiosis, segments of nonsister chromatids can trade places. This recombination of maternal and paternal genetic material is a key feature of meiosis. During what phase of meiosis does recombination occur?

prophase I.

During digestion, __________ are broken down into __________ through __________ reactions.

proteins; amino acids; hydrolysis

During a chemical reaction, atoms are ________.

rearranged

Most of the absorption of nutrients (besides water) takes place in the ________.

small intestine

What do you call an organism that has been genetically engineered to contain a gene from a different species?

transgenic

Like mitosis, meiosis involves duplication of the chromosomes before division starts. However, there are __________ rounds of cell division during meiosis and __________ during mitosis.

two; one