QTR 1 FINAL

What are buffers, and why are they important to life?

Buffers are substances that keep pH within a normal range. They are important to life because without them, our bodies would be in a different range of pH and we could die.

What is an ecosystem, and why should human beings preserve ecosystems?

An ecosystem is the interacting with the environment from the community. Humans should preserve ecosystems because modifying them greatly upsets their natural eating cycles.

All the organisms classified into the Domain _____ are _____.

Archaea; single-celled

Which of the following statements about fats in our diets is NOT true?

Fats have less than half of the caloric density of carbohydrates.

Polysaccharides, the complex carbs, break down into reduced/simple sugars during which of the following processes?

Hydrolysis

Which of the following is NOT one of the six elements that make up 95% of the body weight of organisms?

Iron

What is passed from generation to generation when organisms reproduce? What has to happen to the hereditary material DNA for evolution to occur?

When all living things reproduce, their genes are passed on to the next generation. For evolution, the hereditary material DNA must adapt to the ever-changing environment.

Hydrogen bonds form when....

a slightly negative atom is attracted to a slightly positive atom.

A nucleotide consists of all of the following EXCEPT...

an amine group.

Negative impacts on the biodiversity of healthy ecosystems have included ALL of the following activities EXCEPT:

an increase in the size and volume of barrier reefs.

The list that correctly indicates a sequence of increasing biological organization is:

atom, molecule, organelle, cell.

Describe the levels of biological organization.

atom: smallest unit of an element composed of electrons, protons, and neutrons. molecule: union of two or more atoms of the same or different elements. tissue: a group of cells with a common structure and function. organ: composed of tissues functioning together for a specific task. organ system: composed of several organs working together. organism: an individual; complex individuals contain organ systems. community: interacting populations in a particular area. ecosystem: a community plus the physical environment. biosphere: regions of the earth's crust, waters, and atmosphere inhabited by living things.

The action of disrupting the three-dimensional shape of a protein is called...

denaturation.

Arrange the following taxonomic categories from the most inclusive to the least inclusive.

domain, kingdom, phylum, class, order, family, genus, species.

As biological organization increases in complexity in living stems, each level acquires new ______ that are determined by the interactions between the individual parts.

emergent properties

Lipids are used by the body to perform all of the following functions EXCEPT...

enzyme action.

The theory that accounts for both the diversity and the unity of all living things is the theory of...

evolution.

Hydrolysis of a triglyceride produces...

fatty acids and glycerol.

The instructions for the organization and metabolism of living things are encoded in the...

genes.

Complex carbs are stored in animals in the form of...

glycogen.

The calcium ion _____.

has given away two electrons.

The great pattern of organization in nature is maintained primarily by....

the flow of energy from the Sun.

Homeostasis is...

the maintenance of normal internal conditions in a cell or an organism by means of self-regulating mechanisms.

Organisms/living things are best defined by all of the following except:

they are unorganized.

If a patient is injected with radioactive iodine, a radioisotope scan would show it appears in the....

thyroid.

An electrically neutral atoms with an atomic number of 7 will have ____ electron shells.

two

Fats which have one or more double bonds within their fatty acid tails are _____ fats.

unsaturated

An experiment is performed to determine if eating breakfast affects students' performance on exams. The experimental (independent) variable is ______.

whether or not the students have breakfast

Which bond is most easily broken?

A hydrogen bond.

Which of the following atomic number characterizes the element with the highest valence number?

10

A solution with a pH of 5 is _____ times more acidic than with a solution with a pH of 9.

10,000

If an atom has an atomic number of 17 and an atomic mass of 35, the number of neutrons in its nucleus equals _______.

18

Normal rainfall has a pH of ______.

5.6

Give an example of a controlled study. Name the experimental and responding variable.

A controlled study is a study that is separate from the outside world because the researchers want to make sure the variables are what is changing the results. The experimental variable is independent variable. The responding variable is the dependent variable.

On the pH scale, which numbers indicate whether a solution is basic/acidic/neutral.

Acidic: 1-6 Neutral: 7 Basic: 8-14

Which of the following statements is true?

All isotopes have the same number of protons.

How does evolution explain both the unity and the diversity of life?

All living things have the capacity to evolve, and the process of evolution constantly reshapes every species on the planet, potentially providing a way for organisms to persist, despite a changing environment.

Explain whether CO2 is an ionic or a covalent compound. Why does this arrangement satisfy all atoms involved?

CO2 is a covalent compound.

Which statement best describes the behavior of carbon?

Carbon can share pairs of electrons with as many as four other atoms.

What type of bond is formed when atoms share electrons?

Covalent

The genetic material that stores information about the order of amino acids in a protein is...

DNA.

What is an isotope? A radioactive isotope? Radioactivity is always considered dangerous. Why?

Isotopes are atoms of the same element that differ in numbers of neutrons. A radioactive isotope is an atom that, over time, release various types of energy in the forms of rays and subatomic particles. Radioactivity is considered dangerous because in high levels it can harm cells, cause cancer, and damage DNA.

Of what significance is the shape of molecules in organisms?

It is imperative to the structural and functional roles they play in living things. Our bodies need to recognize the shapes of the molecules in order to use them.

Aquatic organisms are able to survive the winter due to which specific property of water?

It is less dense as a solid than as a liquid.

What are the basic characteristics of life?

Living things are organized into sections. They can be unicellular or multicellular. (atoms, molecules, cells, tissues, organs, organ systems, organisms, population, community, ecosystem, biosphere). Each level has emergent properties, which are determined by the interactions between the individual parts. Living things require materials and energy. Sun and food can be sources of energy. Living things maintain homeostasis. It is imperative that an organism maintain a state of biological balance. Temperature, moisture level, acidity, and other physiological factors must remain within the tolerance range of the organism. Living things respond. Living things respond with the environment and also with other living things. The ability to respond often results in movement, which help ensure survival of the organism and allow it to carry on its daily activities. Living things reproduce and develop. Every type of living thing can reproduce. Living things have adaptations. Adaptations are modifications that make organisms better able to function in a particular environment. This can also cause evolution if the adaptations are consistently changing over a period of time.

Why do living things require an outside source of nutrients and energy? Describe these sources.

Living things require an outside source because they cannot acquire everything by themselves. These sources are things like food, sun, etc.

Which of the following statements best represent the role of mutations in natural selection?

Mutations fuel natural selection through the introduction of variable genes capable of being passed to new generations through reproduction.

Which of the following is a polymer?

Nucleic acid

Choose the association between monomer and polymer that is INCORRECT.

Nucleic acid-DNA

To which group of organic compounds do both DNA and RNA belong?

Nucleic acids.

Describe the series of steps involved in the scientific method.

Observation, hypothesis, experiment, conclusion, scientific theory.

Name the kinds of subatomic particles studied. What is their atomic mass unit, charge, and location in an atom?

P(amu=1)(+1)nucleus N(amu=1)(0)nucleus E(amu=0)(-1)electron cloud

The correct way to write the scientific name of the garden pea is...

Pisum sativum (in italics).

Which of the following is NOT one of the classes of primary organic molecules?

Salts

Explain the scientific name of an organism.

Scientists use binomial nomenclature. The first word is the genus, and the second word is the species designation. First letter of first word is capital and the second word is all lowercase. The whole thing is italicized. They are based on latin.

Which of the following has a basic pH?

Stomach antacids

How does natural selection result in adaptation to the environment?

The body selects the best traits of both parents to move on through their child. Over a period of time, this results in an adaptation.

Explain why water is a polar molecule. What does the polarity and shape of water have to do with its ability to form hydrogen bonds?

The shape makes it a polar molecule. That is, it has one side that is positively charged and one side that is negatively charged. There is a partially negative charge and a partially positive charge, which results in the formation of a hydrogen bond.

Which of the given statements is NOT true?

The theory of evolution does not provide an explanation for the origin and extinction of many different forms of life.

An experiment is performed to determine if a dietary supplement affects the weight gain of chickens. Which of the following variables should not be held constant?

The type of supplement.

Which of the following statements is true?

There are two polar covalent bonds in water.

In DNA, thymine always pairs with...

adenine.

The nucleotide based molecule that supplies energy for transport across a membrane is...

adenosine triphosphate

Name five properties of water, and relate them to the structure of water, including its polarity and hydrogen bonding between molecules.

high heat capacity high heat of evaporation water is a solvent cohesive and adhesive frozen water is less dense than liquid water these all relate to the polarity and hydrogen bonding because without one of these, water would not be the same molecule.

Your body's ability to maintain its temperature within a narrow range despite changes in the surrounding temperature is an example of...

homeostasis.

The two strands of nucleotides in DNA are held together by _____ bonds.

hydrogen

The two strands of DNA are held together by _____ between the purine and pyrimidine bases.

hydrogen bonds

The only atom that has a nucleus with no neutrons is....

hydrogen.

The process by which polymers are broken down into monomer subunits is called...

hydrolysis.

When a person uses creative thinking to combine isolated facts to arrive at an explanation for a natural event, he is using _____ reasoning.

inductive

The bond between two amino acids is...

known as a peptide bond.

The first step in the scientific method is...

make observations and consider previous data.

The cycling of nutrients through ecosystems depends on all of the following EXCEPT:

making observations and testing hypotheses.

The tree isotopes of carbon-12C, 13C, and 14C-have different numbers of ____.

neutrons

Hydrophobic molecules tend to be...

nonpolar.

The process that transforms solar energy into chemical energy in the bonds of organic molecules is called...

photosynthesis.

The number of _______ is always equal to the number of electrons in a neutral atom.

protons

What are the categories of classification? How does the domain Eukarya differ from domain bacteria and domain Archaea?

species, genus, family, order, class, phylum, kingdom, and domain. Domain bacteria and domain archaea contain prokaryotes, which lack the membrane-bounded nucleus found in the eukaryotes of domain Eukarya.

The three-dimensional shape of a polypeptide is referred to as its...

tertiary structure.