Biology midterm 2013

309 terms by krngriffith 

Create a new folder

Advertisement Upgrade to remove ads

Prentice Hall midterm

autotrophs

organisms such as plants, which make their own food from sunlight or chemicals

heterotrophs

organisms, such as animals, that obtain energy from the foods they consume

Where do plants get the energy they need to produce food?

Plants and some other types of organisms are able to use light energy from the sun to produce food.

What is the role of ATP (adenosine triphosphate) in cellular activities?

ATP is used by all types of cells as their basic energy source.

photosynthesis

process by which plants and some other organisms use light energy to convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugars and starches

What did the experiments of van Helmont, Priestly, and Ingenhousz reveal about how plants grow?

In the presence of light, plants transform carbon dioxide and water into carbohydrates, and they also release oxygen.

What is the overall equation for photosynthesis?

carbon dioxide + water —> sugars + oxygen

What is the role of light and chlorophyll in photosynthesis?

Light is a form of energy and chlorophyll absorbs light and the energy from the light.

chlorophyll

principal pigment of plants and other photosynthetic organisms; captures light energy

Plants gather the sun's energy with light-absorbing molecules are called...

pigments

What happens in the light-dependent reactions?

... use energy from sunlight to produce ATP, NADPH, and oxygen. It takes place within the thylakoid membranes of chloroplasts.

What is the Calvin cycle?

... uses ATP and NADPH from the light-dependent reations to produce high-energy sugars. It takes place in the stroma of chloroplasts and does NOT require light.

thylakoid

saclike photosynthetic membranes found in chloroplasts

Proteins in the thylakoid membrane organize chlorophyll and other pigments into clusters known as...

photosystems

stroma

the region outside the thylakoid membranes in chloroplasts

NADP+

(nicotinamide adenine dinucleotide phosphate) one of the carrier molecules that transfers high-energy electrons from chlorophyll to other molecules.

light-dependent reactions

reactions of photosynthesis that use energy from light to produce ATP and NADPH

ATP synthase

large protein that uses energy from H+ ions to bind ADP and a phosphate group together to produce ATP

Which are autotrophs?

plants, mushrooms

One of the principal chemical compounds that living things use to store energy is...

ATP

Which scientist concluded that most of a growing plant's mass comes from water?

van Helmont

In addition to light and chlorophyll, photosynthesis requires...

water and carbon dioxide

The leaves of a plant appear green because chlorophyll...

reflects green light

The products of photosynthesis are...

sugars and oxygen

The first process in the light-dependent reactions of photosynthesis is...

ATP formation

Which substances from the light-dependent reactions of photosynthesis is a source of energy for the Calvin cycle?

ATP & NADPH

The light dependent reactions of photosynthesis are also known as the...

Calvin cycle

How do heterotrophs and autotrophs differ in the way they obtain energy?

heterotrophs obtain energy from the food they eat.

autotrophs obtain energy from the sunlight

Describe the three parts of an ATP molecule.

Adenine
Ribose
3 Phosphate groups

Use the analogy of battery to explain how energy is stored in and released from ATP.

ATP can be compared to a fully charged battery because both contain stored energy.

Compare the amounts of energy stored by ATP and glucose. Which compound is used by the cell as an immediate source of energy.

- A single molecule of the sugar glucose stores more than 90 times the chemical energy of a molecule of ATP.
- ATP is used as an immediate source of energy.

How were Priestley's and Ingenhousz's discoveries about photosynthesis related?

They both showed that light was necessary for plants to produce oxygen.

Write the basic equation for photosynthesis using the names of the starting and final substances of the process.

6CO2 + 6H20 —> C6H12O6 + 6O2
carbon dioxide + water —> sugars + oxygen

(NOTE: —> is light)

What role do plant pigments plan in the process of photosynthesis?

They gather the sun's energy

Explain the role of NADP+ as an energy carrier in photosynthesis.

It transfers high-energy electrons from chlorophyll to other molecules.

What is the role of ATP synthase? How does it work?

they provide the energy to build energy - containing sugars from low - energy compounds.
It allows hydrogen ions out of the thylakoid

Summarize what happens during the Calvin cycle.

plants use the energy that ATP and NADPH contain to build high-energy compounds that can be stored for a long time.

How do the events in the Calvin cycle depend on the light-dependent reactions?

The Calvin cycle uses ATP and NADPH from the light-dependent reactions to produce high-energy sugars.

Describe three factors that affect the rate at which photosynthesis occurs.

- water
- temperature
- intensity of light

the ability to do work

energy

All living things require...

energy

Autotrophs are plants and some other types of organisms are able to use ________ from the sun to produce _________.

- light energy
- food

autotrophs

Plants and some other types of organisms are able to use light energy from the sun to produce food.

heterotrophs

organisms that obtain their energy from food they consume

Energy comes in many different forms. Give examples.

- light
- heat
- electrically
- chemical compounds

Living things use chemical compounds stored and released in cells called...

ATP or adenosine triphosphate

ATP (adenosine triphosphate) contains...

a 5 carbon sugar (ribose) & 3 phosphates

ATP (adenosine triphosphate)

ADP lacks the third phospate make it ...

di-phosphate

Cells store the ______ until energy is needed by adding the third phosphate.

ADP

When the bond is broken between the 2nd and 3rd phosphate, ______ is released.

energy

The release of energy when the bond is broken between the 2nd and 3rd phosphate power these functions:

- active transport
- muscle contractions
- protein synthesis

The characteristics of ATP make it exceptionally useful as the basic _____ source of cells.

energy

ADP + phosphate —>(energy)—> ATP

Active transport

Sodium (Na) Potassium (K) pump maintaining ions on both sides of the cell

Cells only keeps a small amount of _____ .
Why?

- ATP
- ATP does not store easily

________ stores 90 times more chemical energy than a molecule of ATP.

Glucose

When plants use the energy of sunlight to convert water and carbon dioxide into high-energy carbohydrates (sugar and starches) and a waste product (oxygen).

photosynthesis

Helmont

scientist who concludes the trees gain most of their mass from water

Priestly

scientist who finds that plants release oxygen

Ingenhousz

scientist who finds that aquatic plants produce oxygen bubbles in the light but not in dark. Conclusion: plants need light to produce oxygen

Mayer

scientist who proposed plants convert light energy into chemical energy

Calvin

scientist who traces chemical path that carbon follows to form glucose (Calvin cycle)

Marcus

scientist who describes the process of electron transfer from molecule to electron transport chain

Photosynthesis Equation

- Reactants —> Products
- Carbon Dioxide + water in the presence of light yields sugars & oxygen

In addition to water and carbon dioxide, photosynthesis requires ________ and _________, a molecule in chloroplasts.

light and chlorophyll

Light is in ___________ form and creates a spectrum from ________ to ______.

- wavelength form
- violet to red

pigments

light absorbing molecules in plants

chlorophyll

the principle pigment in plants

2 main types of chlorophyll:

chlorophyll a & chlorophyll b

__________ (green) absorbs the blue-violet and red ends of the spectrum and transfers it to the electrons. While other pigments like __________ absorb the other color.

- Chlorophyll
- carotene

Where does photosynthesis take place?

in chloroplasts

Chloroplasts contain tiny sacs like photosynthetic membranes called...

thylakoids

Thylakoids are arranged in stacks known as ...

grana

Pigments are arranged into clusters known as ...

photosystems

What are the light collecting units in the chloroplasts?

photosystems (clusters of pigments)

What are the 2 Photosystems reactions?

- (1) light dependent (takes place in the thylakoids)

- (2) light independent or Calvin cycle (takes place in the stroma - the region outside the thylakoid membranes)

Sunlight excites the electrons in ________.

chlorophyll

The excited electrons and their energy must be transported by an electron carrier, like _______. This electron carrier can hold ______ electrons and an ion of _________. It is converted into _________ which is trapping sunlight energy into _______ energy. This is the electron ________ _______.

- NADP+
- 2 electrons
- hydrogen (H+)
- NADPH
- chemical energy
- electron transport chain

Light dependent reactions produce _______ ________ and convert _____ and _______ into the energy carriers ______ and _______.

... oxygen gas and convert ADP and NADP+ into the energy carriers ATP and NADPH.

Light independent cycle

takes in the stroma and outside the grana

The Calvin cycle uses ______ and ______ from the light-dependent reactions to produce high energy sugars.

ATP and NADPH

3 factors that affect photosynthesis:

- water supply
- temperature
- intensity of light

science

organized way of using evidence to learn about the natural world; also, the body of knowledge that scientists have built up after years of using this process

observation

use of one or more of the senses-sight, hearing, touch, smell, and sometimes taste - to gather information

data

evidence; information gathered from observation

inference

logical interpretation based on prior knowledge and experience

hypothesis

possible explanation for a set of observations or possible answer to a scientific question

spontaneous generation

hypothesis (disproven) stating that life could arise from non-living matter.

controlled experiment

a test of the effect of a single variable by changing it while keeping all other variables the same

manipulated variable

factor in an experiment that a scientist purposely changes; also knows as independent variable.

responding variable

factor is an experiment that a scientist wants to observe, which may change in response to the manupulated variable; also known as a dependent variable.

theory

well-tested explanation that unifies a broad range of observations.

Biology

Science that seek to understand the living world.

Cell

Collection of living matter enclosed by a barrier that separates the cell from its surroundings; basic unit of all forms of life.

Homeostasis

Process by which organisms maintain a relatively stable internal environment.

Sexual reproduction

Process by which cells from two different parents unite to produce the first cell of a new organism

Asexual reproduction

Process by which a single parent reproduces by it self

Metabolism

Set of chemical reactions through which an organism builds up or breaks down materials as it carries out its life processes.

Stimulus

A signal to which an organism responds.

Metric system

decimal system of measurement based on certain physical standards and scaled on multiples of 10

Microscope

Device that produces magnified images of structures that are too small to see with the unaided eye.

Compound light microscope

Microscope that allows light to pass through a specimen and uses two lenses to form an image.

Electron microscope

Microscope that forms an image by focusing beams of electrons onto a specimen.

Cell culture

group of cells grown in a nutrient solution from a single original all.

Cell fractionation

Technique in which cells are broken into pieces and the different cell part are separate

atom

the basic unit of matter

subatomic particles

protons, neutrons and electrons

protons

positively charged particles in the nucleus

neutrons

particles with no charge in the nucleus

electrons

negatively charged particles in constant motion outside the nucleus

why atoms are uncharged

atoms have equal numbers of protons and electrons

chemical element

a pure substance that consists entirely of one type of atom

atomic number

the number of protons in an atom of an element

isotopes

atoms of the same element that differ in the number of neutrons

compound

substances formed by the chemical combination of two or more elements in definite proportions

chemical formula

shorthand to show the chemical composition of a compound

chemical bonds

hold atoms in compounds together; the main types are ionic and covalent

ionic bond

a bond formed when one or more electrons are transfered from one atom to another

ion

a positively or negatively charged atom

covalent bond

a bond formed when electrons are shared between atoms

molecule

a structure that results when atoms are joined together by covalent bonds; the smallest unit of most compounds

van der Waals forces

intermolecular forces of attraction between the oppositely chargeed regions of nearby molecules

water

H2O; the greatest solvent on earth

oxygen end of the water molecule

slight negative charge because it pulls the electrons more

hydrogen end of the water molecule

slight positive charge because it has less attraction for the electrons

polar molecules

molecules in which the charges are unevenly distributed; they can attract each other

cohesion

attraction between molecules of the same substance

adhesion

attraction between molecules of different substances

mixture

material composed of two or more elements or compounds that are physically mixed together but not chemically combined

solution

a mixture in which all the components are evenly distributed throughout the mixture

solute

the substance in a solution that is dissolved

solvent

the substance in a solution in which the solvent dissolves

ions formed by water molecules

hydrogen ion (H+) and hydroxide ion (OH-)

suspensions

mixtures of water and nondissolved material

blood

a suspension of water, cells, and undissolved particles that moves through the body

pH 7

pH of pure water

pH scale

a measurement system to indicate the concentration of H+ ions in solution

acid

a compound that forms H+ ions in solution

pH above 7

bases

pH below 7

acids

base

a compound that produces OH- ions in solution

buffers

weak acids or bases that can react with strong acids or bases to prevent sharp, sudden changes in pH

organic chemistry

the study of all compounds that contain bonds between carbon atoms

organic compounds

carbon compounds

carbon's valence electrons

four

reasons carbon is important

can make covalent bonds with other atoms (4 valence electrons); can bond to other carbon atoms to make long chains

macromolecules

polymers; molecules made from thousands or even hundreds of thousands of smaller molecules

polymerization

a process that forms macromolecules by joining smaller compounds together to form larger ones

See More

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set