76 terms

God bless Lucy Sundrop - Biology things

Describe the role of energy in chemical reactions.
Some chemical reactions release energy, and other chemical reactions absorb energy. Energy changes determine how easily a chemical reaction will occur
What are enzymes, and how are they important to living things?
Enzymes are biological catalysts. Living cells use enzymes to speed up virtually every important chemical reaction that takes place in cells.
Describe how enzymes work, including the role of enzyme-substrate complex.
Substrates, the reactants of an enzyme-substrate complex, attach to the enzyme at an active site and form an enzyme-substrate complex. Once the complex is formed, the enzyme helps convert substrate into product
A change in pH can change the shape of a protein. How might a change in pH affect the function of an enzyme such as hexokinase?
A change in pH could change the shape of hexokinase. This change would diminish or possibly eliminate the ability of glucose and ATP to bind to the active site on the enzyme
Name four groups of organic compounds found in living things.
Carbohydrates, lipids, nucleic acids, and proteins
Describe at least one function of each group of organic compounds
Living things use carbohydrates as their main source of energy, fats can be used to store energy, nucleic acids transmit hereditary information, and proteins from tissues
What proteins of carbon explain carbon's ability to form many different macromolecules
Each carbon atom can form four covalent bonds, and carbon atoms can bond with other carbon atoms
Explain why proteins are considered polymers but lipids are not
Proteins are made up of amino acid monomers joined in long chains. Although fatty acid chains may be mistake for monomers, only three fatty acids can attach to a glycerol molecule
Compare the structures and functions of the biomolecules lipids and starches
Lipids are made mostly from carbon and hydrogen atoms; starch is a carbohydrate made up of carbon, hydrogen, and oxygen atoms. Both can be used to store energy
Prokaryotic Cell
Have genetic material that is not contained in a nucleus; simple cell
Prokaryotic cells have this; the portion of the cell forming the soup. It has no nucleus
Cell Wall
Prokaryotic cells are surrounded by a ______, which supports the cell in a rigid fashion
Cell Membrane
This is the thin, flexible layer around the cell, which regulates what enters and leaves the cell
Eukaryotic Cell
This cell contains a nucleus
This contains the genetic material and controls the cell's activities
The dense region of the nucleus where ribosomes are assembled
Chromatin, or genetic material, is organized at times into ________
Eukaryotic cells have ______, whereas prokaryotes don't
Proteins are made on ______
Endoplasmic Reticulum
Highway of cell to transport biochemicals like fat and protein. Rough: has proteins. Smooth: Does not
Golgi Apparatus
Package proteins and other molecules for storage/movement
Sac of enzymes to digest
Storage sac for water, salt, or other biochemical substances
Powerhouse of cell, converting chemicals into energy
Only in plants for photosynthesis, turns light into sugar
Structure for support and used to transport matter within the cell. It can be associated with the movement of chromosomes during mitosis and meiosis
Threadlike structures made of the protein called actin useful to help move the cells around, such as an ameba
Made of protein tubulin, these structures are also used in cellular movement
Microtubule used for cell division
Describe the structure of an atom.
Atoms have a nucleus made up of protons and neutrons. Electrons are in constant motion in the space around the nucleus
Why do all isotopes of an element have the same chemical properties? In what way do isotopes of an element differ?
They have the same number of electrons. They differ in number of neutrons
What is a covalent bond? An ionic bond?
A covalent bond forms when electrons are shared between atoms. An ionic bond forms when electrons are transferred
What is a compound? How are compounds related to molecules?
A compound is a substance formed by the chemical combination of two or more elements in definite proportions. A molecule is the smallest unit of most compounds
How do van der Waals forces hold molecules together?
When the sharing of electrons in unequal, a molecule has regions that are changed. An attraction can occur between the oppositely charged regions of nearby molecules.
How are ionic bonds and van der Waals forces similar? How are they different?
In both cases, particles are held together by attractions between opposite charges, but the attractions are stronger between the ions than they are between the molecules
Checks and Balances
System of overlapping the powers of the legislative, executive, and judicial branches to permit each branch to check the actions of the others
A separate clause or paragraph of a legal document or agreement, typically one outlining a single rule or regulation
Numbered sections of the constitution
Rule of Law
Concept that Government and its officers are always subject to the law
Rule of Law
Government is not above the law
Executive Agreement
A pact made by the president directly with the head of a foreign state
Executive Agreement
A binding international agreement with the force of law but which (unlike a treaty) does not require Senate consent
Bill of Rights
The first 10 amendments to the Constitution
Bill of Rights
Brought in immediately
Basic principle that government and those who govern must obey the law; the rule of law
Government must be conducted according to the constitution
Formal Amendment
Change or addition that becomes part of the written language of the constitution itself through one or four methods set forth in the constitution
Judicial Review
The power of a court to determine the constitutionality of a governmental action; executive or legislature
Contrary to constitutional provision and so illegal, null and void, of no force and effect
Against the constitution
A change in, or addition to, a constitution or law
What three statements make up the cell theory?
•All living things are composed of cells
•Cells are the basic units of structure and function in living things
•New cells are produced from existing cells
What are the differences between prokaryotic cells and eukaryotic cells?
Prokaryotic cells have genetic material that is not contained in a nucleus, whereas eukaryotic cells have a nucleus that houses the genetic material
Compare the processes used to produce a TEM and a SEM.
They both must use slides that have nonliving, preserved cells and tissues that are examined in a vacuum sealed slide. On the other hand, for the TEM to work well, the cell or tissue sample must be sliced into ultra thin samples, which is not needed for the SEM
What structures do all cells have?
All cells have two structures in common: a barrier called a cell membrane and a molecule that carries biological information called DNA
How did the invention of the microscope help the development of the cell theory
The microscope allowed scientists to examine cells that could not be seen by the naked eye. Once scientists could examine cells with a microscope, they could support the concept that matter was made of cells
Use the structure of a water molecule to explain why it is polar.
The hydrogen atoms form covalent bonds with the oxygen atom. Because of oxygen's greater attraction for electrons, there is an unequal distribution of electrons. The oxygen end of the bent water molecule is negative, the hydrogen end is positive.
Compare acidic and basic solutions in terms of H+ and OH- ion concentrations.
Per volume, there are more H+ ions than OH- ions in an acidic solution and more OH- ions than H+ ions in a basic solution
What is the difference between a solution and a suspension?
In a solution, all components are evenly distributed. In a suspension, undissolved particles are suspended in the mixture and can settle out over time
What does pH measure?
The pH scale measures the concentration of H+ ions in a solution
The strong acid hydrogen fluoride (HF) can be dissolved in pure water. Will the pH of the solution be greater or less than 7?
The pH will be less that 7.0
Summarize the light-dependent reactions.
The light-dependent reactions produce oxygen gas and convert ADP and NADP into the energy carriers ATP and NADPH
What reactions make up the Calvin cycle?
The Calvin cycle uses ATP and NADPH from the light-dependent reactions to produce high-energy sugars
How is light energy converted into chemical energy during photosynthesis?
Light energy is converted into chemical energy by the pigments in the chloroplast
What is the function of NADPH?
The main function of NADPH is to carry high-energy electrons produced by light absorption in chlorophyll to chemical reactions elsewhere in the cell
Why are the light-dependent reactions important to the Calvin cycle?
The light-dependent reactions provide the Calvin cycle with ATP and NADPH. The Calvin cycle uses the energy in ATP and NADPH to produce high-energy sugars.
What is the ultimate source of energy for plants?
The sun
What is ATP and what is its role in the cell?
Stands for adenosine triphosphate, which is one of the principal chemical compounds that living things use to store energy and release it for cell work to be done
Describe one cellular activity that uses the energy released by ATP.
Active Transport. Many cell membranes contain a sodium-potassium pump, a membrane protein that pumps sodium ions out of the cell and potassium ions into it. ATP provides the energy that keeps this pump working, maintaining a carefully regulated balance of ions on both sides of the cell membrane.
How do autotrophs obtain energy? How do heterotrophs obtain energy?
Autotrophs obtain energy by making their own food. Heterotrophs obtain energy from the food they consume.
With respect to energy, how are ATP and glucose similar? How are they different?
Both store chemical energy for a cell. A single molecule of glucose stores more than 90 times the chemical energy of an ATP molecule.
What did van Helmont, Priestley, and Ingenhousz discover about plants?
Van Helmont discovered that water was involved in increasing the mass of a plant. Priestley discovered that a plant produces the substance in air required for burning. Ingenhousz discovered that light is necessary for plants to produce oxygen.
Describe the process of photosynthesis, including the reactants and products.
Photosynthesis uses the energy of sunlight to convert water and carbon dioxide into oxygen and high-energy sugars.
Why are light and chlorophyll needed for photosynthesis?
Light provides the energy needed to produce high-energy sugars. Chlorophyll absorbs light, and the energy of that absorbed light makes photosynthesis work.
Describe the relationship between chlorophyll and the color of plants.
Plants are green because green light is reflected by the chlorophyll in leaves.
How well would a plant grow under pure yellow light? Explain your answer.
The plant would not grow well because chlorophyll does not absorb much light in the yellow region of visible light.