Bio Exam 1
Diffusion
the movement of substances from an area of higher concentration to an area of lower concentration
Hydrophilic
water loving. substances that easily mix with water.
Nitrogen has 7 protons, 7 neutrons, and 7 electrons. What is the atomic mass of nitrogen?
14
Oxygen has 8 protons, 8 neutrons, and 8 electrons. What is its atomic number?
8
Bases
Accept H+
Sodium ions will most efficiently be moved from the right of the membrane to the left side using
Active transport
After adding a small amount of solution A to solution B, the pH of solution B declines from 8 to 3. Solution A must contain
An acid
Carbon's prominence in living systems can be explained by the fact that
Carbon-based molecules can form long chains and rings
Solution
Combination of solute and solvent
In the White Nose Bat scenario, when the researchers compared bats that either been injected with the toxin or "sham injected" with no toxin. The group of 18 that were "sham injected represent a _________ group that experienced ________
Control; no change in the independent variable
In the chemical reaction forms hydrogen peroxide (H202), hydrogen and oxygen share electrons, creating ___________ bonds between the two atoms
Covalent
Simple diffusion
Direct diffusion through a membrane; no energy required, no transport proteins needed
Solute
Dissolved substance (particles)
Acids
Donate H+
An acid is a polar substance that dissolves in water and
Donates hydrogen ions to the solution
A white blood cell (WBC) encounters bacteria in a scrape on the knee of a child who has fallen off on his bicycle. The WBC's job is to take the bacteria inside of itself and destroy the bacteria. How will the WBC most likely ingest the bacteria
Endocytosis
Active transport
Energy-requiring process that moves material across a cell membrane against a concentration difference
Which of the following is part of accepted cell theory?
Every living organism is composed of one or more cells, and all living cells arise from preexisting cells
Exocytosis
Exporting substances from a cell
Sodium ions will most efficiently be moved from the left side of the membrane to the right side using
Facilitated diffusion
Hypertonic
Having a higher concentration of solute
Hypertonic
Having a lower concentration of solute
Phospholipids are large organic molecules with a hydrophilic, polar phosphate head connected to hydrophobic, nonpolar fatty acid tails. These molecules arrange themselves to form a mostly impermeable barrier between a liposome and its environment by lining up
Hydrophobic tails facing each other at the center line of the membrane with the hydrophilic heads facing outward, away from the center line of the membrane
Endocytosis
Importing substances into a cell
Dialysis tubing is a selectively permeable membrane that can be filled with a solution to simulate a cell. A piece of dialysis tubing has been filled with a cloudy white solution of 5 percent starch, 5 percent egg albumin (protein), and 5 percent glucose (sugar) dissolved in water to simulate a cell. This simulated cell. is once again weighed. Over time, the weight of the simulated cell can be expected to:
Increased because the solution in the beaker is hypotonic to the simulated cell and water will enter the simulated cell through osmosis
A car wash attendant offers to treat Martian's windshield with a protective chemical. This substance coats the glass and excludes water, causing beads of the water to easily roll off during a rain shower. Which of the following must be correct about the protective system?
It must be hydrophobic and non polar
A scientific hypothesis must be constructed with which of the following characteristics?
It provides a reasonable explanation to a question and is consistent with current observations; it must also be testable and falsifiable
If the concentration of sugar molecules in water on side "A" of a selectively permeable membrane is 5 percent, and the concentration of sugar molecules in water on side "B" of a selectively permeable membrane is 15 percent, the water will
Mostly move from side "A" to side "B" because the sugar concentration is higher on side "B"
Facilitated diffusion
No-energy; Diffusion through a membrane that requires transport proteins
Which of the molecules are the most hydrophilic
Non-polar molecules are not hydrophilic, Only polar and charged ions.
A scientist observed a chemical that changes to bright red in the presence of organic compounds containing nitrogen and phosphorus. To test this chemical, a set of test tubes each containing a purified sample of one of the following organic compounds is prepared. The chemical is then added to each tube. The test tube containing ________ will always turn bright red.
Nucleic acids
________ is the process where the solvent water diffuse across a semipermeable membrane from an area where water is more concentrated to an area where water is less concentrated (choose the most correct answer.)
Osmosis
Passive transport
Requires NO energy, Movement of molecules from high to low concentration, Moves with the concentration gradient
Isotonic
Same concentration inside and outside the cell
You are reading an article in the National Geographic regarding the evolution of humans. This would be an example of _______ literature.
Secondary
When scientists generate a single informed, logical, and plausible explanation for a question and observations of the natural world, they are proposing a scientific
Theory
Thomas's foot began to swell after he was stung by a scorpion. Thomas's friend said his mom had an old, trusted herbal poultice remedy that would absorb the venom from the foot, reduce the swelling, and heal the foot. Thomas allowed his friend to place the herbal poultice on his foot before going to bed that night. and the swelling was gone in the morning. Which of the following can be conducted about the herbal poultice remedy.
There is not anything that can be concluded about the effectiveness of the poultice remedy.
Which of the following accurately describes viruses?
Typically a piece of genetic material encased in proteins, viruses are small, noncellular infectious agents that are only capable of reproducing when inside a living cell such as those of plants, animals, fungi, protozoans, or bacteria.
Hydrogen bonds
Very weak bonds; occurs when a hydrogen atom in one molecule is attracted to the electrostatic atom in another molecule
Hydrophobic
Water fearing; A substance that does not dissolve in water