biology Exam 2
As a molecule moves through the plasma membrane it passes through
a hydrophilic layer of phospholipid heads, then a hydrophobic layer of phospholipid tails, and then another hydrophilic layer of phospholipid heads.
The part of the enzyme into which the substrate fits is called the ______
active site
Which of the following organisms can perform photosynthesis?
algae
Which of the following is an example of potential energy rather than kinetic energy?
an apple made up of energy-rich macromolecules
In photosynthesis, the light reactions ________ while the Calvin cycle ________.
capture solar energy; converts the captured energy to chemical potential energy
As climate change leads to drier and drier summers in the southeastern United States, more and more homeowners find that they have crabgrass growing in their yards. The reason for this is that
crabgrass is a type of C4 plant that does well in dry climates.
Which form of passive transport allows small noncharged molecules, such as oxygen, to cross the cell membrane?
diffusion
Which of the following terms best describes entropy?
disorder
Simple diffusion across a plasma membrane is called passive transport because it
does not require energy from the cell
Which of the following reactions builds sugars rather than breaks them down?
Calvin cycle
The main structural component of a plant cell wall is
Cellulose
It converts light energy into chemical energy.
Cholorplast
If the concentration of the solute is the same in the cell as it is in the surrounding solution, the cell is in a(n) _________________
Correct match: isotonic solution
What process typically regulates the enzymes involved in metabolic reactions?
feedback inhibition
Synthesis and transports of lipids
Smooth endoplasmic reticulum
The light reactions produce ________, which are used in the Calvin cycle. The Calvin cycle releases ________, which return to the light reactions.
ATP and NADPH; ADP and NADP
#1 What is the name of this organelle? #2 An individual sac in which the light reactions of photosynthesis takes place #3 A fluid in the chloroplast containing dissolved enzymes & starch granules #4 Stacks of thylakoids
1. Chloroplast 2.Thylakoid 3.Stroma 4.Grana
#1 Group of cells that are provided with a large number of chloroplast #2 Transports water, minerals, and food through the leaf #3 Small pores that open and close for exchange of gases
1. Mesophyll 2. Leaf Vein 3. Stoma or Stomata
How many turns of the Calvin cycle would be required for a plant to make one molecule of glucose?
6
Both plants and animals need mitochondria to produce
ATP
*filled with cytoplasm *plasma membrane *chromosomes
Both Prokaryotic and Eukaryotic
*plant and animal cells *membrane-bound nucleus *contains many specialized organelles
Eukaryotic
Modifies the contents within vesicles and then repackages them for export
Golgi apparatus
Which of the following statements describes the function of a chloroplast?
It converts light energy into chemical energy
Site of cellular digestion such as breaking down excess or worn-out cell parts
Lysosomes
Protein synthesis
Ribosomes
The second law of thermodynamics states that all energy transformations result in an increase in entropy (disorder). If so, how does photosynthesis, which is an energy transformation, create order rather than disorder?
The tree takes in small disordered molecules like carbon dioxide from the air and water from the earth and using solar energy produce highly ordered sugar molecules like glucose.
A plant that uses CAM photosynthesis is most likely to be successful in what type of environment?
hot, dry
If blood cells are placed in a solution and noticbly shrink due to water loss, they are in a(an)
hypertonic solution
During an osmosis experiment, you place some plant cells under the microscope. You notice the cells seem very swollen. What type of solution were the cells immersed in?
hypotonic solution
Where within the cell is the majority of ATP produced?
mitochondria
CAM photosynthesis limits CO2 fixation to nighttime hours in order to
open stomata only at night, limiting water loss because of heat and low humidity.
Since the plasma membrane blocks the passage of all but a few molecules with specific traits, it is necessary for other molecules to
pass through the membrane via proteins.
Which feature is found in all cells?
plasma membrane composed of phospholipids
Which of the following correctly lists the order in which energy flows through an ecosystem?
solar energy - chloroplast - mitochondria
Why do metabolic pathways require tens to hundreds of different enzymes?
Each enzyme has a specific substrate and produces a specific product.
Produces ATP
Mitochondria
There is an antibiotic called streptomycin that inhabits the function the function of bacteria and ribosomes. Consequently, as the bacteria cells die, the person taking the antibiotics gets better. In other words, the antibiotic destroys bacteria by...
Not allowing them to produced proteins.
Which of the following structures would NOT be found in a prokaryotic cell?
Nucleus
What process allows water to move across a cell membrane?
Osmosis
Which of the types of cellular activities listed below can proceed without ATP energy?
Passive transport
A white blood cell surrounds and engulfs a worn-out red blood cell.
Phagocytosis
What must materials pass through to enter or leave a cell?
Plasma Membrane
*bacteria *comparatively small *lack a membrane bound nucleus
Prokaryotic
A tube with a membrane covering the bottom is placed in a beaker. The membrane allows water to flow through but not salt or glucose. If the tube contains an aqueous solution with 4% salt and 20% glucose and the beaker contains an aqueous solution with 12% salt and 6% glucose, what would happen to the level of the water in the tube?
The level of the solution in the tube would rise because there are more dissolved solutes in the tube than the beaker.
Why do plants contain other pigments besides chlorophyll?
The additional pigments are able to absorb other light wavelengths that chlorophyll cannot.
