Chapters 4 and 5 Flashcards
You look into an electron microscope and view an unknown cell. What might you see that would tell you whether the cell is prokaryotic or eukaryotic?
mitochondria
Which one of the following is the major structural component of the cell membrane?
phospholipid
Prokaryotic cells use flagella for
propulsion
Which of the following is a function of the plasma membrane?
regulate the traffic of chemicals into and out of the cell
When mixed with water, phospholipids spontaneously form membranes because they
have hydrophilic phosphate groups that are attracted to water and hydrophobic fatty acids that avoid water
The liver is involved in detoxification of many poisons and drugs. Which of the following structures is primarily involved in the process and therefore abundant in liver cells?
smooth ER
What structures move proteins from the ER to the Golgi apparatus?
transport vesicles
Some ribosomes are suspended in the cytosol of a cell, whereas other ribosomes
are attached to the rough endoplasmic reticulum
Which of the following would be a characteristic of mitochondria that suggests that they might have evolved from free-living bacteria?
the mitochondria have their own DNA
An object at rest has no…. energy, but it may have…. energy resulting from its location or structure.
kinetic; potential
If the human body is 34% efficient, 66% of the food energy is converted to
heat
ATP has a large amount of potential energy because of
the crowding of the (three) negatively charged phosphate ions
Glucose molecules provide energy to power the swimming motion of sperm. In this example, the sperm are changing…
chemical energy into kinetic energy
Diffusion is an example of
passive transport
Facilitated diffusion across a biological membrane requires… and moves a substance..
transport proteins… without ATP
Osmosis can be defined as…
the diffusion of water
Enzymes are …. molecules which… specific chemical reactions.
protein…speed-up
Active transport….
can move solutes from a lower concentration to a higher concentration
Substances that plug up an enzyme’s active site are…
enzyme inhibitors
What are enzymes?
Enzymes are proteins that catalyze chemical reactions.
Why are enzymes important in the human body?
they are important because they speed up necessary reactions in the body so that we get the products that we need from those reactions at a fast enough rate, so we can actually use those products.
What does the lactase enzyme have to do with lactose intolerance?
The lactase enzyme catalyzes the reaction between lactose and water, helping us digest lactose. If the lactase enzyme is not present of if there are not enough of them, lactose will go through the digestive tract without being digested. As a result, your body releases hydrogen and acids that cause discomfort whenever you eat lactose, causing lactose intolerance.
What is the purpose of the glucose strips? What does the glucose concentration tell you?
The glucose test strips help us understand which sample is which by making us aware of the presence or absence of glucose in each milk sample. This also helps us determine the effect of latex on each milk sample.
What effect does Lactex (Lactase Enzyme Solution) have on cow milk?
Lactex helps catalyze the reaction that breaks down the lactose in milk into glucose and galactose.
