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In which way are vesicles different from vacuoles?
Vacuoles, like vesicles, are membranous sacs, but vacuoles are larger than vesicles and are often quite specialized. They are most often seen in plant cells.
When populations of different types of organisms interact in a given area, they comprise a(n)
Populations of different types of organisms interacting in a given area comprise a community.
The purpose of a control group in an experiment is
for comparison to the experimental group.
During an osmosis experiment in class, you look at some cells under the microscope. You notice the cells look crenated. What type of solution were the cells immersed in?
Water moves from an area of greater concentration of water to an area of lesser concentration of water. The cells are crenated because they lost water, which means the cells were immersed in a hypertonic solution.
When a positively charged hydrogen in a water molecule become attracted to the negatively charged oxygen in a nearby water molecule, this is referred to as a(n)
When a positively charged hydrogen in a water molecule become attracted to the negatively charged oxygen in a nearby water molecule, this is called a hydrogen bond.
what would happen to a cell Without gap junctions in certain tissues.....
Gap junctions allow adjacent cells to communicate.A gap junction lends strength to the cells, but it also allows small molecules and ions to pass between them. Gap junctions are important in heart muscle and smooth muscle because they permit the flow of ions that is required for the cells in these tissues to contract as a unit.
Humans store glucose in the form of
glycogen
Is the following statement true or false? All single-celled organisms are prokaryotes.
false, because some eukaryotes are single-celled
Which form of passive transport allows small noncharged molecules, such as oxygen, to cross the cell membrane?
In cells, simple diffusion may occur across a plasma membrane. Some small noncharged molecules, such as oxygen and carbon dioxide, are able to slip between the phospholipid molecules making up the plasma membrane.
A triglyceride is formed when three fatty acids join a glycerol by
When glycerol and three fatty acids join to form a triglyceride, three water molecules also form as a product. When two subunits are joined by the removal of a water molecule, this is known as a dehydration synthesis reaction.
Receptor proteins allow a cell to.....
bind to signal proteins from other parts of the body.
What makes saturated triglycerides less healthy than unsaturated ones?
Saturated fats tend to stick together in the blood forming plaque which could lead to the development of blockages in arteries
A(n)________ can be defined as a substance that keeps pH within established limits by taking up excessorin a solution.
buffer
Humans store glucose in the form of
glycogen.
What is the function of a peptide bond?
A peptide bond is a type of covalent bond that joins two amino acids together
There is an antibiotic called streptomycin that inhibits the function of bacterial ribosomes. Consequently, as the bacterial cells die, the person taking the antibiotics gets better. In other words, the antibiotic destroys bacteria by
Ribosomes function as the site of protein synthesis. The bacterial cells die when they are unable to produce necessary proteins
The hormone estrogen is________-based.
lipid
Which of the following property of water explains why a wet glass slide sticks to laboratory counter?
Water has four key properties that support life: solvency, cohesion/adhesion, surface tension, high heat capacity, and varying density. Adhesion occurs when a water molecule sticks to something other than another water molecule.
Autophagy is a process by which a cell breaks down and destroys old, damaged, or abnormal proteins and other substances in its cytoplasm. Autophagy is a function of which organelle?
Lysosomes are vesicles that contain digestive enzymes. In the case of autophagy, lysosomes use enzymes to break down and destroy old, damaged, or abnormal proteins and other substances within a cell.
A covalent bond occurs when
A covalent bond results when two atoms share electrons in order to complete their valence shell.
Salmon are born in fresh water but migrate out to marine waters for most of their life. Eventually, they return to the place they were born to spawn. Because migrating between fresh water and saltwater affects the balance of water in their body, salmon have evolved an internal control system called osmoregulation that restores water balance by negative feedback. This is an example of which characteristic of life?
Many of the metabolic activities of an organism are involved in maintaining homeostasis, or an internal environment that acts within a set of physiological boundaries. Since osmoregulation allows the salmon to maintain an internal water balance, this is an example of maintaining homeostasis.
A nucleotide is made up of ____________________________________
A nucleotide is comprised of a phosphate group, 5 carbon sugar, and nitrogenous base.
What prevents a plant cell from bursting in a hypotonic solution ?
When a plant cell is placed in a hypotonic solution, the vacuole gains water and the plasma membrane pushes against the cell wall. The plant cell does not burst because the cell wall does not give way.
What function do the carrier proteins embedded in the cell membrane serve?
Carrier proteins embedded in the cell membrane assist with facilitated diffusion
Amino acids are needed to build________, just as________ are needed to create DNA.
Amino acids are linked together to build proteins while nucleotides are linked together to build DNA.