Midterm Chumiecki
Which of the following conditions in required for simple diffusion to occur?
A concentration gradient
What is a hypothesis?
A tentative expplanation
In all organisms, substances are transported in and out of cells. What is required for the process of active but not for the process of passive transport?
ATP
Sodium ions are pumped from a region of lower concentration to a region of higher concentration in the nerve cells of humans. Which process does this represent?
Active transport
We observe that our hair grows and that our wounds heal. Which part of the cell theory represents this observation?
All cells come from preexisting cells
Why does the study of cell membranes lead to better understanding of cell function
All materials needed for cell functions must pass through the cell membrane
Which of the following statements is not a fundamental idea of the cell theory?
All organisms contain prokaryotic cells
From its atomic number 19, it is possible to predict that the potassium, atom has
B and c are correct
Which type of cell has genetic material that is housed in the nucleus?
Both plant and animal cells
What will happen to an animal cell placed in an extremely high salt water hypertonic solution?
Both processes require energy
A student in biology puts a sample of pond water on a slide and views it under a light microscope. The student observes a living, moving cell and draws a picture to represent what he saw. What eternal structures can be identified in the picture.
Cell wall and flagella
Which of the following sequences of organization is likely to be seen in a multicellular organisms, going from the smallest to largest?
Cell, tissue, organ, system
Cell theory was first proposed in 1838. Evidence obtained through additional scientific investigations resulted in the current cell theory. Which statement describes a component of the original cell theory that was removed because of the new scientific knowledge?
Cells form through spontaneous generation.
At a cooking demonstration, the speaker's grand finale was sautéing mealworm (insect larvae) in butter and serving them to the audience. They were crunchy (like popcorn hulls) because their exoskeletons contain the polysaccharide?
Celulose
The digram below shows a drawing of a cell. Which is not pictured in the drawing.
Central vacuole
Which organelle is associated with photosynthesis
Chloroplast
What is the function of a selectively permeable membrane?
Controls what enters and leaves the cell.
What is the name of the semi-fluid environment inside the plasma membrane called?
Cytoplasm
Which of the following statements best summarizes the structural differences between DNA and RNA
DNA nucleotides contain a different sugar than RNA nucleotides.
The ___ variable is measured or observed during a scientific experiment
Dependent
What is the primary difference between diffusion and osmosis?
Diffusion is the movement of any substance from high to low concentration, while osmosis is the movement of water from high to low concentration.
Lactose, a sugar in milk, is composed of a glucose molecule bonded to a galactose molecule. How is lactose classified?
Disaccharide
Which of the following is NOT a type of passive transport?
Endocytosis
Which protein is mismatched to its function
Enzymes - transport oxyen
Which of the following statements regarding enzymes is true?
Enzymes speed up chemical reactions reaction by lowering the activation energy.
Molecules that are too large to be moved across the membrane can be removed from the cell by which process?
Exocytosis
Phospholipid molecules in a mewmbrane are arranged with their ____ on the exterior and their ____ on the interior.
Hydrophillic heads; hydrophobic tails
Explain why ice floats on water.
Ice floats on water because ice has a lower density then water so ice doesn't break water's hydrogen bonds.
What is the role of ATP in the process of active transport
It provides the energy that cells need to move molecules against a concentration gradient.
Different types of biological macromolecules interact at the cell membrane. Some of these interactions are illustrated in the diagram below. Which statement accurately describes the interrelated of three types of macromolecules at the cell membrane.
Lipids make up the membrane, proteins form channels in the membrane, and certain carbohydrates pass through the channels to move in and out of the cell.
Which structure is usually present only in animal cells?
Lysosome
Which organelle digests worn-out organelles or food particles
Lysosomes
The SI unit of measure for length is
Meters
Which organelle is most responsible for ATP production
Mitochondria
Which of the following organelles is correctly matched with the molecule that it produces
Mitochondrion - ATP
Which of these is a hypothesis?
My car's battery is dead.
Where is a cell's genetic material contained
Nucleus
THe process by which water passes into or out of the cell is called?
Osmosis
What are three characteristics of mitochondria and chloroplasts that suggest that they might have evolved from free living prokaryotes in distant past?
Own membrane, Own DNA, Reproduction
The type of bond that forms between amino acid monomers joining them into proteins?
Peptide
What do all cells have in common
Plasma membrane
Which of the following cell parts have similar or related jobs?
Plasma membrane and nuclear membrane
Bacteria are what type of cell?
Prokaryotic
1802, Hans Bauer identified an additional envelope in the interior of some cells., He proposed two categories of cells: those which contained this "nuclear enveloped" and those did not. In hindsight, what types of cells were being distinguished b Bauer's categorization
Prokaryotic and eukaryotic cells
While studying the planet Mars, a. NASA scientist discov ers some living cells. She notices that each cell lacks a nucleus, but contains ribosomes, and has a cell membrane. What type of cell should she suspect she discovered.
Prokaryotic cell
Most cell membranes are composed principally of what two substances?
Proteins and lipids
According to the pH values in the table 9, the solution which has as many hydrogen ions (H+) as hydroxide ions (OH-) and is neutral is
Pure water
What is the main function of a selectively permeable cell membrane?
Regulates what enters and leaves the cell
Which of the following is a characteristic of life
Respond to stimuli
The Rough ER is so named because it has an abundance of
Ribosomes
The cell membrane of red blood cell will allow water, oxygen, and carbon doxide to pass through. Because other substances are b locked from entering the cell, what is the cell membrane considered
Semi-permeable
The nucleus of a calcium atom contains 20 neutrons and 20 protons. Which of the following is a correct statement?
The calcium atom has a mass number of approximately 40 and an atomic number of 20
What does the flow of water molecules in and out of the cell depend on?
The concentration of water molecules inside and outside of the cell
An investigation was set up to study the movement of water through a membrane. The results are shown in the diagram below, Based on these results,m which placed in a beaker containing a water solution in which the salt concentration is much higher than the salt concentration in the red blood cells.
The red blood cells will lose water and decrease in size
What is Biology
The study of life
A person with swollen gums rinses his mouth with warm salt water and the swelling decreases. Which of the following has occurred?
The water in the gums has moved out due to the high concentration of salt in the solution.
How do hypotheses differ from theories?
Theories are a set of hypothesis supported by a great deal of scientific data
MAny scientists think that mitochondria in eukaryotic cells originated as indepentent prokaryotes. Which characteristic of mitochondria most strongly supports this conclusion
They lack membrane-bound organelles but include their own DNA
In active transport, carrier proteins carry out which function?
They move substances from a low concentration to high concentration with the use of ATP
What moves much needed substances or waste materials through the plasma membrane?
Transport proteins
AN analogy often used to describe a eukaryotic cell is that of a city, with the cell membrane acting as "city walls" the mitochondria as power plants, and so on. Which of these analogies describing other eukaryotic cell structures is accurate
Vacuole - grocery store
What will most likely occur when a cell is placed into saline solution that has a lower salt concentration than inside the cell?
Water molecules will move until the salt concentration is the same both inside and outside the cell.
State the hypothesis that you think the above experiment may have been designed to test.
With more fertilizer the plant will grow more leaves.
A substance that moves across the cell membrane without using the cell's energy tends to move
away from the area where it is more concentrated
What is a the smallest biological unit
cell
Animals have skeletons to provide and plants do not? Where do plants get their structural support from?
cell wall — made up of cellulose
What are the basic units of life
cells
Which of the following structures would be present in a plant cell, but not in an animal cell?
chloroplasts, cell wall, central vacuole
Which of the following is NOT found in the nucleus?
cytoplasm
There are 20 different amino acids. What makes one amino acid different from another?
different side chains (R groups) attached to central carbon
Which of the following are storage polysaccharides?
glycogen and starch
Some animals use large amounts of energy while performing normal activities. What organelles do these animals most likely have large numbers of in their muscle cells.
mitochondria
Which of the following are the proper components of the scientific method?
observation, question, hypothesis, prediction, experiment, results, conclusion
Glucose is not able to pass through a semi-permeable cell membrane. If the cells need sugar to make ATP and carry out cellular processes, how does the sugar get into the cell?
passive transport by facilitated diffusion
Which structures below contains polar and non-polar ends and forms the plasma membrane?
phospholipid bilayer
Which of the following is not a function of Golgi apparatus?
produces proteins
There are some similarities between prokaryotic and eukaryotic cells. Which of the following structures is found in both prokaryotic and eukaryotic cells?
ribosome
Which cell structure is correctly paired with its primary function?
ribosome - protein synthesis
In a scientific experiment, the control group
serves as a basis of comparison with the experimental group
What does adaptation mean in a biological context
the accumulation of favorable variations in a population over time