Living Environment Regents Review Practice Organization of Life Question 1
Monday, 29 June 2009 10:22
Which statement correctly describes one characteristic of the tube like digestive system of an earthworm?
A)The shape of the system allows food to be processed by intracellular digestion.
B)The shape of the system eliminates the need for egestion.
C)Various parts of the system perform different digestive functions.
D)Digestive enzymes are not used in the system.
Correct Answer: Option C - Various parts of the system performs different digestive functions.
The mouth is used for ingestion, the intestine for digestion, and the anus for egestion. Worms perform extracellular digestion because the food is digested outside of individual cells; food is digested within a tube. Enzymes are necessary for all chemical digestion.
Living Environment Regents Review Practice Organization of Life Question 3
Monday, 29 June 2009 10:19
The main function of the human digestive system is to
A)Rid the body of cellular waste materials
B)Process organic molecules
C)Break down glucose in order to release energy
D)Change amino acids into proteins and carbohydrates
Correct Answer: Option B - Process organic molecules
Digestion is the mechanical and chemical breaking down of food into smaller components, to a form that can be absorbed, for instance, by a blood stream. Digestion is a form of catabolism.
In mammals, food enters the mouth, being chewed by teeth, and broken down by the saliva from the salivary glands. Then it travels down the esophagus into the stomach. Acids break down most of the food. The "leftovers" go through the small intestine, through the large intestine, and are excreted during defecation.
Living Environment Regents Review Practice Organization of Life Question 4
Monday, 29 June 2009 10:17
What happens to certain nutrient molecules after they pass into muscle cells?
A)They are replicated in the nucleus.
B)They are changed into tissues and organs in the cytoplasm.
C)They enter chloroplasts, where they can absorb light energy.
D)They are acted on by enzymes and release the energy they contain.
Correct Answer: Option D - They are acted on by enzymes and release the energy they contain.
The majority of the time human cells employ aerobic respiration. Brief periods of oxygen depletion can happen during periods of vigorous exercise, when all the oxygen in the bloodstream is quickly used up by the muscle cells to meet the large energy demand. Without oxygen, human cells must find another way to convert glucose into ATP since stage D of aerobic respiration (The Electron Transport Chain) requires oxygen as a vital component. In this case, human cells shift briefly to a form of anaerobic respiration called lactate fermentation.
Living Environment Regents Review Practice Organization of Life Question 5
Monday, 29 June 2009 10:16
In humans, which of the following is produced within certain bones?
A)Red blood cells
B)Striated muscle cells
Correct Answer: Option A – Red blood cells
Red blood cells and some white blood cells are produced in the marrow of long bones in our bodies. Muscle cells attach to the outside of bone to allow locomotion. Bile and urea are both produced in the liver.
Skeletal muscle is a form of striated muscle tissue existing under control of the somatic nervous system. It is one of three major muscles found in biology, the others being cardiac and smooth muscle. As its name suggests, skeletal muscle is linked to bone by bundles of collagen fibers known as tendons.
Bile or gall is a bitter yellow, blue and green fluid secreted by hepatocytes from the liver of most vertebrates. In many species, bile is stored in the gallbladder between meals and upon eating is discharged into the duodenum where the bile aids the process of digestion of lipids.
The final nitrogenous excretion product of many organisms is urea. The chief solid component of mammalian urine; is synthesized from ammonia and carbon dioxide and used as fertilizer and in animal feed and plastics. The molecules are created from ammonia and carbon dioxide as a result of the urea cycle.
Living Environment Regents Review Practice Organization of Life Question 6
Monday, 29 June 2009 10:15
According to the heterotroph hypothesis, some early heterotrophs evolved into autotrophs because of their ability to synthesize organic compounds from water and
Correct Answer: Option C – Carbon dioxide
Heterotrophs must ingest, digest, and egest preformed organic matter. Autotrophs evolved from heterotrophs by developing a way to make their own organic food by changing water and carbon dioxide into glucose.
Living Environment Regents Review Practice Organization of Life Question 7
Monday, 29 June 2009 10:13
The presence of cilia, an oral groove, and food vacuoles, and the absence of chloroplasts in a unicellular organism indicate that the organism carries on
Correct Answer: Option D - Heterotrophic nutrition
Cilia are hair-like bristles on a Paramecium used in locomotion to find food. An oral groove is a mouth for a Paramecium, and food vacuoles store food in the cell body of the Paramecium. All of these are cell organelles used to ingest, digest, and egest preformed food, which is heterotrophic nutrition. An autotroph can make its' own food using chloroplasts.
Sexual reproduction is a mode of reproduction involving the fusion of female gamete (ovum) and male gamete (spermatozoon), which forms a zygote that potentially develops into genetically distinct offspring.
Autotrophic nutrition is a type of nutrition in which organisms synthesize the organic materials they require from inorganic sources. Chief sources of carbon and nitrogen are carbon dioxide and nitrates, respectively. All green plants are autotrophic and use light as a source of energy for the synthesis, i.e. they are photoautotrophic. Some bacteria are also photoautotrophic; others are chemoautotrophic, using energy derived from chemical processes.
Heterotrophic nutrition is a type of nutrition in which energy is derived from the intake and digestion of organic substances, normally plant or animal tissues. The breakdown products of digestion are used to synthesize the organic materials required by the organism. All animals obtain their food this way: they are heterotrophs.
Living Environment Regents Review Practice Organization of Life Question 8
Monday, 29 June 2009 10:12
Which statement regarding the functioning of the cell membrane of all organisms is not correct?
A)The cell membrane forms a boundary that separates the cellular contents from the outside environment.
B)The cell membrane is capable of receiving and recognizing chemical signals.
C)The cell membrane forms a barrier that keeps all substances that might harm the cell from entering the cell.
D)The cell membrane controls the movement of molecules into and out of the cell.
Correct Answer: Option C - The cell membrane forms a barrier that keeps all substances that might harm the cell from entering the cell.
It is a semipermeable lipid bilayer found in all cells.The cell membrane surrounds the cytoplasm of a cell and, in animal cells, physically separates the intracellular components from the extracellular environment, thereby serving a function similar to that of skin. In fungi, some bacteria, and plants, an additional cell wall forms the outermost boundary; however, the cell wall plays mostly a mechanical support role rather than a role as a selective boundary. The cell membrane also plays a role in anchoring the cytoskeleton to provide shape to the cell, and in attaching to the extracellular matrix to help group cells together in the formation of tissues. The barrier is selectively permeable and able to regulate what enters and exits the cell, thus facilitating the transport of materials needed for survival. The movement of substances across the membrane can be passive, occurring without the input of cellular energy, or active, requiring the cell to expend energy in moving it. The membrane also maintains the cell potential. The cell membrane cannot keep all substances that might harm the cell out. If that were true, then, as humans we would never get sick, never get poisoned, never get infected.
Living Environment Regents Review Practice Organization of Life Question 9
Monday, 29 June 2009 10:11
Which substances are secreted at the endings of nerve cells?
Correct Answer: Option C – Neurotransmitters
Neurotransmitters are chemicals that allow the impulse to travel across the synapse or gap between two neurons. Antibodies are produced by white blood cells to fight infection, antigens are marker proteins that distinguish self cells from non-self cells, and lipids are a group of organic compounds including fats, oils, and waxes.
Antibodies are gamma globulin proteins that are found in blood or other bodily fluids of vertebrates, and are used by the immune system to identify and neutralize foreign objects, such as bacteria and viruses.
An antigen is a substance that prompts the generation of antibodies and can cause an immune response
Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The main biological functions of lipids include energy storage, as structural components of cell membranes, and as important signaling molecules.
Living Environment Regents Review Practice Organization of Life Question 10
Monday, 29 June 2009 10:09
Which set of terms would most likely be used in a description of the nervous system of chordates?
A)Brain, fused ganglia, ventral nerve cord
B)Brain, dorsal nerve cord, highly developed receptors
C)No brain, fused ganglia, tympana
D)No brain, nerve net, modified neurons
Correct Answer: Option B - Brain, dorsal nerve cord, highly developed receptors
Chordates are a group of animals such as fish, frogs, snakes, birds, dogs, monkeys and humans. We all have central nervous systems made up of a brain and a dorsal (back) nerve cord. We all have highly developed receptors to detect changes in the environment for us to respond to. Fused ganglia are a primitive brain found in earthworms, tympana are primitive ears found in grasshoppers, and nerve nets are branched nerves without direction found in the hydra.
We are not affiliated with, nor endorsed by, the New York State Education Department.
The information contained in this website is for general information purposes only. The information is provided by "Technology Strategies for Success" and while we strive to keep the information up-to-date and correct, we make no representations or warranties of any kind, express or implied, about the completeness, accuracy, reliability, suitability or availability with respect to the website or the information, products, services, or related graphics contained on the website for any purpose. Any reliance you place on such information is therefore strictly at your own risk.