HESI A2 BIOLOGY (Definitions, Questions and Answers) 100% Correct.
In the hierarchic system of classification, which of the following is the least
... [Show More] inclusive?
Species
After observing an event, you develop an explanation. This statement is referred to as which of the following?
Hypothesis
A molecule of water is bonded with another molecule of water by what type of bond?
Hydrogen
Which of the following is a benefit of the intermolecular hydrogn bonding of water?
Water has a relatively high specific heat value
Water has strong cohesive and adhesive properties
Polarity of water allows it to act as a versatile solvent
Of all the molecules that are significant to biology, which of the following are considered the most important?
Carbohydrates, lipids, protein, and nucleic acids
Lipids are better known as fats, but what are they specifically?
Fatty acids
Phospholipids
Steroids
What are the two categories of fatty acids?
Saturated fats and unsaturated fats
How do phospholipids function in cells?
They are integral components of the plasma membrane
Which of the biologic molecules are considered the most significant contributor to cellular function?
Proteins
Proteins are polymers of which of the following?
Amino acids
Which of the following proteins catalyze different reactions or processes?
Enzyme
Which of the biologic molecules are components of the molecules of inheritance?
Nucleic acids
What is the sum of all chemical reactions that occur in an organism?
Metabolism
In a cell, reactions take place in a series of steps called:
Metabolic pathways
What is the fundamental unit of biology?
Cell
Which type of cell contains no defined nucleus?
Prokaryotic cell
What is the primary purpose of the flagella on the surface of cells?
Movement of the cell
Which cell organelle functions to transport materials from the endoplasmic reticulum throughout the cell?
Golgi apparatus
Which of the following are the distinct organelles that produce cell energy?
Mitochondrion and chloroplast
Which component of the cell contributes to the protection, communication, and passage of substances into and out of the cell?
Cell membrane
The cell membrane consists of a bilayer of phospholipids with proteins, cholesterol, and glycoproteins. This bilayer creates a hydrophobic region between two layers of lipids, making it which of the following?
Selectively permeable
What are the two catabolic pathways that lead to cellular energy production?
Fermentation and cellular respiration
What is the first step in the conversion of glucose to pyruvate?
Glycolysis
Which step in cellular respiration yields the greatest amount of ATP?
Electron Transport Chain
During cell respiration, the conversion of glucose results in an overall production of how many ATP molecules?
32-36
What is the function of water in photosynthesis?
Supply electrons in the light reactions
Cells reproduce by different processes, all of which fall into what two categories?
Sexual reproduction and asexual reproduction
Which of the following describes how a bacterium reproduces?
Binary fission
Regarding mitosis and cytokinesis, one difference between higher plants and animals is that in plants:
A cell plate begins to form at telophase, whereas in animals a cleavage
furrow is initiated at that stage
During which phase of cell reproduction does the cell divide forming two separate identical cells?
Cytokinesis
How does meiosis differ from mitosis?
In meiosis, each of the daughter cells contains half as many
chromosomes as the parent
At which phase of meiosis does crossing over occur?
Prophase 1
A cell division occurs in a human. The resulting cells contain 23 chromosomes. This is a description of gametes formed by which process?
Meiosis
If you wanted to determine the probability of a genotype, which of the following would you use?
Punnett square
Which of the following terms is used to describe the appearance of the organism?
Phenotype
What is the probability that a recessive trait would be expressed in offspring if two parents who are both heterozygous for the desired trait were crossed?
25%
Because genetics is the study of heredity, many human disorders can be determined by studying a person's chromosomes or by creating which of the following?
Pedigree
Why is DNA important for metabolic activities of the cell?
It controls the synthesis of enzymes
During protein synthesis, what process uses an RNA strand to produce a complementary strand of DNA?
Transcription
During the process of transcription, a sequence of RNA is generated in which the RNA base cytosine (C) is inserted complementary to the DNA base guanine (G). Which RNA base is inserted complementary to the DNA base thymine (T)?
Adenine
Why is polarity the most important characteristic of water?
The results of the polarity are hydrogen bonding, a high specific heat
value, and its versatile solvent properties.
Athletes are often concerned with the question of what they need in their diets to increase muscle mass and strength. What biological molecule would you recommend that would accomplish this?
Proteins
Which organelle would you expect to be present in a cell responsible for detoxifying multiple molecules?
Smooth ER (endoplasmic reticulum)
A cell from heart muscle would more than likely contain an unusual high proportion of:
Mitochondria
Which part of cellular respiration produces the greatest amount of ATP?
Electron Transport Chain
When plants do not receive enough water their photosynthetic rated drops. This is because:
Water is a raw material for the light reactions in photosynthesis
Which of the following statements is true about the Krebs cycle and the Calvin cycle?
Both result in a net production of ATP and NADH
Why is it important for cells to undergo mitosis?
Mitosis produces cells for growth and repair of body tissue
72 Chromosomes undergo meiosis. How many chromosomes will be in each gamete?
36
Which of the following shows how information is transformed to make a protein?
DNA-RNA-protein
What is the typical result of mitosis in humans?
two diploid cells
How does water affect the temperate of a living thing
Water keeps temperature stable
What are the products to kreb cycle?
Carbon dioxide, ATP, and energy carriers
What kind of none connects sugar and phosphate in DNA
Covalent bonds
What is the second part of an organism;s scientific name?
Species
How are lipids different that other organic molecules?
They are not water soluble
What is a cohesive property?
Water is attracted to water
What is adhesive property?
Water is attracted to other substance
Which hormone is produced by the pineal gland?
Melatonin
What is the name of the organelle that organizes protein synthesis?
Ribosome
During which phase is the chromosome number reduced from diploid to haploid
Meiosis I
What is the name for a cell that does not contain a nucleus?
Prokaryote
What is the name of the physical presentation of an organism's genes?
Phenotype
Which of the following forms of water is the densest?
Liquid
What is the longest phase in the life of a cell?
Interphase
What is not found in bacterial cell?
Mitochondria
What kind of macromolecule is hemoglobin?
Proteins
Which of the following is not involved in translation? RNA, mRNA, ribosome, DNA
DNA
Which of the following is necessary for cell diffusion
Water
How many different types of nucleotides are there in DNA?
4 (cytosine, guanine, adenine, thyamine)
Which of the following cell types has no nucleus
Red blood cells
Which part of the aerobic respiration uses oxygen?
Electron transport chain
What is the most general taxonomic category?
Kingdom
What is the name of the process by which a bacterial cell splits into two new cells?
Binary fission
Name the taxonomical classification of living things, in order of increasing specificity.
Kingdom, phylum, class, order, family, genus, species
Name the 5 biological kingdom
monera, protista, fungi, plantae, animalia
Name the hierarchal levels of life from simplest to more complex
Atoms--> molecules--> organelles--> cells--> tissues--> organs-->
organisms --> population --> community--> biosphere
What is the lowest level of organization with all the properties of life?
Cells
What are the three domains of living organisms?
Bacteria, Archea, Eukarya
Phospholipid bilayer has head and tail
Hydrophilic (polar); hydrophophobic (nonpolar)
Cytoplasm
Semifluid "soup" of proteins, enzymes, dissolved salts, sugars. All the
organelles and the nucleus float in the cytoplasm
Nucleus
Contains chromatin: a combination of DNA and associated proteins
Nucleolus
an area where synths of ribosomal genes rRNA takes place
Rough Endoplasmic Reticulum
Sorts and modifies protein chains delivered by bound ribosomes
Smooth Endoplasmic Reticulum
Lacks ribosome; site of lipid synthesis
Golgi Body
Connects with the smooth ER, completes lipid synthesis and sorters
proteins to their correct destination in small vesicles
Vesicles
Transport proteins and lipid to the cell surface; bring proteins and
lipids into cells from the cell surface, digest compounds
Lysosomes
Intracellular digestion; contain a potent brew of digestive enzymes
Peroxisomes
Break down fatty acids, amino acids, alcohol
Mitochondria
A double membrane bound organelle that makes ATP for cellular
energy
Chloroplast
Plants only; a double membrane- bound organelle that makes sugar
from sunlight and CO2 during photosynthesis
Cytoskeleton
Provides cell shape
Cell Wall
A tough rigid structure made up of cellulose chitin
What organelle is responsible for protein synthesis?
Ribosome
Why is yeast used to make bread rise?
Yeast carries out fermentation, producing ethanol and carbon dioxide
How is mitosis different from meiosis?
Meiosis creates cells with half the chromosomes of the parent cell
A cell is in a solution in which the concentration of the solutes is higher inside the cell than outside the cell. What would you expect to happen to the cell?
It will swell and possibly burst
What is the phloem tissue in plant stems?
It conducts the energy of light to leaves
Physical factors such temperature and pH can alter enzyme activity because they have an effect on the enzyme's .
Shape
What kind of symbiosis exists between a pneumonia bacterium and a human?
Parasitism
Beeswax is an example of what kind of molecule
Lipid
In which phase of cell division do the chromosome replicate
Interphase
What happens to glucose during glycolysis?
It splits into molecules of pyretic acid
How do RNA and DNA derive their names?
From the sugar each contains
If a bacteria are placed in a strong solution of salt water, they will shrink as water moves out of the bacteria. What is this process called?
Osmosis
What does an enzyme do?
Speeds up chemical reaction
Two organisms live in a relationship from which both benefit. What is this called?
Mutualism
Which structure is found in protists but not in monerans?
Golgi apparatus
Rod shaped bacteria
Bacilli
Spiral shaped bacteria
spirilla
Round shaped bacteria
Cocci
What is the term for the breakdown of glycogen into glucose subunits?
Hydrolysis
Hydrolysis
The chemical breakdown of a compound due to reactions with water
Anabolism
Synthesis from simple to complex molecules
Catabolism
Break down of complex molecules to simpler molecules
Which organelle provides storage space for the cell?
Vacuole
What is a byproduct of fermentation in muscle cells?
Lactic acid
Telophase
Phase of mitosis in which new nuclear membranes form around sets of
chromosomes
Names a final step in protein synthesis
Amino acid bonds
Foods with a high salt content do not have to be refrigerated. What natural process prevents these foods from spoiling?
Osmosis
What is necessary for active transport through a membrane to take place?
ATP
What are saturated fats saturated with?
Hydrogen atoms
How many pairs of homologous chromosomes do humans have?
23
What happens to mRNA as it reached the cytoplasm?
It attaches to a ribosome [Show Less]