TEST ONE SAPLING
How many protons, neutrons, and electrons does a neutrally charged Hydrogen atom have? Use the periodic table entry for Hydrogen to answer the question. number of protons: number of neutrons: number of electrons:
- 1 - 0 - 1
How does the specific heat of water influence biological systems?
- A high specific heat enables organisms to resist temperature fluctuations.
Which of the statements are examples of hypotheses? - A scientist proposes that the protein shell of the virus contains its genetic material. - A scientist concludes that some viruses contain DNA within their protein shells. - A scientist predicts that the DNA molecule of the virus contains its genetic material. - A scientist observes that viruses are composed of a DNA molecule contained in a protein shell.
- A scientist proposes that the protein shell of the virus contains its genetic material. - A scientist predicts that the DNA molecule of the virus contains its genetic material.
Why is carbon so prevalent in biological molecules, such as lipids? (multiple answers) - Carbon can form up to four covalent bonds with other atoms. - Carbon can share electrons with hydrogen to form hydrocarbons. - Carbon is one of the rarest elements on earth. - Carbon‑based molecules can take on a number of different structures. - Carbon‑based molecules tend to be extremely unstable.
- Carbon can form up to four covalent bonds with other atoms. - Carbon can share electrons with hydrogen to form hydrocarbons. - Carbon‑based molecules can take on a number of different structures.
How does a dehydration reaction differ from a hydrolysis reaction? (multiple answers) - Monomers split apart from polymers in dehydration, and polymers are built by hydrolysis. - Dehydration creates polymers by joining monomers, and hydrolysis splits polymers into monomers. - Monomers dissolve in water in hydrolysis, and water evaporates from monomers in dehydration. - A water molecule is removed during dehydration and added in hydrolysis.
- Dehydration creates polymers by joining monomers, and hydrolysis splits polymers into monomers. - A water molecule is removed during dehydration and added in hydrolysis.
In 1913, the chemist Niels Bohr suggested a model for the structure of the atom. He proposed that electrons travel around the nucleus in well‑defined orbits. He collected data of the atomic emission spectrum for the hydrogen atom and extended it to a model for other atoms. By 1925, scientists proposed a new kind of mechanics called quantum physics and more advanced research was conducted on atoms larger than hydrogen. New data and conclusions led to a more accurate model of electron motion. A new theory for the model of the atom was accepted, refining Bohr's model of the atom. Based on the history of the model of the atom, which statement about scientific theory is true? -A scientific model or idea is elevated to a theory when it is liked by most scientists. -Scientific theories are proven wrong when new data and conclusions are revealed. -Because Bohr's model was replaced, it is considered a hypothesis rather than a theory. -Further scientific results may be used to modify, dispute, or even falsify a theory.
- Further scientific results may be used to modify, dispute, or even falsify a theory.
The scientific method is a set of techniques for gaining new knowledge about the world in which we live. However, these techniques come with a rigid set of rules that are sometimes misinterpreted. Identify the statements that accurately describe science and the scientific method. - Science is a process that is not limited by the types of questions it can answer. - Science is a process that is limited to answering questions about the natural world. - Scientific theories are concrete and indisputable explanations for natural phenomena. - Scientific theories can be made obsolete by new experiments or observations. - Scientific findings are based on carefully tested and scrutinized observations. - Scientific findings can always be relied upon as fact.
- Science is a process that is limited to answering questions about the natural world. - Scientific theories can be made obsolete by new experiments or observations. - Scientific findings are based on carefully tested and scrutinized observations.
Brendan frequently comes home from soccer practice with muddy socks. Previous pretreatment techniques (such as presoaking in bleach) have not worked to remove the stains. Brendan had heard about a new product that was advertised to completely remove mud stains by pretreating with the product for 24 hours. Brendan was tired of wearing stained socks and hypothesized that the new product would get the mud stains out of his soccer socks. Which statement describes the best experimental design to test the new product's effectiveness? - Test new socks, worn once to soccer, by pretreating one sock for 24 hours while leaving the other sock untreated. - Test old socks, stained previously, by pretreating one sock for 24 hours while leaving the other sock untreated. - Test new socks, worn once to soccer, by pretreating one sock first with bleach and then new product for 24 hours while leaving the other sock untreated. - Test new socks, soiled with grape juice, by pretreating one sock for 24 hours while leaving the other sock untreated. Which example represents the control for Brendan's experiment? - untreated new sock - bleach pretreatment - untreated old sock - pretreated new sock
- Test new socks, worn once to soccer, by pretreating one sock for 24 hours while leaving the other sock untreated. - untreated new sock
Which statements accurately describe the polarity and electronegativity of water? - Water has polar bonds and a linear symmetrical shape, so it is polar. - The atoms of the water molecule are held together by covalent bonds. - The oxygen atom in a water molecule is strongly electronegative. - Strong covalent bonds are formed between two or more water molecules. - Water molecules are polar and thus associate with each other through hydrogen bonds.
- The atoms of the water molecule are held together by covalent bonds. - The oxygen atom in a water molecule is strongly electronegative. - Water molecules are polar and thus associate with each other through hydrogen bonds.
If the solid form of most molecules is heavier than the liquid form, why does ice float? - Frozen water molecules repel water molecules that are in the liquid state. - The crystalline structure of ice is denser than liquid water. - A water molecule is larger in the liquid state than in the solid state. - The crystalline structure of ice is less dense than liquid water. Which examples illustrate how the property of ice floating on water supports life on Earth? - Aquatic animals are trapped in solid ice during the winter. - Ice provides a habitat for land-dwelling arctic and antarctic animals. - The habitat for arctic and antarctic predators is lost during winter. - Aquatic animals can survive when the surface of water freezes.
- The crystalline structure of ice is less dense than liquid water. - Ice provides a habitat for land-dwelling arctic and antarctic animals. - Aquatic animals can survive when the surface of water freezes.
How does the high specific heat capacity of water help to regulate body temperature? - Water can be broken down by the body to help regulate body temperature. - Water can release a large amount of heat before changing temperature. - Water in the body can be quickly cooled when an individual is too hot. - Water can be used to cool the body through evaporative cooling.
- Water can release a large amount of heat before changing temperature. - Water can be used to cool the body through evaporative cooling.
Why does oil not dissolve in water? - Oil is less dense than water, which causes it to separate from water instead of dissolving. - Water molecules form hydrogen bonds with each other and exclude oil molecules. - Water molecules form stronger associations with other polar molecules than with oil. - Hydrogen bonds form between oil molecules, causing them to aggregate.
- Water molecules form hydrogen bonds with each other and exclude oil molecules. - Water molecules form stronger associations with other polar molecules than with oil.
What is a peptide bond? - a covalent bond formed when the carboxyl group of one molecule reacts with an amino group of a different molecule - an ionic bond formed when the hydroxyl group of one molecule reacts with an amino group of a different molecule - a covalent bond formed when a nitrogen atom in one molecule reacts with a carbon atom in a different molecule - an ionic bond formed when a nitrogen atom in one molecule reacts with an oxygen atom in a different molecule
- a covalent bond formed when the carboxyl group of one molecule reacts with an amino group of a different molecule
What property of water molecules leads to the high surface tension of liquid water?
- formation of hydrogen bonds between water molecules
Carbohydrates, or saccharides, are classified into three main types according to their structure: monosaccharides, disaccharides, and polysaccharides. Identify the pair of monosaccharides. - glucose and galactose - glycogen and lactose - fructose and starch - sucrose and galactose
- glucose and galactose
Carbohydrates, or saccharides, are classified into three main types according to their structure: monosaccharides, disaccharides, and polysaccharides. Identify the pair of polysaccharides. - lactose and galactose - cellulose and sucrose - glycogen and cellulose - glucose and glycogen
- glycogen and cellulose
Which of the given substances can be classified as a compound? - hydrochloric acid (HCl) - diamond (Cn) - sucrose (C12H22O11) - sodium (Na) - chlorine gas (Cl2) - table salt (NaCl)
- hydrochloric acid (HCl) - sucrose (C12H22O11) - table salt (NaCl)
Carbohydrates, or saccharides, are classified into three main types according to their structure: monosaccharides, disaccharides, and polysaccharides. Identify the pair of disaccharides. - galactose and cellulose - lactose and sucrose - lactose and glucose - starch and sucrose
- lactose and sucrose
DNA and RNA are nucleic acids. Like other polymers, nucleic acids are made up of repeating units called monomers. What are the monomers, or building blocks, of nucleic acids? - monosaccharides - amino acids - nucleotides - fatty acids
- nucleotides
Trace elements make up a ________ percentage of the elements found in living organisms and are _________ for normal metabolic function.
- small - critical
Select all the domains of life. -Archaea -Plantae -Animalia -Bacteria -Eukarya -Fungi
-archaea -bacteria -eukarya
Place the taxonomic ranks in the correct order from the most general rank to the most specific rank. -genus -order -family -domain -class -species -kingdom -phylum
1) domain 2) kingdom 3) phylum 4) class 5) order 6) family 7) genus 8) species
Consider the elements, listed, found in the human body. Which two are major components, making up at least 3% each of the human body? - magnesium - nitrogen - oxygen - selenium - cobalt How many single covalent bonds does each element generally form? Enter your answers as numerals; for example, 7. carbon: hydrogen:
1) nitrogen 2). oxygen carbon: 4 hydrogen: 1
Arrange the levels of large‑scale biological organization.
1) organism 2) population 3) community 4) ecosystem 5) biome 6) biosphere
For each example, identify if the food contains mostly saturated or unsaturated fatty acids. 1) Olive oil, which is a liquid at room temperature, is used in cooking pasta. 2) Coconut oil, which is a solid at room temperature, can be used as an alternative to butter. 3) Butter, which is a solid at room temperature, is often used in cooking. 4) The oil inside flaxseed oil pills is liquid at room temperature.
1) unsaturated 2) saturated 3) saturated 4) unsaturated
Arrange the levels of body organization from the simplest (less organization) to the most complex (more organization). -organ system -molecule -organ -organism -tissue -atom -cell
1)atom 2)molecule 3)cell 4)tissue 5)organ 6)organ system 7)organism
Which of the samples are composed of matter? - ice on a pond - air inside a balloon - sound of a birdsong - clouds in the sky - warmth from a fire
1. Air inside a balloon 2. fog in the morning 3. ice cubes in a glass
Consider the image of oxygen. How many electrons are in the first and second electron shells of oxygen, respectively?
2, 6
The study of biology can be understood through the organizational hierarchy of life. Each level of life builds upon the next level, and this increasing complexity is what leads from molecules up to an entire ecosystem. How is the cellular level different from the other levels of life?
A cell is a collection of molecules and reactions that form the basic unit of all living things.
The study of biology can be understood through the organizational hierarchy of life. Each level of life builds upon the next level, and this increasing complexity is what leads from molecules up to an entire ecosystem. How is the community level different from the other levels of life?
A community is a collection of all the organisms living and potentially interacting in the same geographic area.
The study of biology can be understood through the organizational hierarchy of life. Each level of life builds upon the next level, and this increasing complexity is what leads from molecules up to an entire ecosystem. How is the population level different from the other levels of life?
A population is a group of interacting individuals from one species that inhabit the same geographic area.
The study of biology can be understood through the organizational hierarchy of life. Each level of life builds upon the next level, and this increasing complexity is what leads from molecules to an entire ecosystem. How is the tissue level different from the other levels of life?
A tissue is a group of similar cells that work together to perform a function.
The study of biology can be understood through the organizational hierarchy of life. Each level of life builds upon the next level, and this increasing complexity is what leads from molecules to an entire ecosystem. How is the organ system level different from the other levels of life?
An organ system is a group of multiple organs that work together to perform vital functions for the organism.
The given chemical reaction summarizes the process of photosynthesis in which plants produce glucose using light energy. 6CO2+12H2O+light⟶C6H12O6+6O2+6H2O Identify the number of each type of atom in the reactants and products for this balanced equation. C atoms in the reactants: H atoms in the reactants: O atoms in the reactants: C atoms in the products: H atoms in the products: C atoms in the products:
C atoms in the reactants: 6 H atoms in the reactants: 24 O atoms in the reactants: 24 C atoms in the products: 6 H atoms in the products: 24 C atoms in the products: 24
Biomolecules are organic molecules that are produced by living organisms to perform a variety of functions. Classify each of the biomolecules as a carbohydrate, lipid, nucleic acid, or protein. - estrogen - starch - triglyceride - collagen - glucose - RNA - antibody - DNA
CARBOHYDRATE: - glucose - starch LIPID: - triglyceride - estrogen NUCLEIC ACID: - DNA - RNA PROTEIN: - antibody - collagen
Classify the following characteristics as pertaining to cellulose, starch, or glycogen. - moderately branched - important for the structure of pine trees - used for energy storage in potatoes - unbranched - used for energy storage in liver cells - highly branched
CELLULOSE: - unbranched - important for the structure of pine trees STARCH: - moderately branched - used for energy storage in potatoes GLYCOGEN: - highly branched - used for energy storage in liver cells
Water is a polar molecule that exhibits the properties of adhesion and cohesion. Identify the examples as either cohesion, adhesion, or both. - water forms into a drop on a leaf and hangs down, but it does not drop - some insects can float on the water's surface due to high surface tension - blood flows up a narrow tube as a nurse collects a blood sample - water sticks to the cell walls of plants
COHESION: - some insects can float on the water's surface due to high surface tension BOTH: - blood flows up a narrow tube as a nurse collects a blood sample - water forms into a drop on a leaf and hangs down, but it does not drop ADHESION: - water sticks to the cell walls of plants
Classify the traits of eukaryotic nucleic acids as typical of DNA only, RNA only, or both. - contains codes for proteins - double stranded - made of nucleotides - uses uracil - single stranded - uses thymine
DNA: - uses thymine - double stranded RNA: - uses uracil - single stranded BOTH: - made of nucleotides - contains codes for proteins
Ashley hypothesizes that adding coffee grounds to the soil will help the plants grow faster. She designs a controlled experiment to determine if this hypothesis is supported. She grows one group of soybean seedlings under normal conditions. She mixes three tablespoons of coffee grounds into the soil of the second group and grows the seedlings under the same light, temperature, and watering regimen. After three weeks, she measures the height of the seedlings and compares the two groups. Identify the parts of the experiment. Place only one term in each category. You will not place all the terms. EXPERIMENTAL GROUP CONTROL GROUP DEPENDENT VARIABLE INDEPENDENT VARIABLE answer bank: - seedling height - soil - seedlings given extra water - temperature - seedlings grown without coffee grounds - seedlings grown with coffee grounds - light Would it be a good experimental design if she also, as part of the same experiment, tests seedling growth at different temperatures by growing one group at 20 ∘C (68 ∘F) and the other group at 25 ∘C (77 ∘F)? - Yes, it would enable her to compare more than one environmental factor at a time. - No, the other conditions should remain the same for the experiment to be scientifically sound. - Yes, but it is not necessary to grow one group without coffee since that is not being tested. - No, a temperature difference of 5 ∘C is not large enough to detect a significant temperature effect.
EXPERIMENTAL GROUP: - seedlings grown with coffee grounds CONTROL GROUP: - seedlings grown without coffee grounds DEPENDENT VARIABLE: - seedling height INDEPENDENT VARIABLE: - soil - No, the other conditions should remain the same for the experiment to be scientifically sound.
Phospholipids are molecules that have two regions, the head and the tail, with distinct chemical properties. Classify the descriptions as characteristics of the heads or tails of phospholipids. - phosphate rich - non polar - hydrophilic - does not mix with water
HEADS: - hydrophilic - phosphate rich TAILS: - does not mix with water - non polar
Classify these items according to whether they are descriptions or examples of monomers or polymers. - RNA - molecules composed of smaller subunits linked together - muscle protein - single molecules that can be linked together to form larger molecules - cellulose - simple sugars - nucleotides
MONOMERS: - single molecules that can be linked together to form larger molecules - simple sugars - nucleotides POLYMERS: - molecules composed of smaller subunits linked together - cellulose - muscle protein - RNA
During cellular respiration, the cell forms CO2 (carbon dioxide) and H2O (water) by breaking down C6H12O6 (glucose) and O2 (oxygen). Classify the molecules as reactants or products in the chemical reaction as reactants or products. - water - oxygen - carbon dioxide - glucose
REACTANTS: - oxygen - glucose PRODUCTS: - water - carbon dioxide
Sort the statements based on whether they describe a scientific hypothesis or a scientific theory. - scientists develop a well-tested and reliable explanation based on numerous reliable studies - a researcher suggests an untested explanation that attempts to explain something he or she observed - an ornithologist suspects that more young birds will survive in years when caterpillars are an abundant food source - a plant researcher thinks that increasing the amount of nitrogen in a fertilizer mix will improve plant growth - after conducting numerous investigations, scientists conclude that all living organisms are made of cells
SCIENTIFIC THEORY: - scientists develop a well-tested and reliable explanation based on numerous reliable studies - after conducting numerous investigations, scientists conclude that all living organisms are made of cells HYPOTHESIS: - a researcher suggests an untested explanation that attempts to explain something he or she observed - a plant researcher thinks that increasing the amount of nitrogen in a fertilizer mix will improve plant growth - an ornithologist suspects that more young birds will survive in years when caterpillars are an abundant food source
What effect do valence electrons have on the reactivity of elements?
The reaction of an element with another element is dictated by the number of electrons in each of their outermost shells.
Water accounts for 60% to 90% of the mass of every cell, and it dissolves many substances that are used or produced in cellular chemical reactions. Although it does not dissolve all substances, water is sometimes called the universal solvent. Which property of water contributes to its ability to dissolve most molecules in the cell?
Water has polar bonds and is a polar molecule.
How does evaporation help regulate body temperature?
When sweat evaporates, heat is removed from the skin, which cools the body.
When cells link monomers together to construct polymers, which process is used to make the monomers form bonds with each other? - dissolution - hydrolysis - cohesion - dehydration - evaporation
dehydration
what are the two components of a triglyceride?
glycerol and fatty acids
Which process is used to break down polymers into monomers? - dissolution - adhesion - evaporation - dehydration - hydrolysis
hydrolysis
Classify each property of a functional group as a characteristic of the hydroxyl group (−OH), the phosphate group (−PO4),or the amino group (−NH2). - positively charged under cellular conditions - polar and forms hydrogen bonds - can combine with hydrogen from another group to form H2O in dehydration reactions - forms peptide bonds with carboxyl groups (-COOH) - strongly charged - used to make one end of a lipid molecule hydrophilic
hydroxyl group (−OH): - polar and forms hydrogen bonds - can combine with hydrogen from another group to form H2O in dehydration reactions phosphate group (−PO4): - strongly charged - used to make one end of a lipid molecule hydrophilic amino group (−NH2): - positively charged under cellular conditions - forms peptide bonds with carboxyl groups (-COOH)
The famous Miller-Urey experiment was conducted in 1953. This experiment tested the hypothesis that primitive Earth conditions were favorable for creating complex organic compounds from simple compounds. Classify the compounds according to whether they were inputs or outputs in this experiment. - methane - ammonia - biomolecules - amino acids - water
inputs: - water - ammonia - methane outputs: - amino acids - biomolecules
Which statement describes a functional group?
part of a larger molecule that can react with other atoms or molecules
Classify each statement or molecule as a polar bond or nonpolar bond. - the bond between oxygen and hydrogen in water (H2O) - the bond between nitrogen atoms in diatomic nitrogen (N2) - the atoms in a covalent bond have partial charges - electrons are not equally shared by the atoms in a covalent bond - electrons are equally shared between atoms in a covalent bond
polar bond: - the bond between oxygen and hydrogen in water (H2O) - electrons are not equally shared by the atoms in a covalent bond - the atoms in a covalent bond have partial charges non polar bond: - the bond between nitrogen atoms in diatomic nitrogen (N2) - electrons are equally shared between atoms in a covalent bond
Scientists can measure the acidity of water using the pH scale. Three different types of water were collected and placed into the beakers shown. Identify the pH measurements for the pure water, rain water, and acid rain contained in the beakers. - pH 5.6 - pH 4.3 - pH 7.0
pure water: - pH 7.0 rain water: - pH 5.6 acid rain: - pH 4.3
Identify the solute and solvent of each solution. salt water: salt- water- nail polish removed with nail polish remover (acetone): acetone- nail polish- cup of instant sports drink: drink powder- water- sada water: water- carbon dioxide- household vinegar: water- acetic acid-
salt water: salt- solute water- solvent nail polish removed with nail polish remover (acetone): acetone- solvent nail polish- solute cup of instant sports drink: drink powder- solute water- solvent sada water: water- solvent carbon dioxide- solute household vinegar: water- solvent acetic acid- solute