BIO-1050 Exam 1
Which of the following is the smallest unit of life?
Cells
Humans cannot digest this polysaccharide, which is why it is known as fiber
Cellulose
Which human body system is responsible for carrying gases, wastes, nutrients, etc. throughout the body
Circulatory (cardiovascular)
What type of bond is the most common in living organisms and involves the sharing of electrons?
Covalent
Select the choice where bond strength is ranked strongest to weakest within cells:
Covalent, ionic, hydrogen
DNA acts as a ________________ for living things.
DNA acts as a blueprint for living things.
DNA codes for ______, which then creates _________, which creates life.
DNA codes for RNA, which then creates protein, which creates life.
Select the largest uniy from the choices provided:
Digestive system
Which human body system is responsible for the secretion of hormones, such as growth hormone and adrenaline
Endocrine
What is stored in bonds?
Energy a) Endothermic reactions b) Exothermic reactions
Which of the following does not apply to a base?
It has a pH between 5 and 10
What type of reasoning combines many observations into one general statement to be tested?
Inductive
A polar molecule will always have at least three different atom types
False
A theory is a guess a scientists makes to explain what he or she observes, which will be proven right or wrong by experimentation. An hypothesis is a general uniting principle of science, upheld by observation and many experiments.
False
In practice, the scientific method is a linear process that is always used the same way by scientists.
False
Learning the names for the parts of the brain is an example of studying physiology, while learning about how the brain sends signals to control various functions in the body is an example of studying anatomy.
False
Viruses are considered living organisms because they are made of cells and can reproduce on their own. They also have their own metabolism.
False They need a host
Choose the taxonomic description which would indicate a lifeform most closely related to a human.
Genus Homo
Which carbohydrate is an important monosaccharide made by plants and is used to build most of the larger carbohydrates?
Glucose
Which of the following carbohydrates do humans use to store energy short-term in muscles and in our liver?
Glycogen
Which characteristic of water helps in protection against extreme cold?
Ice is less dense than water
How does a protein's shape/structure relate to its function?
If protein is the wrong shape it will not function
Which kingdom in the Domain Eukarya is a diverse group that contains both autotrophs and heterotrophs, single-celled and multicellular organisms, and has plant-like, fungal-like, and animal-like organisms?
Kingdom Protista
Which type of organic molecule is pictured here?
Lipid
1Which human body system helps fight against pathogens and includes the thymus, spleen, tonsils, and bone marrow?
Lymphatic/Immune
A(n) ___________________ fat is solid at room temperature and includes straight, long chain hydrocarbons with no double bonds
Saturated
Biological buffers:
Stabilize pH by absorbing excess H+ or OH- ions in a solution.
What is the pH of the stomach?
Stomach pH 2
When performing an experiment, you need to test the contribution of a single variable to an observation. What was the variable in the first experiment
Sunscreen expiration date
Which carbohydrate category does glucose belong to?
Monosaccharide
Negative Feedback
Negative Feedback is the primary way in which homeostasis is maintained: Example - How does your body respond when you are out in the heat? - We sweats to cool down and moves to remove heat. Blood vessels are dilating to get rid of the heat, therefore we may become red. How does your body respond when you are in the cold air conditioning? - We shiver which can generate heat and decrease our blood vessel diameter size to warm us up
Which human body system CONTROLS all of the body's actions, including both voluntary and involuntary actions?
Nervous
Do most lipids dissolve in water?
No
Are Viruses Considered Living Organisms? Explain.
No, a virus is not classified as a living organism by several scientists since they cannot reproduce on their own since they need a host to reproduce. The virus does hold its own genetic material, but it needs a post to pass it along. They can evolve but they lack several of the characteristics of life, therefore they cannot be classified as living
Based on the example provided, which of the following was made as an observation
Noticing a sunburn on your face, shoulders, and arms.
Because the oxygen and hydrogen atoms within a water molecule share electrons unequally, water is ____________
Polar
Which statement regarding protein function is INCORRECT?
Protein structure is simple showing little molecular diversity
To what group of organic compounds do most enzymes belong?
Proteins
Which of the following organic chemicals is the most abundant in your body?
Proteins
The type of atom that you have (for example carbon, gold, or aluminum) depends on the number of which particle in the nucleus?
Protons
Select the element choices which are ranked among the four commonest in living organisms. Select all that apply
a. Carbon b. Hydrogen
Provide two examples of molecules
a. Water (H2O) b. Ethanol c. Nitrogen (N2)
What are the six properties of water critical to life? Select all correct choices.
a. Water is polar b. Water has high specific heat
organization
all living things are made of cells; multicellular organisms have biological organization, including the levels of tissues, organs, and organ systems
The building blocks of proteins are ____molecules
amino acid
Nonpolar Covalent bond
atoms share electrons equally; the molecule is electrically balanced
Polar Covalent bond
atoms share electrons unequally because one atom has a stronger attraction for the shared electrons; these bonds result in the molecule having partial charges
Antibodies
attach to invaders (such as bacteria & viruses) to help your immune system defeat them
Biology
The study of life
What type of lipid is used primarily for energy storage, including the fats and oils?
Triglycerides
Atoms are like Lego bricks that can be put together to build molecules
True
Exothermic reactions like burning hydrogen fuel release energy.
True
If homeostasis is not maintained, then disease or even death can result.
True
Sweating cools you down because water requires a large amount of energy to evaporate.
True
The word theory is casually used to mean a hunch, guess, or opinion, but a scientific theory is supported by evidence and has been repeatedly tested.
True
Which of the following is true about a saturated fat?
Typically stored at room temperature
Which human body system uses the kinesys to remove waste from blood?
Urinary
Compare cohesion and adhesion
a) Adhesion - water molecules stick/attract to most other substances b) Cohesion - water molecules stick/attract to other water molecules i) contributes to the surface tension of water (allows the surface of water to resist external force, such as when small insects walk on water)
Explain how atoms are like legos/blocks that make up molecules. Give examples of molecules
a) Atoms are like lego blocks/bricks. b) While molecules are what is built with those lego blocks/bricks c) Atoms (like lego blocks/bricks) can be combined to form molecules i) Examples of molecules include: (1) Water (H2O) ii) Ethanol (CH3CH2OH) d) Most atoms bond with other atoms. e) Atoms can bond with atoms of the same element or atoms of different elements. f) When one atoms pulls an electron away from another atom you end up with ions (one ion is negatively charged and the other is positively charged).
Describe the basic structure of an atom, including protons, neutrons, and electrons.
a) Atoms are made up of: i) Protons & neutrons in the nucleus ii) Electrons are found around the nucleus in energy levels
Describe hydrogen bonding between water molecules.
a) Bonds between water molecules are known as Hydrogen bonds. b) Water's unique properties are all because it is a polar molecule that forms hydrogen bonds.
What common buffer is in the blood?
a) Buffers stabilize blood pH by absorbing excess H+ or OH- ions. b) A common blood buffer consists of carbonic acid (H2CO3) and bicarbonate ion (HCO3- i) When blood becomes too acidic (too many H+ ions), the bicarbonate ions in the blood will bond to and absorb the excess H+ ions. ii) When blood becomes too basic (too many OH- ions), carbonic acid will release H+ ions that bond to and absorb the OH- ions to neutralize them, forming water.
What six elements are also in small quantities in the human body?
a) Calcium b) Phosphorus c) Sulfur d) Sodium e) Chlorine f) Magnesium
Name the 11 Human Body Systems.
a) Circulatory (Cardiovascular) b) Digestive c) Endocrine d) Excretory (Urinary) e) Integumentary (Cutaneous) f) Lymphatic/Immune g) Muscular h) Nervous i) Reproductive j) Respiratory k) Skeletal
Proteins are very diverse in function. Give examples of protein functions.
a) Coded for by DNA b) Enzymes - regulate chemical processes & help digest food c) Antibodies - attach to invaders (such as bacteria & viruses) to help your immune system defeat them d) Protein Hormones - includes endorphins, serotonin, insulin and many, many more e) The names of most proteins end with "in" - for example hemoglobin, insulin, myosin, pepsin, etc.
Feedback Loop
a) Components of the feedback loop: i) Stimulus: Disrupts homeostasis by increasing or decreasing a controlled condition that is monitored ii) Receptors: Monitor the environment and report perceived changes by sending input to control center iii) Input: Nerve impulses or chemical signals sent from receptors to control center iv) Control Center: Receives signal from receptor and formulates a response that provides output v) Output: Nerve impulses or chemical signals sent from control center to effectors vi) Effectors: Carry out the response from the control center, bringing about a change vii) Response: Alters the initial condition negative feedback minimizes/negates it; positive feedback enhances it) viii) Returns to Homeostasis: Response brings controlled condition back to normal
What is DNA? Where is DNA located in eukaryotic cells?
a) DNA is a large molecule also known as Deoxyribonucleic Acid b) Found in the cell's nucleus
Briefly explain how DNA is a blueprint for a living thing: DNA—RNA—protein--living organism
a) DNA is our genetic make up and the order must be exact, or we have mutations in our genes. Everyone has a different order for their DNA, but A & T must go next to each other and C & G must go in the same line across from one another. The DNA tells the amino acids how to lineup as previously stated to form the perfect protein. The DNA is found in the nucleus and RNA which is particle copies of DNA are made in the nucleus, which leaves the nucleus and go out to the cytoplasm (the material within a cell outside of the nucleus) In the cytoplasm, RNA joins up with a ribosome (protein-building machine) Together, the ribosome and RNA are used to stick together in a chain based on the RNA code (copied from DNA) The growing chain of amino acids bends, folds, and sticks together forming a perfectly shaped protein that will go off to perform one of many functions.
What are elements? What are the four most common elements in the human body?
a) Different types of atoms (known as elements) have symbols that represent them. i) Oxygen (O) ii) Hydrogen (H) iii) Carbon (C) iv) Nitrogen (N)
Compare organisms in the three domains of life (Archaea, Bacteria, and Eukarya).
a) Domain Bactria (also known as Eubacteria) i) Prokaryotic (lack a nucleus) & single-celled ii) Includes only one Kingdom of same name - Bacteria/Eubacteria iii) Examples: Bactria that helps when you are sick or make you sick. Ones that help with decomposing. b) Domain Archaea (also known as Archaebacteria) i) Prokaryotic (lack a nucleus) & single-celled ii) Includes only one Kingdom of same name - Archaea/Archaebacteria iii) Examples: DNA in structural differences, the disease c) Domain Eukarya i) Eukaryotic (cells contain a nucleus and more complex organelles) ii) Most are multicellular (made of many cells) iii) Includes 4 Kingdoms: (1) Kingdom Protista - very diverse group (a) contains organisms that have eukaryotic cells but are not true plants, fungi, or animals (b) contains both autotroph protists (make own food) and Heterotroph protists (consume/feed on other organisms) (c) most are single-celled, but some are multicellular (d) examples include algae, paramecia, slime molds, etc. (2) Kingdom Fungi (a) all heterotrophs (feed on other organisms) à This is often something that people don't realize - Fungi do NOT make their own food like plants (b) mostly multicellular; a few are single-celled (ex: yeasts) (3) Kingdom Plantae (a) Plants (make own food through photosynthesis) (b) Multicellular (4) Kingdom Animalia (animals) (a) Heterotrophic (b) Multicellular
Compare endothermic and exothermic reactions.
a) Endothermic reactions i) absorb energy and store that energy in the bonds of the products formed ii) ex: plants store energy from sunlight in sugars during photosynthesis; iii) ex: your body stores excess energy in fat molecules which can cause weight gain b) Exothermic reactions i) release energy when high energy bonds in molecules are broken ii) ex: your body breaks down sugars, releasing energy required for your cells to function
What are the two major functions of carbohydrates?
a) Energy production b) Short term energy storage
Bases
a) Has a pH greater than 7 (also referred to as alkaline) i) Release a greater concentration of hydroxide ions [OH-] than hydrogen ions [H+] ii) The more hydroxide ions that are released, the more basic the substance iii) The higher the pH the more basic (pH 14 is more basic than 10) iv) Often feel slippery v) Taste bitter (think very dark chocolate) vi) Often used as household cleaners Examples include: milk of magnesia and ammonia
Acids
a) Has a pH less than 7 i) Release a greater concentration of Hydrogen ions [H+] than hydroxide [OH-] ii) The more hydrogen ions that are released, the more acidic the substance iii) The lower the pH the more acidic (pH 2 is more acidic than 5) iv) Often taste sour v) Corrode metals vi) Examples include: lemon juice, stomach acid, and coffee
Water resists changes in temperature due to a high specific heat. What is the significance of this?
a) High specific heat - water resists changes in temperature i) Water is therefore stabilizing for aquatic environment temperatures ii) Also, water is stabilizing inside living organisms, helping maintain homeostasis
What is a hypothesis? What is a scientific theory and how does it differ from a hypothesis?
a) Hypothesis - A suggested explanation that I could then test. i) The word theory is often casually used in everyday life be used to mean an opinion, hunch, or guess. ii) Sometimes the term theory is also confused with hypothesis. a) Scientific Theory i) explanation supported by explanation supported by scientific evidence ii) fortified by facts iii) repeatedly tested (1) In order to reach the level of scientific theory, a scientific theory must be backed by science facts and evidence supporting it, with repeated testing.
Ice floats on liquid water because it is less dense. What is the significance of this?
a) Ice Floats - frozen water is slightly less dense than liquid water because when it freezes, the hydrogen bonds lock the water molecules farther apart from one another than in liquid form i) Why ice floats on a frozen pond, allowing fish to survive in the water underneath
What is homeostasis? Give examples of conditions that humans must maintain in homeostasis.
a) It is a state of balance b) It requires that an organism maintain many conditions within a certain range, including: i) pH levels, blood glucose, internal body temperature
What is the range of the pH scale? Compare pH values of acids and bases. What pH is neutral?
a) It ranges from 0 to 14 b) Acids: 0 to 7 c) Neutral: 7 d) Bases: 7 to 14
Describe the 4 kingdoms of the Domain Eukarya. Which kingdom are humans in?
a) Kingdom Protista - very diverse group i) contains organisms that have eukaryotic cells but are not true plants, fungi, or animals ii) contains both autotroph protists (make own food) and Heterotroph protists (consume/feed on other organisms) iii) most are single-celled, but some are multicellular iv) examples include algae, paramecia, slime molds, etc. b) Kingdom Fungi i) all heterotrophs (feed on other organisms) à This is often something that people don't realize - Fungi do NOT make their own food like plants ii) mostly multicellular; a few are single-celled (ex: yeasts) c) Kingdom Plantae i) Plants (make own food through photosynthesis) ii) Multicellular d) Kingdom Animalia (animals) i) Heterotrophic ii) Multicellular
Describe and give examples of each level in the organization of life from atoms through the biosphere. What is the smallest unit of life?
a) Life on Earth is organized into levels based on degree of complexity, ranging from very small and simple (atoms) to very large and complex (biosphere) b) The organization of life is a hierarchy with the larger levels enveloping the smaller levels Cellular Organization Populational Organization
Phospholipid
a) Made of 2 fatty acids & a phosphate group attached to glycerol b) Make up cell membranes c) Hydrophilic polar ends attracted to water d) Hydrophobic nonpolar ends avoids water
Steroids
a) Made of four interconnected carbon rings b) Includes cholesterol, cortisol, lipid hormones (estrogen, testosterone, etc.) c) Cholesterol bonds to phospholipids to form cell membranes, NOT cell walls
What are proteins made of? Where do we get those molecules from?
a) Made up of small molecules called Amino Acids i) (there are 20 different amino acids that vary based on different side chains) b) Proteins are the source of nitrogen in the food we eat c) Amino acids form long chains known as Polypeptides that fold, coil, and twist to form large protein structures
What is a monomer? Identify the monomers of proteins, lipids, and carbohydrates.
a) Monomers - building blocks (single small molecules) that make up larger molecules (mono = one) b) One way to think of a monomer is that it is like a link in a chain. The chain would be the larger molecule and the link would be a single molecule (monomer) in the chain. c) Biomolecules are the building components of strings of monomers or carbohydrates, lipids, proteins and nucleic acids i) Carbohydrates (1) Monosaccharides - simplest sugars made up of one (mono-) sugar (-saccharide) (a) Glucose - fundamental sugar made by plants during photosynthesis (b) Fructose - significantly sweeter; found in fruits ii) Lipids (1) Glycerol and fatty acids iii) Proteins (1) Amino acids
Which of the following are unique properties of water that occur due to hydrogen bonding? (CHECK ALL THAT APPLY)
a. Adhesion - water molecules stick to many other substances b. Frozen water floats because it is less dense than liquid water c. Cohesion - water molecules stick together d. Water is a great solvent and dissolves many other substances
Return to set point
blood sugar levels raise back into normal range
Starch
i) (ex: amylose) - molecule plants use to store energy (1) Made of many glucose molecules bonded together
Endocrine System
i) A growth hormone, adrenaline ii) Glands that secrete hormones, hearts
Reproductive System
i) Allows for animals to reproduce ii) Reproductive organs: ovaries, teste,
Circulatory/Cardiovascular System
i) Blood carries blood and gases your body needs along with nutrients ii) Blood, gases, nutrients, heart, arteries, veins, capillaries vessels
Digestive System
i) Breaks down and absorbs food for nutrients ii) Mouth, saliva, stomach, small intestines, large intestines
Nervous System
i) Coordinates the body, voluntary and involuntary actions ii) Brian and spinal cord
Excretory/Urinary System
i) Exit of waste, sweating, urine ii) Bladder, kidneys
Kingdom Animalia (animals)
i) Heterotrophic ii) Multicellular
respirtory system
i) In take of Oxygen and out of CO2 ii) Lungs
Muscular System
i) Muscle helps move bone ii) 3 main types of muscle tissues: skeletal, smooth, cardiac
Kingdom Plantae
i) Plants (make own food through photosynthesis) ii) Multicellular
Populational Organization
i) Population - group of similar organisms living in the same place ii) Species - all populations of a specific organism: members of a species are similar in appearance and are able to interbreed (ex: Homo sapiens) iii) Community - all species occupying the same region iv) Ecosystem - a community and their interactions with the nonliving environment v) Biosphere - all ecosystems on the planet; contains all parts of the Earth
Integumentary (Cutaneous) System
i) Protects organs ii) Skin
Skeletal System
i) Provides support, protects organs, produces blood cells from bone marrow ii) Bones
Lymphatic/Immune System
i) Surrounds and protects lymph's to blood. Keeps you safe against pathogens. Helps support immune system ii) Lymph nodes, thymus, spleen, tonsils, bone marrow
Hydrogen bond
i) Very weak but vital to biology ii) Occur between the partial positive atom of one polar molecule and the partial negative atom of a different molecule; causes attractions between nearby polar molecules iii) Example: water molecules are attracted to each other (the partially negative oxygen of one water molecule is attracted to the partially positive hydrogen in another water molecule)
Endothermic reactions
i) absorb energy and store that energy in the bonds of the products formed ii) ex: plants store energy from sunlight in sugars during photosynthesis; iii) ex: your body stores excess energy in fat molecules which can cause weight gain
Kingdom Fungi
i) all heterotrophs (feed on other organisms) à This is often something that people don't realize - Fungi do NOT make their own food like plants ii) mostly multicellular; a few are single-celled (ex: yeasts)
Cellular Organization:
i) atom - basic unit of matter (ex: carbon, hydrogen, nitrogen, oxygen) ii) molecule - combination of atoms (water - H2O) iii) Macromolecule - combination of smaller molecules (ex: DNA) iv) Organelle - cellular structure that performs a specific function (ex: nucleus) v) Cell - smallest level of organization that is considered alive; smallest unit of life vi) Organismal Organization: vii) Tissue - groups of cells that act as a unit and perform a specific function (ex: cardiac tissue) viii) Organ - group of tissues that work together to perform a specific function (ex: heart) ix) Organ System - group of organs working together (ex: circulatory system) x) Organism - complex organisms consist of various organ systems working together (ex: human) xi) The smallest unit of life is a Cell
Kingdom Protista - very diverse group
i) contains organisms that have eukaryotic cells but are not true plants, fungi, or animals ii) contains both autotroph protists (make own food) and Heterotroph protists (consume/feed on other organisms) iii) most are single-celled, but some are multicellular iv) examples include algae, paramecia, slime molds, etc.
Glycogen
i) molecule animals use to store carbohydrate energy (1) Made of many glucose molecules bonded together (2) Stored in muscles and in the liver à if not used in about one day it gets depleted (3) Animals store energy long term in fat (which is a lipid NOT a carbohydrate)
Cellulose
i) most common structural compound in plants (1) Made of many glucose molecules bonded together (2) Most common organic compound on the planet! (3) Humans cannot digest cellulose à Cellulose is often referred to as fiber, which is important for proper digestion & "keeps things moving" through the intestines.
Exothermic reactions
i) release energy when high energy bonds in molecules are broken ii) ex: your body breaks down sugars, releasing energy required for your cells to function
What type of bond would you predict between sodium, which has a valence number of 1, and chlorine, which has a valence number of 7?
iconic
Protein Hormones
includes endorphins, serotonin, insulin and many, many more
What type of bond forms when one atom pulls an electron away from another atom?
ionic
Water has a high specific heat, which means:
it takes a lot of energy to raise or lower its temperature
Growth and Development
living organisms have genetic material (DNA) that codes for growth (getting larger) and development (changing in shape or function)
Reproduction
living things have offspring and pass on genetic material (DNA) to their offspring
Response to Stimuli
living things respond to both internal and external stimuli, including eating when hungry (internal stimuli) or fleeing from danger (external stimuli); for example, plants also grow toward the external stimulus of sunlight)
Triglyceride
made of 3 fatty acids attached to glycerol i) Provide energy storage ii) Also known as fats & oils (ex: butter, peanut butter, oils, white parts of meat) iii) Saturated fats (1) contain fatty acids with no double bonds between carbons (the fatty acid chains are therefore saturated with hydrogens) (2) the fatty acid chains are straight and can easily pack together (3) makes them solids at room temperature (4) usually made by Hydrogen (ex: butter, bacon fat) iv) Unsaturated fats (1) contain fatty acids with double bonds between the carbons (2) the fatty acid chains are bent/kinked and will not pack together tightly (3) makes them liquids at room temperature (4) usually made by Carbon (ex: olive oil, corn oil)
Disaccharides
made up of two monosaccharides bonded together i) Sucrose = glucose + fructose covalently bonded; a.k.a table sugar (1) * Monosaccharides and disaccharides are quick sources of energy that are easily processed.
Homeostasis
maintaining a regulated balance, including pH, temperature, water concentration, and other conditions
Oxygen, carbon, hydrogen and nitrogen are the four:
most predominant elements in the human body.
Buffers are important in cells because buffers:
neutralize a solution that is too acidic or basic
What pH warning does this sign indicate if this container held a strongly acidic substance?
pH 3
Ionic bonds form because:
positive and negative atoms are attracted to each other.
Enzymes
regulate chemical processes and help digest food
Covalent bonds are formed by the:
sharing of electrons
An example of a molecule with ionic bonding is:
sodium chloride (NaCl).
Hydrophilic
substances have an affinity for water and readily dissolve in water; ex: NaCl, glucose
Hydrophobic
substances lack an affinity for water and separate from water; ex: fats and oils; Think of how "oil and water don't mix"
Evolution
the ability of a population to evolve over time
Adhesion
water molecules stick/attract to most other substances
Cohesion
water molecules stick/attract to other water molecules
On this pH scale, what is the hydrogen ion concentration difference between human blood (pH 7) and ammonia (pH 11)?
x 10,000
How many amino acids within a critical protein need to alter before disease may result in the human body?
1
Unsaturated fats
(1) contain fatty acids with double bonds between the carbons (2) the fatty acid chains are bent/kinked and will not pack together tightly (3) makes them liquids at room temperature (4) usually made by Carbon (ex: olive oil, corn oil)
Saturated fats
(1) contain fatty acids with no double bonds between carbons (the fatty acid chains are therefore saturated with hydrogens) (2) the fatty acid chains are straight and can easily pack together (3) makes them solids at room temperature (4) usually made by Hydrogen (ex: butter, bacon fat)
Homeostasis:
- Is a state of balance - Requires that an organism maintain many conditions within a certain range, including the following examples: pH levels, blood glucose, internal body temperature
Counteracting response
- hormone glucagon can be released, which can have many effects and one of them is that it can cause the liver to release glucose into the blood.
What would be the pH of a neutral substance?
7
Which statement best defines a carbohydrate?
A carbohydrate is composed of carbon, hydrogen, and oxygen in a ratio of 1:2:1.
How many valence electrons does carbon have and what type of bond joins two carbons?
4; covalent
Which of the following is an element?
Carbon
Which of the following is considered a base?
Ammonia
Which of the following does NOT apply to an acid?
An example is ammonia
Which of the following is true regarding the scientific method?
An experiment is developed to test a hypothesis
Anatomy
Anatomy - the structure - "What it is" - The Form
Which domain includes organisms that are single-celled, do not have a nucleus in their cells, and live mostly in extreme environments?
Archaea/Archaebacteria
Relate the number 6 to carbon. It is an indicator of carbon's
Atomic Number
What acid/base terms would you use to describe milk, which has a pH of 7.6?
Base
The arrow is pointing to a pH that is: (9)
Basic
What is the purpose of a buffer?
Blood contains buffers - chemical compounds that help stabilize blood pH
What is the pH of blood?
Blood pH must stay between 7.35 and 7.45 for cells to function properly.
What is the biological significance of a buffer system in human tissues?
Buffers in human tissues are designed to maintain a pH of between 7.35 and 7.45
This figure illustrates a _________________. *add pictures*
Carbohydrate
What is the smallest unit described in thses choices?
Carbon
What type of bond occurs between water molecules when they are attracted together?
Hydrogen bonds
1. Select the choice which arranges the taxonomic classification levels in order from most to least inclusive .1. Domain 2. Genus 3. Kingdom 4. Species
1, 3, 2, 4
A substance that is attracted to water or dissolves in water is referred to as _____________.
Hydrophilic
Organize the steps of the scientific method listed below into their correct order: 1. Share the new knowledge with other scientists 2. Analyze and interpret data to reach conclusions 3. Recognize a problem or unanswered question 4. Design and perform an experiment to test the hypothesis 5. Develop a hypothesis to explain the problem
3, 5, 4, 2, 1
How are humans classified according to taxonomy? (domain through species)
Humans are in the Domain Eukarya and Kingdom Animalia.
Humans are in the Domain ____________ and Kingdom ____________.
Humans are in the Domain Eukarya and Kingdom Animalia.
Select the most accurate description of an atom.
A nucleus of neutrons and protons orbited by electrons.
A group of similar organisms living in the same place is known as:
A population
A protein must have the correct, perfect _______ in order to __________
A protein must have the correct, perfect shape in order to function
Of the following bonds, which one is the weakest?
Hydrogen
What kind of bond is indicated by the arrow in this diagram?
Hydrogen
Anatomy and Physiology
Form fits function à The anatomy/structure fits the physiology/function
What type of bond is the weakest and can easily be broken?
Hydrogen
Why does sweating cool the body?
High Heat of Vaporization - water requires a large amount of heat to evaporate (change from liquid to gas) - Evaporation of water removes excess energy and cools you when you sweat
Which characteristic of water helps in temperature homeostasis?
High specific heat
In the human body, nucleic acids function as _____molecules.
Information storage
Within an organism, tissues combine to form:
Organs
Which type of lipid is a key component of the cell membrane?
Phospholipid
The class of lipid that has both a hydrophilic and a hydrophobic end is _________________
Phospholipids
Physiology
Physiology - the function - "What it does" - The Function
What process do scientists use to gather new ideas and analyze information?
The Scientific Method
What is a nonpolar molecule?
The atoms share the electrons equally
negative feedback
The simple definition of negative feedback is when a variable/stimulus triggers a counteracting response in order to come back to a set point. The basic idea of a negative feedback loop: Variable (also known as a stimulus) - throws the body out of balance. Body counteracts in response Brings body back to homeostasis (ex: stable temperature)
Why is it important to life that phospholipids within a membrane have a hydrophilic head and a hydrophobic tail?
The hydrophobic tails will face inwards providing a barrier to the movement of charged molecules
What happens if your body does not maintain homeostasis?
The individual can become sick with different illnesses, disease, symptoms etc. Issues with the bodily functions and the feedback receptors. Some symptoms include: headache, nausea, fatigue, and muscle aches. It varies for different people and the different conditions which may include: Type 1 diabetes (issues with insulin)
What determines the type of atom?
The type of atom that you have depends on the number of protons in the nucleus.
Which of the following is NOT true about lipids?
They all contain fatty acids
Compare monosaccharides, disaccharides, and polysaccharides. Describe examples of each, including glucose, fructose, sucrose, cellulose, starch, and glycogen.
a) Monosaccharides - simplest sugars made up of one (mono-) sugar (-saccharide) i) Glucose - fundamental sugar made by plants during photosynthesis ii) Fructose - significantly sweeter; found in fruits b) Disaccharides - made up of two monosaccharides bonded together i) Sucrose = glucose + fructose covalently bonded; a.k.a table sugar (1) * Monosaccharides and disaccharides are quick sources of energy that are easily processed. c) Polysaccharides - made up of many monosaccharides bonded together (often containing 1000's of sugar units) i) used for energy storage or to provide structure/building material for cells ii) Cellulose - most common structural compound in plants (1) Made of many glucose molecules bonded together (2) Most common organic compound on the planet! (3) Humans cannot digest cellulose à Cellulose is often referred to as fiber, which is important for proper digestion & "keeps things moving" through the intestines. iii) Starch (ex: amylose) - molecule plants use to store energy (1) Made of many glucose molecules bonded together iv) Glycogen - molecule animals use to store carbohydrate energy (1) Made of many glucose molecules bonded together (2) Stored in muscles and in the liver à if not used in about one day it gets depleted (3) Animals store energy long term in fat (which is a lipid NOT a carbohydrate)
Why is water critical to life?
a) Most abundant molecule in living organisms b) Makes up about 60-70 % of total human body weight c) Our bodies need water to carry out basic functions of digestion, excretion, respiration, and circulation. d) Without adequate water, our body's chemical reactions would fail, and our cells would cease to function - we would die.
Are viruses considered alive? Explain why or why not
a) No, a virus is not classified as a living organism by several scientists since they cannot reproduce on their own since they need a host to reproduce. The virus does hold its own genetic material, but it needs a post to pass it along. They can evolve but they lack several of the characteristics of life, therefore they cannot be classified as living
Covalent bonds vary depending on how equally electrons are shared
a) Nonpolar Covalent bond - atoms share electrons equally; the molecule is electrically balanced b) Polar Covalent bond - atoms share electrons unequally because one atom has a stronger attraction for the shared electrons; these bonds result in the molecule having partial charges
Describe the characteristics of life.
a) Organization - all living things are made of cells; multicellular organisms have biological organization, including the levels of tissues, organs, and organ systems b) Homeostasis - maintaining a regulated balance, including pH, temperature, water concentration, and other conditions c) Metabolism - using energy; includes all of the chemical reactions in living organisms, including photosynthesis and cellular respiration d) Reproduction- living things have offspring and pass on genetic material (DNA) to their offspring e) Growth and Development - living organisms have genetic material (DNA) that codes for growth (getting larger) and development (changing in shape or function) f) Response to Stimuli - living things respond to both internal and external stimuli, including eating when hungry (internal stimuli) or fleeing from danger (external stimuli); for example, plants also grow toward the external stimulus of sunlight) g) Evolution - the ability of a population to evolve over time h) ANSWERS TO HW QUESTIONS: i) Maintain homeostasis ii) Use energy iii) Made of cells iv) Grow and develop v) Respond to stimuli vi) Ability to reproduce
What is positive feedback? Give an example. Compare positive and negative feedback.
a) Positive Feedback - results in an intensified variable instead of counteracting it i) Example: When a human baby is being born (1) pressure causes release of hormones resulting in more contractions and more pressure (2) more pressure causes more release of hormones, resulting in more contractions and more pressure
Compare saturated and unsaturated fats. Give examples.
a) Saturated fats i) contain fatty acids with no double bonds between carbons (the fatty acid chains are therefore saturated with hydrogens) ii) the fatty acid chains are straight and can easily pack together iii) makes them solids at room temperature iv) usually made by Hydrogen (ex: butter, bacon fat) b) Unsaturated fats i) contain fatty acids with double bonds between the carbons ii) the fatty acid chains are bent/kinked and will not pack together tightly iii) makes them liquids at room temperature iv) usually made by Carbon (ex: olive oil, corn oil)
Describe the five major steps in the scientific method: observation; hypothesis; experiment; collect and analyze data; communicate findings
a) Scientific Method Example: You spend the day at the beach. After a couple hours, you notice your skin is bright red from a sunburn. You know you applied sunscreen, so you are curious as to why this has happened. b) Observation: i) Sunburn on face, shoulders and arms ii) SPF 5 sunscreen was applied iii) Outside for two hours c) Hypothesis: Expired sunscreen is less effective than up-to-date sunscreen. d) Prediction: Sunburn is a result of using expired sunscreen e) Experimentation: In an experiment you need to test the contribution of a single Variable to an Observation. (1) variable = Expiration date of sunscreen (2) observation = sunburn ii) Experiment: sunscreens with the same SPF with various expiration dates used at the beach. (1) Gather sunscreens with various expiration dates (2) Apply the sunscreens to different areas of your arm and proceed to the beach (3) Notice 2 hours later that all parts are sunburned. f) Conclusion (Analyze Data): Expired sunscreen is not the reason for the sunburn, yet different SPFs can contribute to the protection against the sun.
Water is a very important solvent. What dissolves in water? What does not dissolve in water?
a) Solvent - water can dissolve many other substances, especially polar molecules and ionic compounds (which contain charged ions) i) many body systems involve process that require water as a solvent ii) ex: kidneys could not function without water iii) ex: main component for body fluids is water b) Solutes are the substances that dissolve in a solvent, forming a solution. i) For example, salt is a solute that will dissolve in water to form saltwater. c) Hydrophilic substances have an affinity for water and readily dissolve in water; ex: NaCl, glucose d) Hydrophobic substances lack an affinity for water and separate from water; ex: fats and oils; Think of how "oil and water don't mix"
Consider the four main categories of organic compounds. Select the choices which correspond to these categories.
a. Carbohydrates b. Lipids
What four major types of biological molecules are required for all living things?
a. Carbohydrates b. lipids c. proteins d. nucleic acids
Describe the components of a negative feedback loop, including the following: stimulus, receptors, input, control center, output, effectors, response, return to set point.
a) The basic idea of a negative feedback loop: i) Variable (also known as a stimulus) - throws the body out of balance. ii) Body counteracts in response iii) Brings body back to homeostasis (ex: stable temperature) b) Components of the feedback loop: i) Stimulus (1) Disrupts homeostasis by increasing or decreasing a controlled condition that is monitored ii) Receptors (1) Monitor the environment and report perceived changes by sending input to control center iii) Input (1) Nerve impulses or chemical signals sent from receptors to control center iv) Control Center (1) Receives signal from receptor and formulates a response that provides output v) Output (1) Nerve impulses or chemical signals sent from control center to effectors vi) Effectors (1) Carry out the response from the control center, bringing about a change vii) Response (1) Alters the initial condition negative feedback minimizes/negates it; positive feedback enhances it) viii) Returns to Homeostasis Response brings controlled condition back to normal
What is negative feedback? Give examples
a) The simple definition of negative feedback is when a variable/stimulus triggers a counteracting response in order to come back to a set point. b) Negative Feedback is the primary way in which homeostasis is maintained: i) How does your body respond when you are out in the heat? (1) We sweat to cool down and moves to remove heat. Blood vessels are dilating to get rid of the heat, therefore we may become red. ii) How does your body respond when you are in the cold air conditioning? (1) We shiver which can generate heat and decrease our blood vessel diameter size to warm us up
Describe the unique properties of water
a) Water is a polar molecule because it has unequal sharing of electrons i) Oxygen atom is slightly negative ii) Hydrogen atoms are slightly positive
Solutes
a) are the substances that dissolve in a solvent, forming a solution. i) For example, salt is a solute that will dissolve in water to form saltwater.
Covalent bond
a) attraction between atoms where electrons are shared i) some atoms covalently bond with one other atom, some with many other atoms (1) ex: Proteins & DNA in our body (2) ex: methane (CH4) is a gas that has four H bonded to one C b) When atoms bond, only the outermost electrons furthest from the nucleus with the most energy are involved in bonding.
Iconic bond
a) attraction between oppositely charged ions i) one atom gives away one or more electrons to another atom (1) Sodium Chloride (table salt) is held together by ionic bonds
Polysaccharides
a) made up of many monosaccharides bonded together (often containing 1000's of sugar units) i) used for energy storage or to provide structure/building material for cells ii) Cellulose - most common structural compound in plants (1) Made of many glucose molecules bonded together (2) Most common organic compound on the planet! (3) Humans cannot digest cellulose à Cellulose is often referred to as fiber, which is important for proper digestion & "keeps things moving" through the intestines. iii) Starch (ex: amylose) - molecule plants use to store energy (1) Made of many glucose molecules bonded together iv) Glycogen - molecule animals use to store carbohydrate energy (1) Made of many glucose molecules bonded together (2) Stored in muscles and in the liver à if not used in about one day it gets depleted (3) Animals store energy long term in fat (which is a lipid NOT a carbohydrate)
Monosaccharides
a) simplest sugars made up of one (mono-) sugar (-saccharide) i) Glucose - fundamental sugar made by plants during photosynthesis ii) Fructose - significantly sweeter; found in fruits
Solvent
a) water can dissolve many other substances, especially polar molecules and ionic compounds (which contain charged ions) i) many body systems involve process that require water as a solvent ii) ex: kidneys could not function without water iii) ex: main component for body fluids is water
How do atoms relate to the study of life? Select the INCORRECT statement.
a. Atoms of different types are bonded within a single element
Which of the following is incorrectly described?
a. Control Center - receives input from effector and sends output to receptor
What is altruistic behavior? Select the examples which accurately demonstrates this type of behavior. (Select all that apply.)
a. Giving money to a wildlife conservation group b. Donating time and money to your community church
Select the INCORRECT statement when considering the purpose of the field of science known as taxonomy.
a. In taxonomy, organisms are grouped according to their country of origin.
Read each characteristic carefully and compare it to those in your notes. Some of these may be characteristics that SOME living organisms exhibit but not all.
a. Maintain homeostasis b. Use energy c. Made of cells d. Grow and develop e. Respond to stimuli f. Ability to reproduce
The Characteristics of Life
a. Organization b. Homeostasis c. Metabolism d. Reproduction e. Growth and Development f. Response to Stimuli g. Evolution
How do you display characteristics that indicate you are living? (select all correct responses)
a. Organizing your study notes for this biology class b. Taking an afternoon walk c. Adding rooms to your house as the family gets larger
What four elements are the most common in the human body?
a. Oxygen b. Hydrogen c. Carbon d. Nitrogen
Which of the following elements is INCORRECTLY matched with its symbol?
a. Sodium - S (It is actually Na)
Which of the following applies to proteins? (CHECK ALL THAT APPLY)
a. Some serve as enzymes b. Made up of amino acids c. Some are hormones d. Very diverse in structure and function
Why is it important to understand scientific information? (Select all correct choices.)
a. The more we know and understand what science tells us about the natural world, the better we are able to make responsible decisions based upon facts biases introduced by those with a profit incentive b. The more we know and understand what science tells us about the natural world, the better we are able to make responsible decisions based upon facts not emotions c. The more we know and understand what science tells us about the natural world, the better we are able to make responsible decisions based upon facts not political bias
Which are characteristics of DNA? Select all that apply.
a. The strands are oriented in an anti-parallel direction b. The hydrogen bonds almost always occur between A and T or G and C.
How will energy be extracted from a glucose molecule? Select all correct choices.
a. Through bond breakage b. Through exothermic reactions
Where does ATP store usable energy? Select all correct choices.
a. in the bond between the second and third phosphate b. in the bond between the first and second phosphate
How do the four levels of protein folding relate to one another? Choose the correct pairings.
a. quaternary structure is the covalent joining of several polypeptides b. primary structure is linear arrangement of amino acids
Select the INCORRECT role of carbohydrates, lipids or proteins in the body.
a. storage of genetic information
What makes an acid different from a base?
acids contain more hydrogen ions than hydroxide ions
Metabolism
using energy; includes all of the chemical reactions in living organisms, including photosynthesis and cellular respiration