Final exam 1 Biology CH 1,2,3, and 5

what is science?

a process of gaining knowledge through evidence and logic

which of the following is an example of a scientific law?

Medel’s law of inheritance

scientific theory

a broad explanation supported by extensive evidence

first step in the scientific method

making an observation

in an experiment, the variable that is measured is called the

dependent variable

a control group is an experiment is important because it

used for comparison to the experimental group

which of the following is a limitation of science?

it cannot answer questions about supernatural events

replication is science refers to

repeating an investigation to verify results

which of the following is NOT a characteristic of all living things?

ability to photosynthesize

homeostasis refers to

maintaining a stable internal environment

the basic unit of life is the

cell

which level of biological organization includes all living and non-living components in an area?

ecosystem

binomial nomenclature gives each species

a unique two word Latin name

the most inclusive taxonomic rank is

domain

which domain contains organisms with a nucleus?

Eukarya

humans are classified in the kingdom

animalia

the four most common elements in the human body are

carbon, hydrogen, oxygen, and nitrogen

an atom that has gained or lost electrons is called

an ion

a covalent bond involves

sharing of electrons

water is a polar molecule because

oxygen is more electronegative than hydrogen

which property of water allows it to resist temp changes?

high heat capacity

a pH of 4 is considered

acidic

buffers are important because they

prevent changes is pH

the monomer of a carbohydrate is

monosaccharide

cellulose is a polysaccharide that

provides structural support in plants

a saturated fatty acid

has no double bonds

phospholipids are important because they

form cell membranes

the primary structure of a protein refers to

the sequence of amino acids

denaturation of protein results from

extreme heat or pH

which nucleic acid is single stranded

RNA

ATP stores energy in

the bonds between phosphates

enzymes function by

lowering activation energy

the cell theory states that

all living things are made if cells

cell remain small because

their surface area to volume ratio limits size

which organelle is the site of protein synthesis?

ribosome

The plasma membrane is composed mainly of:

phospholipids and proteins

facilitated diffusion

uses protein channels

in a hypertension solution, a red blood cell will

shrink

active transport requires

ATP

which organelle is responsible for cellular respiration?

mitochondrion

the endomembrane system includes all EXCEPT

mitochondria

cilia and flagella are composed of

Microtubules

tight junctions function to

create a barrier between cells

glycolysis occurs in the

cytoplasm

the electron transport chain is located in the

inner mitochondrial membrane

fermentation occurs when

oxygen is absent

The ATP-ADP cycle involves

adding/removing phosphate groups

phagocytosis is a type of

endocytosis

which of the following is a function of the cytoskeleton?

maintaining cell shape

ribosomes can be found

attached to the ER or free in cytoplasm

in a double blind experiment

neither subjects nor researchers know who is in the treatment group

qualitative data refers to

descriptive observations

metabolism includes

both building up and breaking down molecules

which taxonomic rank is more specific than class but more general than family?

order

a dehydration synthesis reaction

joins monomers into polymers by removing water

a nucleotide consists of

sugar, phosphate, and nitrogenous base

the fluid mosaic model describes

the dynamic nature of the plasma membrane

which organelle modifies and packages proteins for secretion?

Golgi apparatus

explain the role of hydrogen bonds in the properties of water

hydrogen bonds give water its unique properties: cohesion, high heat capacity, and solvent ability.

• water molecules are polar (oxygen is slightly negative, hydrogen slightly positive)

• hydrogen bonds form between the positive H of one molecule and the negative O of another

• Leads: cohesion, high heat capacity, solvent ability, ice floats

describe the processes by which the organic molecules are assembled and disassembled

assembled via dehydration synthesis; disassembled via hydrolysis

• dehydration synthesis: removes a water molecule (OH from one monomer, H from another)

• hydrolysis: adds a water molecule (breaks bonds) splits polymers into monomers

summarize the basic chemical properties of a carbohydrate

carbohydrates are made of C,H,O in a 1:2:1 ratio, polar and hydrophilic

• functions primarily as energy sources and structural components

state the roles of carbohydrates in human physiology

energy source, energy storage, and structural roles

explanation: immediate energy, short-term storage, structural, and dietary fiber

compare the structures of simple and complex carbohydrates

simple= 1-2 sugar units; complex= long Chinas of sugars

simple carbs

monosaccharides (glucose, fructose) and disaccharides (sucrose lactose)

• quick energy, easily digested

complex carbs

polysaccharides (starch, glycogen, cellulose)

• long chains of glucose; slower to digest, provide sustained energy/structure

state the function of each class of lipids

fats/oils: long term energy storage, insulation, cushioning

phospholipids: form cell membranes (create bilayer barrier)

steroids: act as hormones (testosterones, estrogen) and stabilize membranes

waxes: protections and waterproofing

1. Intermediate filament

2. Ribosome

3. Rough endoplamic reticulum

4. Nucleus

5. Nucleolus

6. Chromatin

7. Golgi apparatus

8. Golgi vesicles

9. Cytoplasm

1. Mitochondria

2. Plasma membrane

3. Microtuble

4. Centrosome

5. Micro filament

6. Lysome

7. Smooth endoplasmic reticulum

8. Secretory vesicle

9. Preoxisome

10. Vacole

describe the structure of an amino acid

central carbon bonded to: amino group, carboxyl group, hydrogen, and R-group

Anabolism

Building up something

Catabolism

Breaking down something

Mitochondria

performs cellular respiration

plasma membrane

made of phospholipids that surrounds the cell and it’s help form the shape of the cell

lysosome

contains enzymes to break down molecules

smooth endoplasmic reticulum and rough endoplasmic reticulum

smooth: lacks ribosomes synthesize lipids

rough: contains ribosomes (that’s why its rough) helps process and transport proteins

cytoplasm

watery substance called cytosol and contains other cell structures like ribosomes

Golgi apparatus

modify proteins and lipids (helps process and package)

nucleolus and nucleus

nucleolus: contains the DNA

nucleus: contains DNA and directs protein synthesis

ribosomes

makes the protein

describe the structure of an atom

it has a nucleus with proteins and neutrons with electrons orbiting on the valence shell(outer shell).

atomic number= number of protons

mass number= protons + neutrons

difference between ionic and covalent bonds

ionic: donate and take electrons. and it forms between metal and nonmetal (positive attracts negative)

covalent: sharing electrons. forms between nonmetal

• polar covalent: unequal sharing

• non-polar: equal sharing

explain the role of hydrogen bonds in the properties of water

• gives water "high heat capacity= resists temp changes

• gives water high heat of vaporization= cooling through sweat

• cause cohesion(water sticking to it’s self)

• adhesion (water sticking to other surfaces)

summarize the pH and the importance of buffers to biological systems

pH measures H+ concentration

0= acidic

7=neutral

16=basic

buffers= resists pH changes by absorbing excess H+ or OH-

what are the 4 class of organic molecules found in cells

carbohydrates(quick energy), lipids(fats/oils), proteins(enzymes, structure), and nucleic acids(ATP is the energy coin)

describe the process by which the organic molecules are assembled and disassembled

assembled: from monomers through dehydration synthesis, removing a water molecule to form a bond

disassembled: back into monomers through hydrolysis, reaction adds water molecule to break a bond

summarize the basic chemical properties of a carbohydrate

basic units are monosaccharides (sugar rings) they are polar due to hydroxyl (-OH) can polymerize by dehydration reactions to form disaccharides and polysaccharides

state the role of carbohydrates in human physiology

two roles

1. immediate energy source and primarily forms glucose

2. short term energy source in the form of glycogen in the liver and muscles

compare structures of fats, phospholipids, and steroids

1. fats: triglycerides one glycerol and three fatty acids

2. phospholipids: two part structure polar phosphate head and two fatty acid tails

3. steroids: different structure four fused carbon rings and lack fatty acids

function of each class of lipids

fats/oils: function energy storage, insulation, cushioning

phospholipids: components of cellular membranes

steroids: messengers and membrane stuff

structure of an amino acid

its a monomer of protein. each has a central carbon atom bonded to it

explain how amino acids are combines to form proteins

are combined to form proteins through dehydration synthesis which forms bonds between amino acids

state the basic principles of the cell theory

1. cell is the basic unit of life

2. all living things are made up of cells

3. new cells arise from pre-existing cells

explain the surface area of volume ratio limits cell size

are small because its volume increases

small= harder for nutrients to enter and waste to exit

distinguish between the structure of a prokaryotic cell and eukaryotic cell

prokaryotic: lack a nucleus, lacks membrane organelles

eukaryotic: has a nucleus, membrane bound organelles, DNA in the nucleus

how eukaryotic cells evolved from prokaryotic cells

prokaryotic cells was engulfed by a bigger cell and established symbiotic relationship. the mitochondria has their own DNA and was able to reproduce independently

describe the structure of the plasma membrane and list the type of molecules found in the membrane.

structure= fluid mosaic(phospholipid bilayer) where proteins move freely and hydrophobic tails face inward

• molecules found: phospholipids, proteins, cholesterols, glycoproteins and glycolipids