Bio Midterm

What are the steps in the scientific method?

1. Observing and asking questions
2. Making inferences and forming hypotheses
3. Conducting controlled experiments
4. Collecting and analyzing data
5. Drawing conclusions

What makes a good hypothesis?

specific and testable

Define theory

well-tested explanation that unifies a broad range of observations

Define bias

A particular preference or point of view that is personal, rather than scientific.

Define homeostasis

Helps the body maintain a stable internal environment

What is the basic unit of length in the metric system?

meter

Define mass number

the total number of protons and neutrons in an atom

How do you calculate mass number?

number of protons + number of neutrons

What is an isotope?

atoms with the same number of protons but different number of neutrons

Define compound in terms of physical and chemical properties

What kinds of electrons form bonds?

valence electrons

What is the difference between ionic bonds and covalent bonds?

ionic bonds are transferred while covalent bonds are shared

What is an ionic bond?

A chemical bond that's formed when an atom transfers and electron to another Atom

What is a covalent bond?

A chemical bond formed when two or atoms share electrons.

What makes water molecules polar?

A water molecule has a slight charge on each end.

Define acid on the pH scale

1-6 on the pH scale

Define base on the pH scale

8-14 on the pH scale

What are the unique qualities of carbon?

Carbon has 4 valence electrons which allows it to form strong covalent bonds with many other elements, it can form 4 covalent bonds, it can form chains, can form large complex structures

What are the elements of carbohydrates?

carbon, hydrogen, oxygen

Examples of macromolecules

carbohydrates, lipids, proteins, nucleic acids

What are the elements of lipids?

carbon, hydrogen, oxygen

What are the elements of proteins?

carbon, hydrogen, oxygen, nitrogen

What are the elements of nucleic acid?

carbon, hydrogen, oxygen, nitrogen, phosphorus

What is the monomer of carbohydrates?

monosaccharides (simple sugars)

What is the monomer of lipids?

glycerol and fatty acids

What is the monomer of proteins?

amino acids (20 different ones)

What is the monomer of nucleic acid?

nucleotide (sugar, phosphate, nitrogen base)

What is the function of carbohydrates?

provide energy

What type of bond is between monomers in carbohydrates?

What is the function of lipids?

store energy

What type of bond is between monomers in lipids?

What is the function of proteins?

growth and repair

What type of bond is between monomers in proteins?

What is the function of nucleic acid?

store and transmit genetic information

What type of bond is between monomers in nucleic acid?

What macromolecule makes up the majority of the cell membrane?

What is a phospolipid?

a lipid that has a phosphate group attached to the glycerol and only 2 fatty acids

What parts of a phospholipid are hydrophilic?

head

What parts of a phospholipid are hydrophobic?

tail (fatty acid chains)

What does semi-permeable mean?

allowing certain substances to pass through it but not others

What bond does a dipeptide have?

What is a monosaccharide?

single sugar molecule

What is a disaccharide?

two monosaccharides (simple sugar molecules) joined together

What is a polysccharide?

Many simple sugars joined together

Define activation energy

energy needed to start a chemical reaction

What is the function of an enzyme in a chemical reaction?

Define ecology

the study of relationships between living organisms and between organisms and their environment

List of the groups that make up the organization of ecosystems in the correct order

organism, population, community, ecosystem, biome, biosphere

Primary producers in an ecosystem

what is a synonym for producer?

autotroph

what is a synonym for consumer?

heterotroph

How do primary producers make their own food?

using light energy (photosynthesis) to make carbohydrates or chemical energy

What do herbivores and carnivores have in common?

They are both consumers

What is a food chain?

A series of steps in which organisms transfer energy by eating and being eaten

What is a food web?

network of complex interactions formed by the feeding relationships among the various organisms in an ecosystem

Define omnivore

An organism that eats both plants and animals

Define carnivore

an animal that gets its energy by eating other animals

Define herbivore

an animal that gets its energy by eating plants

Define detritivore

An organism that feeds on and breaks down dead plant or animal matter.

Define scavenger

animal that feeds on the remains of other organisms. Examples are vulture, black bear, beetle

Define decomposer

an organism, especially a soil bacterium, fungus, or invertebrate, that decomposes organic material.

Define trophic level

represent a feeding step in the transfer of energy and matter in an ecosystem.

What is the percentage of energy passed from one trophic level to the next?

10 percent

biotic factors and examples

All the living organisms that inhabit an environment, bears, fish, trees

abiotic factors

Nonliving components of environment, rocks, air

What is at the base of all ecological pyramids?

producers/autotrophs

What is an organisms niche?

all the biotic and abiotic resources it uses

competitive exclusion principle

principle that states that no two species can occupy the same niche in the same habitat at the same time

Parasitism

A relationship between two organisms of different species where one benefits and the other is harmed

Commensalism

A relationship between two organisms in which one organism benefits and the other is unaffected

Mutualism

A relationship between two species in which both species benefit

primary succession

succession that occurs on surfaces where no soil exists, volcano

secondary succession

Succession following a disturbance that destroys a community without destroying the soil, hurricane, faster than primary succession

freshwater ecosystems

lake, river, swamp, marsh, bog

Why are estuaries important?

Estuaries serve as spawning and nursery grounds for many ecologically and commercially important fish and shellfish species including bluefish, striped bass, shrimp, and crabs.

What is a population's geographic range?

What four factors play a role in a populations growth rate

exponential growth

growth whose rate becomes ever more rapid in proportion to the growing total number or size.

logistic growth

Growth pattern in which a population's growth rate slows or stops following a period of exponential growth

What is carrying capacity?

the number of people, other living organisms, or crops that a region can support without environmental degradation.

What is a limiting factor?

factor that causes population growth to decrease

What is the function of DNA?

store and transmit genetic information

What are the base pairs in DNA?

Adenine, Thymine, Guanine, Cytosine

What is Chargaff's rule?

A=T and G=C

What are the three parts of a nucleotide?

sugar, phosphate, nitrogen base

What did Watson and Crick discover?

double helix structure of DNA

What did Rosalind Franklin discover?

that DNA is in the shape of a Helix through her use of X-ray diffraction

What is the end result of DNA replication?

Two identical strands of DNA

During DNA replication, a DNA strand that has the bases GATCCA produces a strand with what base sequence?

What is the function of DNA polymerase in DNA replication?

What is the difference between dna and rna?

DNA is double stranded and RNA is single stranded, they contain different sugars

Who is credited with naming cells?

Robert Hooke

What did Leeuwenhoek discover?

bacteria

What did Schwann discover?

animals are made of cells

What did Scleiden discover?

What did Virchow discover?

All cells come from other cells

What are the principles of the cell theory?

Cells are the basic units of life.
All living things are made of cells.
All cells are produced from existing cells.

What is the difference between prokaryotes and eukaryotes?

Prokaryotes don´t have a nucleus or membrane bound organelles and Eurkaryotes do

Prokaryote

A unicellular organism that lacks a nucleus and membrane bound organelles

Eukaryote

A cell that contains a nucleus and membrane bound organelles