midterm study guide freshman

cell

smallest unit of life

stimulus

anything that causes you to react

homeostasis

a state of balance among all the body systems needed for the body to survive and function together

metabolism

the chemical changes that takes place in a cell or an organism

repreoduction

the production of offspring

asexual reproduction

one parent copies itself to form a genetically identical offspring

sexual reproduction

an organism combines the genetic information from each of its parents and is genetically unique

evolution

the change in the characteristics of a species over time and relies on the process of natural selection

unicellular

one cell

multicellular

multiple cells

characteristics of life

reproduction, organization, adaption, growth and development, DNA, energy, homeostasis, evolution

example of metabolism

building glucose from carbon dioxide

abiotic

non living things

biotic

living things

biosphere

all life on earth

ecosystem

all the living and nonliving things that interact in an area

community

different populations that live together in a defined area

population

a group of organisms of the same species populating a given area

organism

any living thing

species

taxonomic group whose members interbreed

producers

organisms that can make their own food

consumers

an organism that cannot produce its own food and must eat other plants and/or animals to get energy

herbivores

eats plants

carnovers

eats animals

omnivers

eats both

decomposers

**organisms that break down wastes and dead organisms and return raw materials to the environment**

parasitism

one species benefits, the other is harmed

commensalism

one species benefits, the other doesn’t but isn’t harmed

mutualism

both species benifit

fossil fuels

non-renewable energy sources

10% rule

10 percent of the energy stored as biomass in a trophic level is passed from one level to the next

natality

birth

competition

interaction in which two or more species use the same limited resource

mortality

death

emigration

leaving one's own country to settle permanently in another; moving abroad

immigration

the action of coming to live permanently in a foreign country

invasive species

species that enter new ecosystems and multiply, harming native species and their habitats

nitrogen fixing

the chemical processes by which atmospheric nitrogen is assimilated into organic compounds

predator

hunts for food

prey

caught for food

primary consumer

herbivores

secondary consumers

carnivors

transpiration

the exhalation of water vapor through the stomata

trophic level

organism in a food chain that represents a feeding step in the passage of energy and materials through an ecosystem

carbon cycle

nitrogen gas is changed into forms of nitrogen that plants can use

water cycle

the path that all water follows as it moves around Earth in different states

biotic factors

animals, plants, fungi, bacteria, and protists

abiotic factors

water, air, soil, sunlight, and minerals

molecule

a group of atoms bonded together

polar

electrons are not shared evenly over the covalent bond

hydrogen bond

slightly positive hydrogen on one molecule is attracted to a slightly negative atom in another molecule

organic molecule

molecules that contain carbon

active site

where the substrate combines with the enzymes

substrate

molecule that gets helped by an enzyme

6 most abundant elements

carbon, nitrogen, oxygen, phosphorus, hydrogen, sulfur

structure of water

negative oxygen and positive hydrogen

carbohydrates monomer

monosaccharide

carbohydrates purpose

provide body with glucose

carbohydrates examples

glycogen, photosynthesis

carbohydrates structure

carbon, hydrogen, oxygen

lipids structure

fatty compounds

lipids monomer

glycerol and fatty acids

lipids purpose

storing energy

lipids examples

cholesterol, phospholipids

nucleic acids structure

nucleotides

nucleic acids monomer

nucleotide

nucleic acids purpose

pass on genetic information

nucleic acids examples

DNA and RNA

protein structure

amino acids linked together

protein monomer

amino acids

proteins purpose

enzymes, transport, messengers, movement

protein example

muscles

job of enzyme

speed up chemical reactions

situations that affect enzyme rate

temperature, pH, enzyme concentration, substrate concentration

pH levels related to acids

pHs less then 7

pH levels related to bases

pHs greater then 7

digestive system purpose

break down food molecules into smaller monomers so the body can use the nutrients

teeth function

tear food into smaller pieces

saliva function

moistens food, contains enzymes which break down starches into simple sugars

function of esophagus

tube connecting throat to stomach

function of stomach

site of mechanical and chemical digestion

function of liver

creates bile

function of small intestine

digestion, a place for the circulatory to absorb nutrients, passes along remaining undigested food

function of large intestine

removes water

order of organs food passes through

mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum

chemical digestion

complex molecules like proteins, fats, and carbohydrates are broken down into smaller pieces that your body can use

mechanical digestion

physically breaking down food substances into smaller particles to more efficiently undergo chemical digestion

where carbohydrates are digested

mouth, small intestine, pancreas

where proteins are digested

the small intestine, pancreas

where lipids are digested

small intestine, with help from liver and pancreas

cell membrane job

provides protection for a cell

cell membrane structure

a lipid bilayer

nucleus function

stores the DNA

nucleus structure

includes nuclear membrane, chromosomes, nucleoplasm, and nucleolus

nucleolus structure

RNA and proteins

nucleolus function

produce and assemble the cells ribosomes

nuclear envelope function

separates the nucleus from the cytoplasm and provides the structure for the nucleus

mitochondria

creates energy in the form of ATP

ribosomes location

attached to the er and scattered throughout the cytoplasm

ribosomes function

making protein through amino acids