Biology - Unit 1: Into To Biology

Growth

cellular reproduction

development

variation in cells

reproduction

the production of offspring- asexual or sexual

what is the relationship between structure and function

structure enables function

how are organisms classified

based on genetic similarities

ecology

study of relationship of organism to environment

food web

interrelated food chains

food chains

diagram to show how energy passes through the ecosystem

symbiosis

relationship between two organisms that live closely

parasitism

symbiotic relationship in which one organism benefits and the other is harmed

mutualism

symbiotic relationship in which both organisms benefit

commencalism

symbiotic relationship in which one organism benefits and the other is neither harmed nor helped

evolution

the change of species over time

natural selection

an individual that has a better trait to survive in it's environment will survive and pass the trait to it's offspring

characteristics of living things

all living things are made of cells, are organized at cellular and molecular levels, obtain and use materials and energy, maintain stable internal conditions, grow and develop, reproduce, respond to their environment, and change over time

are viruses full cells

no

examples of living things made of cells

unicellular and multicellular

subatomic particles

neutron proton electron

Levels of cellular organization

atoms, molecules, cells, tissues, organs, organ system, organism

what do living things use energy for

to fuel metabolism

metabolism

the sum of all chemical reactions in an organism

autotroph

organism that makes it's own food

heterotroph

organism that cannot make it's own food

homeostasis

maintaining stable internal conditions

asexual reproduction

no exchange of genetic material. offspring is identical to parent.

sexual reproduction

exchange of genetic material. offspring is diverse.

stimulus

a change in environment to which an organism responds

response

a reaction to a stimulus

scientific method

a process of solving a problem that is observed in nature

controlled experiment

experiment in which one variable is changed and is based off a comparison of control and experimental groups

can there be more than one experimental group in an experiment

yes

independent variable

the factor being manipulated. there is only one of these in an experiment

dependent variabl

what is being measured in an experiment

control

a condition without the independent variable

steps of scientific method

identify problem, background research, hypothesis. test hypothesis with experiment, analyze data, draw conclusions, make an evidence based claim, justify claim with data from the scientific community, communicate results

how to title a graph

dependent variable vs independent variable, always use units, y axis is dependent variable and x axis is independent variable

inference

an observation based on data, not direct observation

modeling

a representation of an idea, object, or process that cannot be directly experienced

theory

a well accepted explanation for a wide range of observations

examples of theories

evolution, atomic theory, big bang, cellular theory

can theories change

yes, in the event that future evidence provides a better explanation

why is peer review important

It allows researchers to share ideas and to test and evaluate each other's work.

name 3 important bonds

ionic, covalent, hydrogen

ionic bonds

one atom gives away an electron. makes positively and negatively charged ions. atoms are joined together due to oppositely charged ions.

covalent bonds

sharing electrons. biologically strongest bond. covalent bonds are called molecules

what are the only electrons that can bond

valence electrons

which electrons have the most energy

valence electrons

molecules

groups of atoms that share atoms covalently

Ionic bonds

when an atom gives away an electron and the two are joined together due to opposite charges

examples of covalent bonds

h2o, glucose, dna linear strands

Hydrogen Bonds

link molecules by the weak bonds formed by polar molecules

How do hydrogen bonds work

big atoms pull electrons away from smaller atoms in a molecule, so the molecule becomes slightly polar and oppositely charged sides of molecules bond.

examples of hydrogen bonds

water and dna

what makes up 60% of our bodies

water

why is water a good solvent

it is polar. when polar or ionic compounds are added to water they dissociate or dissolve

what is cohesion

when water molecules make hydrogen bonds with other water

what does cohesion create

surface tension

What is the significance of cohesion

it creates a high heat capacity and high specific heat and a high heat of vaporization

what is specific heat

the amount of heat that can be absorbed before temperature rises

Adhesion

polar molecules stick to other polar molecules

Cappilary action

when water moves upward against gravity through tiny pores

properties of water

cohesion, adhesion, high specific heat, polar

mixture

A combination of two or more substances that are not chemically combined

types of mixture

solution, suspension, colloid

solution

homogeneous mixture where one substance is totally dissolved in another

solvent

the substance in which the solute dissolves

solute

the substance that is dissolved

concentration

how much solute to solvent

examples of solution

plasma, urine, saliva

suspension

heterogeneous mixture in which the particle size of one substance is large so it settles out

examples of suspensions

pulpy orange juice, salad dressing, blood

colloid

homogeneous mixture in which one substance of large particle size is totally dissolves in another

examples of colloids

milk, cytoplasm

acids

substances that form hydrogen ions or hydronium (H+) when dissolved in water

physical properties of acids

sour, burning feeling

biological acid examples

stomach acid, fruit juice

bases

substances that form hydroxide (OH-) ions in water

physical properties of bases

bitter, slippery, burn skin

examples of bases

coffee, dark chocolate, saliva, intestinal secretions

what are bases referred to as

alkaline

ph scale

scale for measuring relative concentration of hydrogen ions and hydroxide ions in a solution

ph scale range

0-14

acid range ph scale

0.1-6.9

base range ph scale

7.1-14

how is the ph scale used in biology

homeostasis - bodies require narrow range of ph to function properly

buffers

substances that minimize changes in pH

why is ph important for protein function

proteins work best at certain ph

what type of bonds hold the atoms of a water molecule together

covalent

what causes water to be polar

oxygen is bigger than hydrogen so it pulls electrons towards oxygen

describe hydrogen bonding between water molecules

polar molecules are attracted to each other because opposites attract

what does ph measure

the percentage of hydrogen in a substance

ph formula

ph=-log{H+}

what ph is neutral

7

what is a ph greater than 7

base

what is ph less than 7

acid

when h+ is increased what happens to ph

it goes down

when h+ is decreased what happens to ph

it goes up

how many times more acidic is a ph of 3 than a ph of 4

10

which molecule in water molecules pulls electrons towards it

oxygen

which molecule in water are electrons pulled away from

hydrogen