Biology chapter 1 and 2

inference

inference

A logical interpretation based on prior knowledge and experience/what scientist already know.

Hypothesis

A testable prediction; suggested explanation

Steps of an experiment

Scientific Question, Hypothesis, Design Experiment, Results, Conclusion

Independent Variable (Manipulated Variable)

The experimental factor that is manipulated; the variable that you change. (x - axis)

Dependent Variable (Responding Variable)

the variable that is observed and that changes in response to the independent variable. What you measure. (y-axis)

controlled variable (constant)

A variable that is not changed

qualitative data

descriptive data, described with words

quanatative data

uses numbers to describe something

Casual Theory

hunch or prediction based on intuition, not facts

scientific theory

a well-tested concept that is supported by repeated testing and facts

scientific law

a rule that describes a pattern in nature/a natural phenomenon. Often mathematical.

cells

The smallest unit of an organism that can be considered alive - smallest unit of life.

sexual reproduction

type of reproduction in which cells from two parents unite to form the first cell of a new organism

asexual reproduction

process of reproduction involving a single parent that results in offspring that are genetically identical to the parent

DNA

A molecule/universal genetic code that determines the inherited traits of every organism on earth.

Metabolism

the combination of chemical reactions as it carries out its life processes. (Need to eat, excrete waste, exchange gases - humans)

Stimulus

a signal to which an organism responds

external stimuli

environment outside

internal stimuli

within an organism

Homostasis

the relatively constant internal physical and chemical conditions that organisms maintain

Response to stimuli

Living things adjust and respond to changes in their internal and external environments.

Characteristics of life

1. Made of cells

2. Ability to reproduce

3. DNA,

4. Growth & development

5. Responds to stimuli

6. Homeostasis

7. Metabolize

8. Evolve

evolve

To change over time; change based on environmental pressure

Grow and develop

To grow and mature, to be able to reproduce

atom

The basic unit of matter

Isotopes

Atoms of the same element that have different numbers of neutrons

Protons

Positively charged subatomic particles found in the nucleus of an atom

Nuetrons

Neutral subatomic particles that don't have a charge and located in an atoms nucleus

Electrons

negatively charged subatomic particles that orbit the nucleus - in the (shell/orbit/level)

Elements

One or more atoms but are the same type of atoms ; cannot be broken into simpler units by chemical reactions. ( example H2)

Compounds

2 or more different types of atoms chemically combined / bound together (example H2O)

Molecules

two or more atoms bound together, can be the same or different atom (example H2O & H2)

Ions

positively and negatively charged atoms

Anions

negatively charged ions

Cations

positively charged ions

valence shell

outermost shell of an atom

valence electrons

electrons in the outermost shell

Neutral atoms have

same number of protons and electrons

covelant bond

bond formed by the sharing of electrons between atoms

Hydrogen bonds

Weaker than Ionic and covalent bonds; Caused by the bonding of a partial positive charged hydrogen atom to a partial negative charged atom. Hydrogen bonds have the ability to attach and detach.

hydrogen bonds affect on water?

Since water is polar it can form many hydrogen bonds. hydrogen bonds are also responsible for water's cohesion and ability to dissolve many other substances. Since water expands upon freezing, it makes ice more dense than liquid water.

ionic bond

A chemical bond resulting from the attraction between oppositely charged ions.

ionic compound

A compound that consists of positive and negative ions

Water is -----

polar

polar

A molecule that has negative and positive sides

Cohesion

Attraction between molecules of the same substance

Adhesion

An attraction between molecules of different substances

water is a _____ bond

covalent

water has the highest _____

heat capacity

heat capacity

amount of energy needed to raise a substances temperature by making it's molecules move faster.

universal solvent

Water- due to its polarity and ability to dissolve many different solutes

Buffers

Most buffers consist of a weak acid and a weak base. They help maintain a given pH even after the addition of an acid or a base; help maintain homeostasis in organism

Marcomolecules

large organic molecules found in living things

monomers

small unit that can join together with other small units to form polymers

polymers

chains of monomers

monomers hook together using

dehydration synthesis (releasing water)

monomers unhook using

hydrolysis (taking in water)

Name the 4 macromolecules

carbohydrates, lipids, proteins, nucleic acids

Carbohydrates

the starches and sugars found in foods

Lipids

fats and oils; large, varied group of macromolecules that aren't generally soluble in water.

nucleic acids

DNA and RNA genetic codes

Protien

a class of nutrients that builds body tissues and supplies energy.

monomer of carbohydrates

monosaccharides (ex: glucose and fructose)

monomer of lipids

glycerol and fatty acids

monomer of nucleic acids

nucleotides made of 5 carbon sugar, a phosphate group, and a nitrogenous base

monomer of proteins

amino acids

polymer of carbohydrates

polysaccharide (ex: starch, cellulose, glycogen)

polymer of lipids

triglyceride and diglyceride

polymer of nucleic acids

polynucleotide (nucleic acid)

polymer of protein

polypeptide

function of carbohydrates

provide energy for all living things and for structural purposes.

function of lipids

long term energy storage; Important for the biological membrane and water proof coverings.

function of nucleic acids

store and transmit genetic or hereditary information

function of proteins

To control the rate of chemical reactions and regulates cell procedures. Important for structure and transporting cells to help fight diseases.

A protein is one or more ____________

folded polypeptide

Carbohydrates are made of

carbon, hydrogen, oxygen

Lipids are made of

carbon, hydrogen, oxygen

nucleic acids are made of

carbon, hydrogen, oxygen, nitrogen, phosphorus

Proteins are made of

carbon, hydrogen, oxygen, nitrogen

polyunsaturated fats

fat molecules that have more than one unsaturated carbon-carbon double bond in the molecule.

chemical reaction

a process that changes one set of chemicals into another set of chemicals.

reactant

a chemical substance that is present at the start of a chemical reaction.

product

element/compound produced as a result of a chemical reaction

catalyst

a substance that speeds up the rate of a chemical reaction; works by lowering reactions activation energy.

enzyme

A protein that acts as a biological catalyst - speeds up chemical reactions, lowers activation energy.

What property of the enzyme makes it specific to the substrate?

Enzymes are specific to substrates as they have an active site which only allow certain substrates to bind to the active site. This is due to the shape of the active site and any other substrates cannot bind to the active site.

How are saturated fats different from unsaturated fats?

Saturated fatty acids lack double bonds between the individual carbon atoms, while in unsaturated fatty acids there is at least one double bond in the fatty acid chain.

radioactive isotopes

isotopes with unstable nuclei and break down at a constant rate over time; Dangerous; can be used to detect cancer, kill bad bacteria in food, and can also be used as labels/tracers to follow the movements of substances within organisms.