Life Processes Exam 1

What is the smallest functional and structural unit of all living organisms

Cell

How do organisms break down food into nutrients

Metabolism

What’s the best way for an organism to maintain homeostasis

Humans sweat when they get hot to reduce body temperature

Scientific method

System to determine the truth about the way that the natural world works

Experimental variable

Variable being manipulated

What is a hypothesis?

Possible and testable explanation for a natural event

Control group is

Experimental group where experimental variable is held constant

Positively or negatively charged atom

Ion

Ability of water to attach itself to firm drops

Cohesión

Solution with a low pH

Acid

Covalent bond

Two atoms sharing a pair of electrons

Molecules that contain hydrogen and oxygen

Organic molecules

Atomic number

Describes number of protons in an atom

Which of the following properties of water is NOT due to hydrogen bonds

Water is amphoteric

What electrons are involved in bonding

Valence electrons

OH-

Are released when a base is added to water

what’s a pH of an acid

1-6

Buffer

Compound resistant to changes in pH when acid or base is added

Macromolecules are assembled by ____

Dehydration synthesis

All carbohydrates contain all of the following except

Nitrogen

What is a disaccharide?

Type of carbohydrates where two sugars are bound together

Characteristics of Life

Homeostasis

Organization

Acquire material and energy

Respond to stimuli

Grow and Increase Size and Number

Reproduction

Evolution

Organization Levels of Life

Atoms

Molecules

Cells

Tissue

Organ

Organ System

Organism

Atom

Smallest unit of an element

Cell

Smallest structural and functional unit of an organism

Tissue

Group of similar cells that perform a specific function

Organism

Individuals in a species that are made of a complex organ system

Metabolism

Sum of all chemical reactions that occur within a cell or organism

Homeostasis

Constant internal environment

Endothermic

Can generate and regulate their own body temp

Ectotherms

Can not generate or regulate their own body temperature

Heterotroph

An organism that can’t produce its own food and directly consumes its energy

Autotroph

Organism that can produce its own food

Voluntary Response

If cold put on a sweater

Involuntary (Autonimic)

Shivering when cold

DNA

Genetic info for life and directs the structure and function of the cell

Deoxyribose Sugar

Adenine to Thymine

Guanine to Cytosine

Phosphate

Double Helix

Genes

Short sequences of DNA that specify instructions for specific traits

Mutations

Minor variations in genes resulting from errors in DNA replication

Four Type of Mutations

Substitution

Deletion

Insertion

Inversion

Evolution

Process by which a population changes over time

Natural Selection

Mechanism by which evolution occurs

Adaptations

Mutations that provide a benefit to an organism survival or reproductive ability

What domain and Kingdom are humans apart of?

Domain Eukarya

Kingdom Animalia

Scientific Method Steps

Observation

Hypothesis

Experiment

Data or analysis

Conclusion

Observation

Formal way of watching the world

Hypothesis

Possible and testable explanation for a natural event

Experiment

Series of procedures to test hypothesis

Data

Findings of an experiment

Experimental Variable

Variable being manipulated

Responding Variable

Variable measured to determine if it changes in response to a change in the experimental variable

Control Group

Experimental group where the experimental variable is held constant

Element

Basic building block of matter that CANT be broken down by chemical means

Elements in the human body

Carbon

Nitrogen

Oxygen

Hydrogen

Atoms

Smallest unit of an element that still retains the chemical and physical properties of the element

Make Up of Elements

Protons

Neutrons

Electrons

True or False: Electrons and Protons are found within the nucleus

False: protons and neutrons are inside the nucleus and electrons are found outside

Atomic Mass

Sum of protons and neutrons in the nucleus

Isotopes

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

Radioisotopes

Unstable isotopes that release various types of energy in the form of rays (radiation) or subatomic particles

Molecules

Two atoms of the same element bonded together

Compounds

Two atoms of different elements bonded together

Ions

Positively or negatively charged atoms or particles

Ionic Bond

Attraction between two equally and opposite charged particles where one atom donates an electron to another atom

Covalent Bond

Atoms sharing an electron between their valence shell

Strongest bond

Hydrogen Bonds

Attraction between water molecules created by polarity

Weakest bond

Polar Covalent Bond

Unevenly shared electrons creating a double covalent bond

Nonpolar covalent bond

Equally shared electrons

Properties of Water

High Heat Capacity

High Heat of Evaporation

Polar

Solvent

Cohesive

Adhesive

Polar

One negative and two positive ends

Acids

Release hydrogen H + ions in water

PH scale is 0 to 6

Bases

Substances that absorb hydrogen ions and release hydroxide ions into water

Ph 8 to 14

Amphoteric

Substance that is both an acid and a base

Buffer

Compound that resists changes to ph when an acid or base is added to it because it is amphoteric

Organic Molecule

Molecules containing carbon and hydrogen

Macromolecules

Molecules that contain many subunits

Four types of macromolecules

Carbohydrates

Lipids

Proteins

Nucleic Acid

Dehydration Synthesis

Builds macromolecules by connecting the subunits directly by removing the hydrogen bonds when removing water molecules

Hydrolysis

Breaks down macromolecules by adding water between the subunits

Carbohydrates

Universal energy source

Contain carbon hydrogen and oxygen

Carbohydrates subunit

Monosaccharide

Disaccharide

Polysaccharide

Monosaccharide

Simple CHO

One sugar molecule

Example: glucose

Disaccharide

Simple CHO

Two sugar molecules joined together by dehydration reaction

Example maltose and sucrose

Polysaccharide

Complex CHO

Three or more sugar molecules joined together by dehydration reaction

Example starch and glycogen

Starch

How plants store glucose

Glycogen

How animals store glucose

Cellulose

Polysaccharide that plants use for structure of cell wall that we are unable to digest

Lipids

Fats and oils that do not dissolve in water

Lipid Subunits

Triglyceride

Phospholipids

Steroids

Triglycerides

Made of glycerol and three fatty acids

Fats and oils

Fats

Animal based and solid at room temperature

Oils

Plant based and liquid at room temperature

Emulsification

Chemicals that surround an oil droplet so that the oils polar end projects outward allowing it to mix with water

Fatty Acid

Carbon hydrogen chain that ends with an acid group like COOH

Saturated Fatty Acid

No double bond between the carbons completely filled with hydrogen bonds

Solids like butter

Unsaturated fatty acids

Double bond between the carbons wherever there are less than 2 hydrogen bonds

Oils

Unsaturated trans fatty acid

Some double bonds with hydrogens on opposite sides of the carbon

Man made

Hydrogenated oils

Phospholipids

Lipids made of fatty acids and phosphate group

Hydrophylic polar head

Hydrophobic nonpolar tail

Primary component of plasma membrane

Makes up phospholipid bilayer

Steroids

Lipids with a backbone of four fused carbon rings

Large molecules

Make up sex hormones

Regulate the immune system

Proteins

Made of amino acids

Contain carbon hydrogen oxygen and nitrogen

Functions of proteins

Offer support

Enzymes

Transport

Defense

Hormones

Motion