BIO 238 Lecture

Homeostasis

(KEEPING INTERNAL CONDITIONS STABLE) - homeostasis: the ability of an organism to maintain consistent internal environment, or "steady state", in response to changing internal or external conditions

Receptors

(a component of the homeostatic system) - body structure that detects change in a variable (stimulus) - typically consist of sensory neurons

Control Center

(a component of the homeostatic system) - structure that both interprets input from receptors and initiates changes through the effector

Effectors

(a component of the homeostatic system) - structure that brings about the change to alter - muscles and exocrine glands are often the effectors

Integumentary System

(hair, skin, nails) -provides protection -regulates body temperature -*synthesizes vitamin D -prevents water loss

Four main categories of tissues :

- Epithelial tissue: covers exposed surface and lines body cavities. (the edge/border) - Connective tissue: protects, supports, and binds structures and organs - Muscle tissue: produces movement - Nervous tissue: conducts nerve impulses for communication

Urinary System

- Filters the blood to remove waste - concentrates waste products in the form of urine - expels urine from the body

Water :

- Inorganic molecule ( no carbon on it) - exhibits polarity - unequal sharing of electrons between the oxygen and the two hydrogen atoms - oxygen atom is more electronegative - one water molecule can form four hydrogen bonds with adjustment water molecules

Subatomic particles of an atom include :

- Neutrons = no charge - Protons = + charge - Electrons = - charge

High Specific Heat

- amount of energy (in cals) required to increase the temperature of 1 gram of a a substance by degree Celsius - water has one of the highest specific heat values - because you need energy to break the hydrogen bonds between molecules

Endocrine System

- consist of glads and cell clusters that secrete hormones - maintain homeostasis of blood composition and volume, digestive processes, and control reproductive function

Cardiovascular System

- consist of the heart and blood vessels - moves blood through vessels in order to distribute hormones, nutrients, gases, and pick up waste products

Heat of Vaporization

- energy required for release of molecules from a liquid phase to a gas phase for 1 gram of substance - water has a high heat of vaporization -because you have to break the hydrogen bond first to release the water molecules into the gaseous state

Hydrogen bond

- forms between polar molecules - attraction between a partially positive atom of one polar molecule with a partially negative atom of a second polar molecule

Digestive System

- mechanically and chemically digests food - absorbs nutrients - expels waste products

- Nonpolar covalent bonds: - Polar covalent bonds:

- nonpolar covalent bonds: both atoms in the bond have an EQUAL attraction for electrons - Polar covalent bonds: atoms in the bond share electrons UNEQUALLY

Skeletal System

- provides supports and protection - site of hemopoisis(blood cell production) -*stores calcium and phosphorus site for ligament and muscle attachment

Nervous System

- regulatory system that controls muscles and some glands - helps control all other body systems - responsible for consciousness, intelligence, and memory

Respiratory System

- responsible for exchange of gasses between blood and the air in the lungs

The periodic table is organized into:

- rows based on atomic number - columns based on the number in the outer shell ( also known as the VALENCE SHELL)

Transports

- substance dissolves in the water and moves through the body in water-based fluids (step 1 of the functions of water in the body)

Lymphatic System

- transports and filters lymph (interstitial fluid) - may participate in an immune response

When salt (NaCI) is placed in water :

- water molecules' partial Negative charge interact with the Cation(Na+) - water molecules' partial Positive charge interact with the Anion(CI-)

Muscular System

-produces body movement -generates heat when muscles contract

1st (innermost) shell can hold up to_______ electrons

2 ((this is when you are diagramming atomic structures))

Only _____ elements occur in living organisms in greater than trace amounts

8

All subsequent shells have a capacity of at least _____ electrons

8 (( this is when diagramming atomic structures))

A complete outer shell results in:

Chemically Stability (noble gases) - exhibit low reactivity do not usually combine with other elements

Tissue Level

Consist of molecules, (which are groups of similar cells that perform common functions)

Organ System Level

Contains multiple related organs that work together to coordinate activities and achieve a common functions

Organismal Level

Highest level of structural organization in the body

An organism must be able to adjust internal bodily function in response to environmental changes, this is called :

Homeostasis (regulation)

A process called ______________ _____________ happens in which hydrogen bonds between water molecules "force out" non-polar molecules

Hydrophobic Exclusion

Reproductive System (female and males)

MALE: - produces sperm and testosterone - transfers sperm to female reproductive tract FEMALE: - produces oocytes (eggs), estrogen, and progesterone - site of fertilization -site of growth of embryo and fetus - production and secretion of breast milk

Atoms that lack a full outer shell with eight electrons tend to lose, gain, share electrons to obtain a complete outer shell. This is called ?

Octet Rule

The more electronegative atom develops a

Partial Negative charge

The atoms with the stronger electronegativity

Pulls the shared electrons closer to its nucleus

Atomic Number

The number of PROTONS in an atom of that element

Base:

a substance that accepts when added to a solution. - Decreases the concentration of H+ that are FREE in a solution - because bases remove free H+ from a solution it is called Proton Acceptor -Stronger bases Bind More that do weal bases, leaving less H+ in solution

Acid :

a substance that dissociates on water to produce both an H+ and an anion. - increase the concentration of H+ that are FREE in a solution - because H+ of a proton, an acid is also called a Proton Donor - stronger acids dissociate to a greater extent and produce More H+

Matter

a substance that has mass and occupies space - all matter is composed of atoms

Solvent:

a substance that is able to dissolve solutes ( sugar, salt, oxygen etc.)

The pH of a solution is measures by the relative :

amounts of H+ it contains - expressed by a number between 0-14

Atoms

are the smallest particle that exhibits the chemical properties of an element

Chemically Bond:

associates between two or more elements

Adhesion:

attraction between water molecules and a substance other than water

Amphipathic molecules have :

both polar and non-polar regions

The effectors:

causes the change (or effect)

Organ Level

composed of organs, which contain two or more tissue types that work together to perform specific, complex functions

Cellular Level

consist of cells, (which are the smallest living structures), and serves as the basic unit of structure and functions in organisms.

Molecules:

contain atoms of only 1 element ( ex: O2)

Atoms can also reach chemical stability by sharing electrons resulting in a :

covalent bonds

Gross anatomy

deals with structures that can be seen with the naked eye

Microscopic anatomy

deals with structures too small to be seen with the naked eye

All organisms exhibit responsiveness, which is the ability to ______ and ______ to stimuli

detect, react

A receptor:

detects the stimulus

Polar and ions both do what within water ?

disperse or dissolve (this is called Hydrophillic)

Acids and bases do what in water

dissolve and dissociate

Amphipathic molecules do not completely ...

dissolve in water, - that polar portion dissolves in water - the non-polar is repelled by water and grouped together - this process forms a Plasma Membrane on a cell

Non-polar molecules

do not dissolve in water ( this is called Hydrophobic)

Hydration shell forms around ....

each ion

Positively charged cations and negatively anions may bind together by:

electrostatic interactions called iconic bonds

Atoms share electrons in a covalent bonds either :

equally or unequally between that atoms

The variable ___________ around the set point over time

fluctuates

The elements in column VIIIA each have a valence shell that is :

full

Physiology is the ___________ of the body parts

functions

All organisms produce new cells for :

growth, maintenance, repair, and reproduction

Following a climatic event, the body again returns to ______, when we are in positive stimulus

homeostasis

Water molecules surround each polar molecule and form a __________ ________ around it. The polar molecules _______ _________ as they are surrounded

hydration shell, remain intact

Ions:

individual atoms or groups of atoms that have a positive or negative charge

The Control Center:

integrates input information and initiates output to the effectors

Surface Tension:

inward pulling of cohesive forces at the surface of water - occurs because water molecules at the surface are pulled by hydrogen bonds on only 3 directions

Homeostasis:

is restored

A stimulus:

is the change in variable

Chemical Symbol

is unique to each element

The sum of all chemical reactions that occur within the body is called :

metabolism

Compounds:

molecules that contain atoms for more than 1 element (ex: H2O)

Most processes in the body are controlled by

negative feedback

The electrons shells closest to the _________ must be filled ________

nucleus, first (( this is when diagramming atomic structures))

The resulting action will always be in the ________, direction of the stimulus

opposite

The less electronegative atom develops a

partial positive charge

When the stimulus is ___________ it continues in the same direction until a climatic event occurs

positive

Cabolism

process of larger molecules broken down into smaller molecules (C= catastrophe, break things)

Anabolism

process of smaller molecules JOINED to form larger ones ( A= add, molecules being added/joined)

As a result of the hydration shell forming around each ion, salt does not _______ _______ when placed in water, but __________

remain intact, dissociates

The variable is maintained within a normal level, or what is called its _________

set point

Chemical Level

simplest level, includes atoms and molecules

Anatomy is the study of ___________ and ____________ of organisms.

structure, form

All organisms exhibit a complex _______ and ________

structure, order

The number of neutrons can be determined by :

subtracting the atomic number from the atomic mass

An Ion can have a negative charge from :

the GAIN of one or more electrons (also called Anions)

An ion can have a positive charge from :

the LOSS of one or more electrons ( called Cations)

The number of protons equals :

the atomic number

The number of electrons also equals also equals :

the atomic number (all atoms are neutral)

Cushions

the force of sudden body movements is absorbed by water-based fluids(step3)

Atomic Mass

the mass of BOTH protons and neutrons in the atomic nucleus

Excretes wastes

unwanted substances leaves the body dissolved in water(step4)

Cohesion:

water molecules "stick together" because of the hydrogen bonds between the molecules

Lubricates

water-based fluids between body structures decrease friction(step2)

Intermolecular attractions:

weak chemical attractions between TWO molecules