biol121 - week 1

chemical level

atoms are the smallest chemical units of matter (small particle)

molecules: a group of atoms working together

elements: substance that is made up of only one type of atom

all living orgamisms are made up of chemicals

proteins

diverse & have a variety of roles, insulin and growth hormones, enzymes that help all of the metabolic reactions occur in the body, structural proteins

largely responsible for structure of body tissues, enzymes

carbs

example: glucose - source of energy to create ATP, some can have structural or messaging roles

lipids/fats

energy storage and structural role: cell membrane is created with lipid - fatty acid, triglycerides, phospholipids

nucleic acids

building blocks of DNA, inherited genetic material - DNA & RNA

functions: structure, storage, messengers, control

cellular level

a group of atoms, molecules and organelles working together - cell membrane, nucleus, structure is related to their function

basic unit of life, living structural, functional unit of the living body, units that are doing the jobs to contribute to homeostasis

three main parts: plasma, cytoplasm & nucleus

tissue level

a group of similar cells working together

organ level

two or more tissues working together with a common purpose = organ

an organ: a group of different tissues working together

organ system level

• group of organs working together

• series of tubes to deliver blood to the organs, deliver nutrients, pick up wastes and remove them

• we have 11 organ systems

• control/direct, cool and warm, digest, move, protect, remove, reproduce, store, support and transport

body cavities

spaces that inclose internal organs, fully inclosed sacs,

organs are suspended within these body cavities

separated by bones, muscles, ligaments and membranes

function: protect (fluid by membrane tissue that surronds them - protects from shocks and impacts), seperate and support internal organs

contract and relax - requires changes in shape and movement - body cavities allows them to do this,, without distorting or changing surrounding tissue and disrupting activity

thoracic & abdominopelvic: are separated by the diaphragm

anatomical position

standing erect, head level and eyes facing forward, hangs at side and palms forward, legs parallel and feet flat on the floor

anterior

towards the front

posterior

towards the back

cranial

towards the head

cadudal

towards the tail

above

superior

below

inferior

away from the midline

lateral

medial

towards the midline

proximal

closer to the point of attachment

distal

futher to the point of attachment

superficial

closer to the surface

deep

futher from the surface

periodic table

• each element has own name and chemical symbol

• horizontal = period and vertical = groups

• in groups - similar proprieties - group 0 are noble gases

atoms cont.

mall central nucleus made up of smaller sub-atomic particle - protons and neutrons. nucleus is surrounded by even smaller particles called electrons

protons (positive) and electrons (negative): electrical charge and neutrons are neutral

electrons

in an atom are arranged in energy levels - orbits or shells, each electron are found in a particular shell

innermost shell - lowest energy level fills with electrons first

each shell can only hold a certain amount until it becomes full

first = 2, other shells = 8

outmost = valance - these electrons can participate in the formation of chemical bonds with other atoms, so chemical reactions involve the rearrangement of electrons in the outermost shell

molecules and compounds

molecule: two or more atoms joined together by chemical bonds

can be an element or compound - when atoms from two or more different elements react/bond together (h20)

some atoms are unlikely to react with other atoms - single atoms & have a stable electron substance because outer shell is full

other atoms react and bond together to become stable

• elements form compounds in chemical reactions

• atoms have fixed ratios & held together by chemical bonds

ion

an atom or molecule with a net electric charge due to the loss or gain of one or more electrons

• atoms can loose or gain electrons from their outer shell - when they do they form charged particles called ions

ions cont

when atoms lose electrons they form positively charged ions known as cations. When atoms gain electrons to form negatively charged ions known as anions. - these are attracted to each other due to being opposite

• during ionic bonds - electrons are transferred between atoms, leaving some with fewer electrons and others with more electrons

organic compounds

all contain the elements carbon and hydrogen

• carbs, lipids, proteins and nucleic acids = small biological molecules & large biological molecules and polymers

• usually lack carbon - cant be used by cells to peform complicated biological functions

inorganic compunds

not made up of living things, they usually dont contain the element carbon (besides carbon dioxide and monoxide)

• water and salts (contains ions)

• when inorganic acids, bases or salts in water - they seperate into ions and are surrounded by water molecules

acidic

• the more H+ dissolved in a solution, the more acidic solution and the LOWER the pH

basic

the more more OH dissolved in a solution, the more basic solution and the HIGHER the pH

neutral

hydrogen ions = hydroxide ions

distilled water

when the H+ ions from an acid react with the OH– ions from an alkali, a neutralisation reaction occurs to form water. ****

plasma membrane function

• physical barrier, separated ICF and ECF

• very different in ICF AND ECF and this maintains homeostasis

• gatekeeper - controls the entry and nutrients, elimination of wastes and release of secretions = determines movements in and out of cells

• communication with cells and organs by receptors

• maintaining homeostasis is vital for cell and organisms

• links adjacent cells - specialises connections between cells and membranes - gives tissues stability

plasma membrane function

phospholipid: basic structure

• hydrophilic phosphate heads - at membrane surface, in contact with aqueous environment

• hydrophobic tails - on the inside, wont associate with water molecules

proteins (peripheral - bound to outer surface of the membrane or integral - span the membrane, if removed = membrane would be destroyed)

• channels, gates or pumps = transport - by passing the hydrophobic tails

• carrier proteins

• receptors

• anchoring

selective permeability

due to the structure of the membrane and lipid bilayer, it lets some substances in.out and stops others due to solubility, size, and charge

• water souble molecule: transport chanell because it doesn’t want to interact with hydrophobic fatty acid tails

• small fat-souble: directly passes through

• small charged ion: ion channel, as it’s charged

epithelial

covers exposes surfaces, lines internal passage ways and chambers and forms glands, all substances must pass through if leaving body

• protection, absorption, filtration, exertion, secretion

• exposed to external surfaces

• classified by shape (second name) and number of layers (first name)

simple layers: transport

multiple: protection

• outer layer of the skin, lining of intenstine

connective

supports

• supports and binds other tissues

• structural framework

• storing energy

• protecting delicate organs and defending them from invading organisms

• provides insulation and protection

• extra-cellular matrix - heaps

• amount of cells present - less

classified according to physical properties

• connective tissue proper: fat, tendons, ligaments,

• fluid connective tissue: blood and lymph

• supporting connective tissue: blood and bone

= dermis of skin

= bone, blood & fat cells

= ligaments and tendons

muscle

moves

specialised for contraction to facilitate movement

capable of contribution

joint stability, provides structural control and produces heat

• skeletal, smooth, cardiac

• very well organised - heaps of cells

nervous

controls

main component of nervous system, which regulates and controls body functions

• primary function is communication

• two basic cells: neurons - electrical impulses (nerve cells), neurogila (support cells - repairs and supplies nutrients to neurons)

contenous membrane

skin, covers the entire body surface, organ system attached to epithelium, exposed to air and is a dry membrane - protection

mucous membrane

line all body cavities that upon to the outside of the body - digestive, respiratory, urainary and reproductive tracts - coated with the secretions of mucous glands, prevents organs from drying out and protects from microbes - adaptive for absorption and secretion

serous membrane

line body cavities closed to the exterior of the body (organ within cavities, and aren't directly open to exterior), secrete lubricating fluid

synonvial membrane

synovial: line joint cavities and produce fluid within the joint, lacks an epitelium and only connective tissue

diffusion

the net movement of a molecule from an area of high concentration to low

osmosis

he movement of water molecules across a semi-pearbale membrane from an area of low solute concentration to high solute concentration

active transport

the movement of an ion or molecule from an area of lower concentration to an area of high concentration, via a channel or carrier protein, against a concentration gradient

hyPERtonic

have a higher concentration of soultes compared to what is inside the cell - the cell looses water via osmosis and shrives - cell dehydration (crenation)

hyPOtonic

have a lowe solute concentration, gain water via osmosis and swell - most extremed example = distilled water , bursts (lysis)

isotonic

have same solute water concentration as inside of the cell - same amount of water leaving and entering - cells retain normal shape

homeostasis

maintenance of normal physiological parameters within the body

the body’s ability to maintain a stable and balanced internal environment

• detects when something is out of balance, processes this information and bring about changes that will restore this balance

• this equilibrium is required to keep us alive

feedback systems

controlled condition (variables that is monitored - temp) & stimulus (any disruption to the controlled condition)

receptor (eg: nerve ending):: detects the change and notifies the control centre

control centre (eg: brain) sets the range upper and lower limits of the controlled condition, receives info from the receptor, evaluates and processes, thus determines which action to take, send outputs commands

effector: receives commands from the control centre and produces the response

RESPONSE: effect that changes the controlled condition

when restored - receptor stop picking up messages/change, control centre can switch off commands, effector stop doing the response

negative feedback

negative feedback: the response OPPOSES the initial stimulus to reverse the change

responses work in the opposite direction to the stimuli

negative feedback does not refer to the absolute direction of the response

• most homeostasis mechanisms are negative feedback system

• something that is going up, to go back down & etc

• conditions that need frequent adjustments

• body temp, blood sugar levels, blood pressure, blood calcium levels, blood pH

positive feedback

• strengths or enhances the stimulus to produce an even great/amplified change

• LARGE & RAPID change

• release of oxytocin during childbirth and breast feeding, formation of the platelet, activation of immune cells

integumentary

skin, hair, nails, sweat glands -dermatology

protection, sensation and thermoregulation

nervous

brain, spinal cord, nerves , PNS - neuro & cerebro'

control communication, regulation of other body systems

endocrine

glands - hormone

secretion of hormones to regulate other body systems

skeletal

bone, cartlige - osteo, chondro

provides structure and protection, controls and supports movement, production of blood cells in bone marrow

muscular

muscles - smooth, cardaic, skletal

movements of the skeleton

cardiovascular

cardio, vaso, erythocyce (RBC), lympatic

transport 02, deliver blood, distribution of nutrients and wastes

respiratory

lungs - bronch, pulmno

gas exchange

immune

lymphatic, organs, vessels, bone marrow - lymphocyte

defence against pathogens

urinary

kidneys, bladder, urainary track - renal

excrete wastes, regulation of blood volume

reproductive

ovaraities, testies, gentalalia - oocyte, spermatocyte

reproduction

digestive

stomach, small intestine, mouth, gall bladder, liver

digesting, absorption's of nutrients