bio test 3

all animals cells have similarities in the ways in which they:

exchange materials with surroundings(plasma membrane), obtain energy from organic nutrients, synthesize complex molecules (glycogen), reproduce themselves, detect and respond to signals in immediate environment (responsiveness), lack cell walls

levels of organization

cellular- phylum porifera

tissue- phylum Cnidaria and ctenophora

organ- phylum platyhelminthes

organ systems- advanced animal groups (vertebrates)

internal organization

cells with similar properties and group to form tissues, tissues combine together to form organs, organs are linked to form organs systems

tissues

an association of many cells that have similar structure and function

what are the four types of tissues

epithelial, muscle, connective, nervous

epithelial tissues

sheets of densely packed cells that: cover the body or enclose organs and line the walls of body cavities and organs

epithelial tissues function

specialized to protect and secrete/absorb ions and organic molecules

what shapes are the epithelial tissues

cuboidal, squamous, columnar

simple, stratified, and pseudistratified epithelial tissues

simple- one layer that secretes and absorbs

stratified- multiple layers that protect

pseudostratified- one layer but appears stratified

types of epithelial tissues

simple squamous- single layer flat

simple cuboidal- single layer square

simple columnar- single layer rectangle

pseudostratified columar- 1 cell thick with all attached at basement layer

stratified squamous- multilayer flat (skin)

connective tissues

connect, surround, anchor, bind, transport, and support; form extracellular matrix around cells

function of connective tissues

provide scaffold for attachment (muscle to bone), protect and cushion, mechanical strength (ligaments and tendons), transmit information (plasma)

types of connective tissues

blood- transport and protect

adipose- insulation (fat), energy, support and protect

bone- hardened and support and protect

cartilage- support and flexible (between joints)

loose- hold internal organs in place (loose attachment to body wall)

dense- strength and support (tendons and ligaments)

muscle tissues

cells specialized to contract and generating mechanical force

types of muscle tissue

skeletal, smooth, cardiac

skeletal muscle

attached to bone or exoskeleton for locomotion, elongate fiber, voluntary control

smooth muscle

surrounds tubes and cavities for propulsion of contents, flat cells, involuntary control (nervous)

cardiac muscle

found only in the heart, branched fibers, involuntary control

nervous tissue

complex networks of neurons (nerve cells and others)

functions of nervous tissue

initiate and conduct electrical signals from one part of an animals body to another

electrical signals produced in one neuron may stimulate or inhibit other neurons to:

initiate new electrical signals, stimulate muscle cells to contract, stimulate glandular cells to release chemicals also contain neuroglial cells, provide metabolic support and maintence and ion balance and cleaning, produce new glial cells and neurons

organs

composed of two or more kinds of tissues, may form sheets, tubes, layers, bundles, or strips

organ system

different organs work together to perform an overall function, these system work together, play a part in the overall body plan

what controls the body plan

highly conserved family of genes with homologs in all animals (hox genes) especially vertebrates which have the most cluster

structure and function of an organism

organization of structure (form) usually can predict the function of structure, increasing complexity of structure to increase complex function and emphasis on vertebrate function

homeostasis

process of adjusting to the external environment and maintaining a stable internal environment; changing variables in the environment: air temperature, water temperature, food supply, water supply, pH, O2 concentration in water especially; body will make changes to get normal state; slight differences (imbalance) are normal; more complicated organizms is harder and takes longer

integumentary system

the ineguement and its derivatives

functions of integumentary system

protection from abrasion, protects against water loss, barrier to disease causing pathogens, protection from UV light, temperature regulation (sweat), contains sensory receptors (touch), limited excretion (evaporative cooling)

integument

skin and all other accessories (hair and feathers)

skin

largest organ of vertebrates, consists of 2 layers: epidermis is outer and dermis is inner

epidermis

thinner outer layer, nutrients diffuse from dermis (no blood), stratified squamous epithelium (primary), lots of dead cells

integumentary cell types

langer Hans cells- defensive

melanocytes- pigment melanin, skin color, protect UV light

Merkel cells- touch receptors (advanced in mammals)

keratinocytes- primary, keratin, increase from in to out, fill cytoplasm then die

dermis

thicker and inner layer, highly vascular (blood vessels), contains vessels and nerves and glands (sensory), origin of hair and feathers and scales, meissner’s corpuscles - light touch, Pacinian corpuscles- deep pressure and vibration

sweat glands

temperature regulation, 2.5 million in human, produces sweat (water), release heat

sebaceous glands

all over body except for palms of hands and soles, large on face and neck and upper chest, produce sebum

hypodermis

subqutaneous layer, beneath dermis, not skin layer, lots of fat tissue, females have thicker adipose layer (softer skin)

functions of hypodermis

body contour, insulated supports skin, energy skin, hold in heat

nutrient

any substance taken in by an organism that is needed for survival and growth and development and maintenance or reproduction

nutrition

process of consuming and using food and nutrients

heterotrophic

cant make own food, require already synthesized organic compounds

in heterotrophs organic compounds of plants or other animals to supply for:

survival, maintence, growth, reproduction, more food intake, more energy (ATP)

gut tract

blind gut and tube with in a tube

blind gut

no cavity between gut and body wall, one opening and primitive

tube with in a tube

flow through digestive tube, body cavity between gut and BW, separate openings (mostly), advanced form

digestive enzymes

hydrolases, require water, carbohydrates, lipases, proteases, nucleases

food processing

ingestion, digestion, transport, absorption, egestion

ingestion

food taken into body and move to alimentary canal

digestion

food broken down into smaller molecules, chemical and mechanical

absorption

ions and water and small molecules diffuse into circulatory system (nutrients and vitamins and hormones)

egestion

undigested materials and other wastes (eliminate)

alimentary canal

digestive tract, elongated tube open on each end, smooth muscle in the walls, lined by simple epithelial cells

in the alimentary canal what does the lining of epithelial cells do

synthesize and secreted digestive enzymes, secrete hormones, transport materials

structure if GI tract

some general structure from midpoint of esophagus to the anus, lumen lined by epithelial and glandular cells, secretory cells release protective layer of mucus, other cells release hormones, gland cells release acid and enzymes and water and ions

region of reception

buccal cavity- mouth and associates, ingestion site and digestion (mechanical and chemical), jaws and teeth and cheek muscles and tongue and salivary glands (saliva- amylase), pharynx- back of mouth cavity and the point that digestive and respiratory system cross paths

region of conduction

esphogus- tube carrying materials from mouth to rest, conducts food from pharynx to stomach, peristalsis- rhythmic wave like contraction with smooth muscle that propel food down the GI tract

region of storage and more digestion

stomach (mostly), sac-like organ evolved to store food, muscular nature to help break up food and partial protein digest, regulate rate of emptying into SI, secrets HCl - kill microbes and dissolve particulate matter and pepsinogen- converted pepsin to begin protein digestion, epithelium coated with alkaline mucus

region of terminal digestion and absorption

small intestine, nearly all digestion and absorbtion (99.5%), hydrolytic enzymes found on apical surface of epithelial cells or secrete by pancreas into lumen, products of digestion are absorbed across epithelial cells and enter the blood, length is 8x height, most absorption

if food is not digested or broken down in the small intestine will it be digested

no

surface area specializations

small intestine specialized to carry out the bulk of digestion and absorption, mucosal infolding, villi- finger like projections, increase SA by 600 fold, increases likelihood of food particle encountering digestive enzyme and being absorbed

3 regions of the small intestine

duodenum- receive lots of secretion into here, jejunum and ileum- absorb

plicae circulares

large folds of epithelial lining and increase surface area 2-3 times

villi

finger like projections, increase surface area 10 x, lined with simple epithelium

microvilli

folding of the plasma membrane of cells lining the villi, increase surface area 20 x

region of water absorption and concentrated solid

conserve water and package waste, large intestine, mammals- about 1.5 meters, no plicae villi or microvilli, water absorbs through the epithelium

function of the large intestine

human absorb about 1400 mL of water per day, compacts and elimate feces

components of waste

75% water, 5% inorganic substances- broken down but not absorbed, 8% roughage- no absorb, 5% fat, 2% undigested protein and dead cells and bile

anus

opening at posterior end of the alimentary canal for release of waste material, cloaca- chamber of recieving contents of digestive repro and urinary tract

accessory digestive glands

not part of alimentary canal, salivary gland, pancreas, liver, gall bladder

salivary gland

necessary for proper digestion and absorption

pancreas

secrete enzymatic juices through the pancreatic duct into the duodenum

liver

produces bile that assists enzymes in the break down of large fat globules into smaller forms

gall bladder

storage of bile- secrete into SI if needed with increased fat

biomolecules

carbohydrates, proteins, fats, nucleic acids, enzymatic activity for chemical reactions at biological temperatures that weaken the bond enough to be broken down

carbohydrates

polysaccharides- mono and disaccharides, starch or glycogen- fructose and glucose and sucrose

proteins

polypeptides convert to amino acid by the pepsin bond breaking

fats

glycerol and fatty acids

nucleic acids

dna and rna into nucleotides or the individual subunit

nervous system

central nervous system is the brain and spinal cord, peripheral nervous system is all neurons and projections outside of the CNS, in some invertebrates with simple the distinction is less clear, mammals have complex peripheral nervous system

cellular components of nervous system

neurons- nerve and glia- support

neurons

send and receive electrical and chemical signals to and from each other and other cells throughout the body, structural and functional units of NS, present in all animals except sponges, varies widely as function of size and behavior complex

neuron structure

cell body or soma, dendrites, axon; typically occur in bundles wrapped around by connective tissue called neurons

cell body or soma

has nucleus and organelles

dendrites

extension of cells body, single and branched, receive signal

axon

extension of cells body, single and carry signal to other cells, away from cell body, length depend on complexity, branches wrapped in myelin sheath (coating)

axon hillock

base and near cell body

axon terminals

tips convey signals to other cells

glia

surround neurons and perform various functions, 1000x more numerous than neurons, astrocytes, microglia, oligodendrocytes, Schwann cells, radial glial cells

astrocytes

metabolic support, maintain stable concentration of ions in extracellular fluid

microglia

participate in immune functions, remove cellular debris

oligodendrocytes and Schwann cells

produce myelin sheath interrupted by non insulated nodes of Ranvier

radial glial cells

can produce all other neurons, including itself

sensory neurons

detect information from outside or internal body conditions= afferent

motor neurons

send signals away from CNS to get response, efferent

interneurons

form interconnections, small cell body, critical inpretation of information and get response

reflex arc

stimulus from sensory neurons to CNS, little to no interpretation, transmitted to motor neurons to elicit response, quick and automatic response

electrical properties of neurons

membrane potential- gate keeper of channels and its the membranes discretion, only neurons and muscle cells generate electrical signals, cell is polarized due to membranes permeability, difference in ions between inside and outside the neuron, causes both chemical and electrical differences, imbalances (slight) are normal, chemicals or electrical charge never equal they are just small

resting membrane potential

when neuron not sending a signal, selectively permeable to cations and anions, polarity is inside more negative and outside more positive and vice versa because of attraction between charges, can be movement if membrane lets channels open up for a short time, the closer the ion is to the membrane the quicker and ion can diffuse in or out

electro-chemical gradient

imbalance due to difference inside and outside of neuron, charge with chemical either positive or negative, positive charge gates, chemicals- K+, Na+, Cl-

three factors affecting resting potential

sodium- potassium pump, ion specific channels allow passive movement (more permeable to K and open more frequently open at resting), polarity- more negative inside neuron

sodium potassium pump

atp spent and pump 3 Na+ for every 2K+