BIO EXAM 3

What phylum has cellular level of organization?

What phylum has cellular level of organization?

Phylum Porifea (sponges)

What phylum has tissue level of organization?

Phylum Cnidaria and Phlyum Ctenophora (2 jellyfish phyla)

What phylum has organ level of organization?

Phylum Platyhelminthes (flatworms)

Organ system level of organization

Advanced animal groups (vertebrates)

What are the 4 types of tissues?

1. Epithelial

2. Muscle

3. Nervous

4. Connective

What are the functions of epithelial tissues?

Sheets of densely packed cells that:

• cover the body or enclose organs

• line the walls of body cavities and organs

• specialized to protect and secrete/absorb ions and organic molecules

All epithelial tissues are considered what?

Asymmetrical or polarized

• one side rests on the basal laminate (basment membrane) and the other faces the environment

What type of tissue lines the nasal passage?

pseudostratified ciliated columnar

What type of tissue lines kidney tubules?

simple cuboidal

What type of tissue lines the urinary system?

transitional

What type of tissue lines the intestines?

simple columnar

What type of tissue lines the lungs?

simple squamous

Wha type of tissue lines the esophagus?

stratified squamous

What are all the types of epithelial tissues?

Simple Squamous

Simple Columnar

Simple Cuboidal

Stratified Squamous

Pseudostratified Columnar

Transitional

Connective Tissues

• connect, surround, anchor, bind, transport, support

• form the extracellular matrix (ECM) around cells

  • provides scaffold for attachment

  • protects and cushions

  • mechanical strength

  • transmit information

What are all the types of connective tissues?

• blood

• adipose (fat)

• bone

• cartilage

• loose

  • dense

Muscle Tissues

cells specialized to contract (shorten), generating mechanical force

What are the types of muscle tissue?

• skeletal

• cardiac

• smooth

Nervous Tissues

• complex networks of neurons (nerve cells) and other cells

• initiate and conduct electical signals from one part of the animals body to another

• electrical signals produced ion one neuron may stimulate or inhibit other neurons to

  • initiate new electrical signals

  • stimulate muscle clles to contract

  • stimulate glandular cells to release chemicals

What are the functions of neuroglial cells?

• provide metabolic support, maintenance, ion balance, and cleaning for the neurons

  • produce new glial cells and neurons

Homeostasis

process of adjusting to the external environment and maintaining a stable internal environment

What is the function of the vertebrate integument?

• protects from abrasion

• protects against water loss

• barrier to disease causing pathogens

• protection from U.V. light

• temperature regulation

• contains sensory receptors

• excretion (limited)

Epidermis

• mostly dead cells

• outer layer

• thinner

• nutrients diffuse into epidermis from the dermis

What type of epithelium makes up the epidermis?

stratified squamous

What are the 4 cell types in the epidermis?

Langerhan Cells

Melanocytes

Markell Cells

Keratinocytes

Langerhan Cells

defensive cells against pathogens

Melanocytes

• produce pigment melanin

• skin coloration

• protection from U.V. light

Markell Cells

touch receptors

Keratinocytes (epidermis)

• primary cell type

• produce insoluble protein, keratin

• amount of keratin increases from inside to outside

• keratin fills cytoplasm and impairs nutrient diffusion … cells die

Dermis

• living cells

• inner layer of skin; thicker than epidermis

• highly vascularized (vessels)

• contains sensory structures, vessels, nerves, glands

• origin of hair, feathers, scales of vertebrates

What are the two sensory structures found in the dermis?

• meisner’s corpuscles

• pacinian corpuscles

Meissner’s Corpuscles

light touch

Pacinian Corpuscles

deep pressure and vibration

Functions of the sweat glands

• temperature regulation

• produce sweat (primarily water)

• release of heat

• 2.5 million within body

Where are sweat glands found?

within the dermis

Hypodermis

• lies beneath dermis

• NOT a layer of skin

• contains much adipose (fat) tissue

What is the function of the hypodermis?

body contour and insulation

supports skin layer under skin

What are the two types of gut tracts?

• blind gut

• tube within a tube

Blind gut tract

• no cavity between gut and body wall

• one opening

• primitive form

Tube within a tube

• flow through digestive tube

• body cavity between gut and body wall

• separate openings (advanced)

What are all the digestive enzymes?

• carbohydrases (carbohdyrates)

• proteases (proteins)

• lipases (lipids and fats)

• nucleates (nucleic acids)

Food processing in animals happens in what 5 phases?

1. ingestion

2. digestion

3. transport

4. absorption

5. egestion

Alimentary Canal

• single elongated tube with an opening at both ends

• contains smooth muscle in walls

• lined by epithelial cells

  • synthesize and secrete digestive enzymes (simple epithelium)

  • secrete hormones

  • transport digested materials

• several specialized regions

Neurons in the GI tract are activated how?

• neurons activated by sight and smell of food, presence of food in tract

Region of Reception

• buccal cavity (mouth and accessory structures)

• ingestion site and digestion site (chemical and mechnical)

• jaws, teeth, cheek muscles, tongue, salivary glands

• pharynx: back of mouth cavity and the point that digestive and respiratory systems cross paths

Region of Conduction

• esophagus: tube carrying materials from mouth cavity to rest of the alimentary canal

  • neck region

  • through chest

• conducts food from pharynx to stomach

  • peristalsis: rhythmic, wave like contractions which propel food forward in GI tract (smooth muscle)

Region of storage and more digestion

• stomach (mostly)

• muscular nature of stomach helps break up food; partial protein digestion

• stomach regulates emptying into small intestine

What does the stomach secrete?

• hydrochloric acid: kills microbes, dissolves particulate matter (parietal cells)

• pepsinogen: converted into pepsin to help begin protein digestion (chief cells)

Region of Terminal digestion and absorption

• small intestine

• nearly all digestion of food and nearly all absorption of food and water

• hydrolytic enzymes found on apical surface of epithelial cells or secreted by pancreas into lumen

• products of digestion absorbed across epithelial cells and enter blood

  • vitamins, minerals, and water also absorbed

What are the 3 regions of the small intestine?

1. Duodenum

2. Jejunum

3. Ileum

What are the 3 surface area specializations exhibited by the small intestine?

1. Plicae Circulares

2. Villi

3. Microvilli

Plicae Circulares

• large folds of the epithelial lining

  • increase surface are 2-3 times

Villus (Villi)

• finger like projections

  • increase surface area 10 times

Microvilli

• folding of the plasma membrane of cells lining the villus

  • increase surface area 20 times

Region of H2O absorption and concentration of solids

• large intestine

• mammals: about 1.5 meters

• lack plicae, villi, mircovilli

• H2O absorbed thorugh epithelium

What accessory digestive glands are NOT apart of the alimentary canal but are apart of the digestive system?

• pancreas

• liver

• gall bladder

• salivary glands

pancreas

secrete enzymatic juices through the pancreatic duct into the duodenum of the small intestine

liver

produces bile (assists enzymes in breakdown of large fat globules into small forms)

gallbladder

storage of bile (secrete bile into small intestine as needed)

salivary glands

secretes saliva

Central nervous system

brain and nerve cord

Peripheral nervous system

all neurons and their projections that are outside of the CNS

Nervous systems have two classes of cells which are?

• neurons

• glia (glial) cells

What is the function of neurons?

send and receive electrical and chemical signals to and from each other and other cells throughout the body

3 structures of the neuron

• cell body or soma

• dendrites

• axon

cell body or soma

• contains nucleus and organelles

• processes incoming signals and generates outgoing signals

dendrites

• extensions of cell body, single or branching

• receive incoming electrical and chemical messages form other neurons

axon

• extension of cell body

• carries signal to other cells

• typically single, varies widely in length

• may have branches and be wrapped in sheath of myelin

axon terminals

make contact with nearby cells and transmit signals to them

What are the 3 main types of neurons?

1. Sensory Neurons (brain and spinal cord)

2. Motor Neurons

3. Interneurons

Sensory Neurons (brain and spinal cord)

• detect information from the outside world of internal body conditions

• also called afferent neurons: transmit to CNS

Motor Neurons

• send signals away from CNS

• efferent neurons to elicit response

Inteneurons

• form interconnections between other neurons

• critical in interpretation of info and elicited response

What are the 5 types of glial cells?

1. Astrocytes

2. Microglia

3. Oligodendrocytes (CNS)

4. Schwann Cells (PNS)

5. Radial glial cells

Reflex

• stimulus form sensory neurons sent to CNS, little or no interpretation (few or no interneurons), signal transmitted to motor neurons to elicit response

• quick and automatic response

ONLY what types of cells generate electrical signals?

• neurons

• muscle cells

Why are neurons polarized?

cell is polarized due to membranes permeability

What are the 3 factors contibruting to resting potential?

1. Sodium-Potassium Pump

2. Ion specific channels allow passive ion movement

3. Polarity

How is speed of nerve impulse rate related in invertebrate animals?

speed is related to axon diameter

How is speed of nerve impulse rate related to vertebrates?

speed is combination of axon diameter and layers of myelin (sheath)

What nervous system organization does Phylum Cnidaria (jellyfishes) have?

• simplest neural organization

• nerve net: not a system; simple primitive cells

What nervous system organization does Phylum Platyhelminthes (flatworms) have?

• 2 anterior ganglia, each with network branching off

• weak CNS and PNS (no brain or spinal cord)

What nervous system organization does Phylum Annelida (segmented worms) have?

• brain, ventral nerve cord, simpler motor/sensory neurons

What nervous system organization does Phylum Mollusca (mollusks) have?

• squids and octopus may be equal to fish (not quite)

• complex

What nervous system organization does Phylum Arthropoda have?

• similar to annelida and most mollusks

• EXCEPT the ‘social insects’: well developed brain, complex social behaviors, learning, division of labor, communication

What makes up the vertebrate (central) nervous system?

brain + spinal cord

The brain and spinal cord are surrounded by what 3 meninges (layers)?

1. dura mater (outer)

2. arachnoid (middle)

3. pia mater (inner)

Between each meninge and within each canal of the spinal cord there contains what?

cerebrospinal fluid

brain spinal cord ratios

• fish 2:1

• amphibians 10:1

• reptiles 25:1

• birds 35:1

• humans 55:1

What are the 3 types of skeletons?

1. exoskeletons

2. endoskeletons

3. hydroskeletons

Exoskeletons

external skeleton that surrounds and protects body surface

What type of skeleton do Arthropods have?

Exoskeletons

• made of chitin

• tough and durable

• segmented for movement

• growth requires molting

• vary in complexity, thickness, and durability

• muscles are attached to exoskeletons

Endoskeletons

• internal structures

• DO NOT protect body surface, only some internal organs

• found in echinoderms and vertebrates

• minerals provide firmness

Echinoderms endoskeletons are composed of what?

• composed of spiky networks of proteins and minerals or mineralized plate-like structures

Vertebrate endoskeletons are composed of what?

• composed entirely of cartilage (cartilaginous fishes) or of cartilage and bone

What is the advantage of endoskeletons?

living growth

What are all the functions of the skeleton?

• support/protection, locomotion

• blood cells and platelets are formed in marrow

• calcium and mineral storage

• provides attachment sites for skeletal

cells that form bone

osteoblasts and osteocytes

What are osteoblasts and osteocytes composed of?

• collagen: triple helical structure provides strength and flexibility

osteoclasts

breakdown bone