Bio 192 Exam 3

Form and function is based on…

trial and error

• natural selection

Genetic variations “tested” by environment conditions

• includes physical laws, rates of diffusion, heat exchange, etc
  • rate of exchange proportional to surface area
  • amount needed to exchange (nutrients, wastes, gasses) proportional to volume
• single cell or simple body plans have simpler methods of exchange

All cells of more complex organisms each require …… to ….

require sufficient rates of exchange and contact with environment

• to maintain internal homeostasis “steady state” in more variable environments

Closed circulatory system

blood remains in vessels

Interstitial Fluid

fluid surrounding cells (outside circulatory system)

Atoms to organism

atoms → molecules → organelles → cells → tissues → organs → organ systems → organism

tissues

cells with similar structure and function

Epithelial Tissue

covers body, lines organs and cavities

Types of Epithelial Tissue

* named for number of cell layers and cell shape

• Simple
• Stratified
• Cuboidal
• Columnar
• Squamous

Simple epithelial tissue

1 layer

Stratified epithelial tissue

multiple layers

Cuboidal epithelial tissue

cube shaped

Columnar epithelial tissue

column shaped

Squamous epithelial tissue

flattened

Connective Tissue

Mix of cells and extracellular matrix

• matrix can be liquid, protein, minerals, or a combination

Types of Connective Tissue

• Loose Connective Tissue
• Fibrous Connective Tissue
• Blood
• Adipose Tissue
• Bone
• Cartilage

Loose Connective Tissue

joins tissues, holds organs in place

Fibrous Connective Tissue

tendons and ligaments

Tendons

connect muscle to bone

Ligaments

connect bone to bone

Blood

*Connective Tissue

• matrix is plasma - water, salts, dissolved protein

Adipose Tissue

*Connective Tissue

• insulation and energy

Bone

*Connective Tissue

• matrix of calcium-phosphate

Cartilage

*Connective Tissue

• strong, support

Muscle Tissue

largely actin and myosin protein

Types of Muscle Tissue

• Skeletal Muscle
• Smooth Muscle
• Cardiac Muscle

Skeletal Muscle Tissue

• striated

• voluntary body movements (and diaphragm)

Smooth Muscle Tissue

lacks striations

• used for involuntary organ movements
  • digestive tract
  • urinary bladder
  • arteries

Cardiac Muscle Tissue

• striated heart muscle
• pumps blood

Nervous Tissue

send, receive, and process signals

Nervous Tissue Types

• Neurons
• Glia

Neurons

*Nervous Tissue

• transmit signals

Glia

*Nervous Tissue

• support cells
• nourish, insulate, and replenish neurons

Organ Systems

• Digestive
• Circulatory
• Respiratory
• Immune and lymphatic
• Excretory
• Endocrine
• Reproductive
• Nervous
• Integumentary
• Skeletal
• Muscular

Digestive System Main Components

• Mouth
• Pharynx
• Esophagus
• Stomach
• Intestines
• Liver
• Pancreas
• Anus

Digestive System Main functions

Food processing

• Ingestion
• Digestion
• Absorption
• Elimination

Circulatory System Main Components

• Heart
• Blood Vessels
• Blood

Circulatory System Main Functions

Internal distribution of materials

Respiratory System Main Components

• Lungs
• Trachea
• Other breathing tubes

Respiratory System Main Functions

Gas exchange

• uptake of oxygen
• disposal of carbon dioxide

Immune System/Lymphatic System Main Components

• Bone Marrow
• Lymph Nodes
• Thymus
• Spleen
• Lymph vessels

Immune System/Lymphatic System Main Functions

Body defense

• fighting infections and virally induced cancers

Excretory System Main Components

• Kidneys
• Ureters
• Urinary Bladder
• Urethra

Excretory System Main Functions

Disposal of metabolic wastes

• regulation of osmotic balance of blood

Endocrine System Main Components

• Pituitary
• Thyroid
• Pancreas
• Adrenal
• Other hormone secreting glands

Endocrine System Main Functions

Coordination of body activities

• such as digestion and metabolism

Reproductive System Main Components

• Ovaries or Testes
• Associated organs

Reproductive System Main Functions

Gamete production

• promotion of fertilization
• support of developing embryo

Nervous System Main Components

• Brain
• Spinal Cord
• Nerves
• Sensory Organs

Nervous System Main Functions

Coordination of body activities

• detection of stimuli
• formulation of responses to stimuli

Integumentary System Main Components

• Skin
• skin’s derivatives
  • hair
  • claws
  • sweat glands

Integumentary System Main Functions

Protection against mechanical injury, infection, dehydration

• thermoregulation

Skeletal System Main Components

• Skeleton
  • bones
  • tendons
  • ligaments
  • cartilage

Skeletal System Main Functions

• Body support
• protection of internal organs
• movement

Muscular System Main Components

Skeletal Muscles

Muscular System Main Functions

Locomotion and other movement

Feedback mechanisms …

help maintain homeostasis

Negative Feedback

Response works against stimulus (reduces the stimulus)

• more typical type of feedback

Stimulus: Increased Temperature

Response: Sweating

This is a type of … feedback

Negative Feedback

Stimulus: low blood sugar

Response: hungry

This is a type of … feedback

negative feedback

Positive Feedback

Response amplifies the stimulus

Stimulus: pressure during childbirth

Response: contractions

This is a type of … feedback

positive feedback

Circadian Rhythm

Physiological changes cycling roughly every 24 hours

• occurs in plants and animals

Thermoregulation

Maintain internal body temperature

Temperature affects…

• diffusion rates
• membrane fluidity
• enzyme activity

Warming or cooling by 10 degrees C can…

increase or decrease (respectively) enzyme activity by a factor of 2

too warm can…

denature enzymes, making them nonfunctional

Endothermic

Heat primarily through metabolism

• heat is generated internally
  • mammals, birds, some non-avian reptiles, some fish, many insects

Ectothermic

Heat primarily gained from environment

• amphibians, lizards, snakes, turtles, many fish, most invertebrates

An … animal would maintain energy supply and be much more active in a cold environment.

An … animal would not do much of anything in a cold environment

Endothermic

Ectothermic

Homeotherm

temperature is relatively constant

Poikilotherm

temperature varies with environment

Heat moves from object with higher temperature to lower temperature by…

• Radiation
• Evaporation
• Convection
• Conduction

Radiation

electromagnetic waves

Evaporation

cooling from liquid to gas

Convection

transfer from air or liquid passing a surface

Conduction

direct transfer between objects

Thermoregulation

• Insulation
• Circulatory System
• Evaporation
• Thermogenesis
• Basal Metabolic Rate (BMR)

Insulation

• skin
• hair
• fat
• feathers

Circulatory system in respect to thermoregulation

• Vasodilation
• Vasoconstriction
• Countercurrent Exchange

Vasodilation

expands blood vessels

• more movement of blood to release heat

Vasoconstriction

shrinks blood vessels

• retain heat in blood; less movement of blood

Countercurrent Exchange

transfer heat between blood flowing in opposite directions

• reduces heat exchange to environment
• maintains core body temperature

Evaporation

sweating, panting in birds and mammals

Thermogenesis

metabolic heat protection

• muscle activity, shivering

Non-shivering Thermogenesis

mitochondria generate more heat, less ATP

• H+ bypass ATP synthase
  • primary in brown fat
  • higher abundance in infants and hibernating animals

Hypothalamus

*thermogenesis

negative feedback control

Basal Metabolic Rate (BMR)

energy usage by a resting adult, with an empty stomach, not experiencing stress, at a comfortable temperature

BMR is affected by

• size
• age
• gender

More extreme responses to stress

• Torpor
• Hibernation
• Estivation

Torpor

short term slowing of metabolism in response to extreme heat, cold, or inadequate food

• generally smaller animals
• hummingbirds night time temp can drop by 25 degrees C

Hibernation

long term Torpor from cold/reduced food

• body temperature can cool to near freezing 0 degrees C (32 degrees F)

Estivation

Torpor in response to hot, dry conditions

• conserving water rather than energy

Energy flows, ultimately to…

heat

Organisms use energy and nutrients to…

• grow
• heal
• reproduce
• respond to the environment

Metabolic Diversity

• Autotrophic
• Heterotrophic
• Obligate Aerobe
• Facultative Anaerobe
• Obligate Anaerobe

Autotrophic

“self nourished”

• inorganic carbon source
• Photoautotroph
  • energy source light
• Chemoautotroph
  • inorganic chemical energy source

Heterotrophic

“other nourished”

• organic carbon source
• Photoheterotroph
  • energy source light
• Chemoheterotroph
  • organic compounds energy source

Obligate Aerobe

require oxygen

Facultative Anaerobe

Uses oxygen if available

• can use other electron receptors