Foundations of Biological Sciences Final Exam (Exam 5)

Methods of Respiring

• Fish can respire briefly from atmosphere, but once gills dry the surface area reduces and make it impossible for fish to retain enough oxygen

• Humans can’t respire in oxygen at all

True

True or False? In humans, oxygen consumption increases as speed increases.

True

True or False? In fish (in water), oxygen consumption exponentially increases as speed increases.

Hydrodynamic Resistance

Why water is hard to move through

True

True or False? Torpedo shaped fish are the fastest.

Thermoregulation, River Otter

• Endoterm

• Maintains the same body temperature in increasing environmental temperature

Thermoregulation, Bass

• Ectotherm

• body temperature increases an enviornmental temperature increases

Regulation

Animals body temperature remains the same as external temperature increases (sea otter)

Conformers

Animals body temperature increases as external temperature increase (Large mouth bass)

True

True or False? Metabolic ‘investment’ and ‘running costs’ of regulation or conforming must be supported by energy/food

Homeotherms

have increased metabolic rate when external temperature is EITHER higher or lower than preferred body temperature (expensive process)

Poikilotherms

have slowly increasing metabolic rate as external temperature increase (inexpensive process)

Homeostasis

process of regulating internal environment to support physiological systems

Control Mechanism - Negative Feedback Control

• Body notices change in external temperature, control mechanisms sends message to effectors to do something to either increase or decrease internal temperature accordingly

• wait for signal to go ‘wrong’

Control Mechanisms - Positive Feedback Control

• Controlled variable → Sensors → Control mechanisms → effectors

• wait for signal to go ‘right’

Epithelium

sheet of epithelial cells that covers a body surface or organ or lines a body cavity

Simple Epithelium

single layer of cells on a nonliving basement membrane; lines all blood vessels, intestines, and other tubules

Connective Tissue

• Fibrous connective tissue

• Bone

• Cartilage

• Blood

Nervous Tissue

nerves, spinal cord, brain

Types of Muscle Tissue

• Skeletal

• Cardiac

• Smooth

Levels of Animal Cell Specialization

1) Cells

2) Tissues (epithelial, connective, muscle, nervous)

3) Organs (e.g. stomach)

4) Multi-organ systems (e.g. digestive system)

False, organs like the heart are made of two seperate tissues

True or False? Organs are only ever made of one tissue

True; sponges do

True or False? Few animals eat continuously

Maintaining Homeostasis in Digestion

• must regulate release of nutrients to maintain homeostasis

• sophisticated feedback systems involving hormones

  • e.g. glucose (insulin / glucagon)

Diabetes

consequence of not being able to produce enough insulin

Blood Glucose Rise above normal

• stimulates pancreas to secrete insulin

• increase in circulating insulin

• uptake of glucose by cells

• Glycogen (storage form of glucose) synthesis use of glucose in metabolism

• Blood Glucose concentration drops

Blood Glucose drops below normal

• stimulates pancreas to secrete glucagon

• increase circulating glucagon

• Breakdown of glycogen

• release of glucose to blood

• blood glucose level rises

Excretory Systems

• Multiple roles

• Maintenance of internal environment includes

  • Osmoregulation

  • Solute Concentration

  • Removal of nitrogenous wastes

Osmoregulation

• Excretory system

• water

Solute Concentration

• Dissolved Ions / Salts

Regulating the Composition of Body Fluids

• Three Factors

  • Water Volume

  • Solute load (ions)

  • Osmosis

• The composition of water volume and solute load determine the outcome of osmosis

Water Volume

• the correct amount of water in the body is important

True

True or False? A goldfish absorbs water constantly from its environment; the fish must void water as fast as it enters

False, Saltwater fish drink water constantly, but freshwater fish do not drink water

True or False? All fish drink water

The Principle Solutes are

Na+, K+ and Cl-, HOP43-

True

True or False? Ion concentrations determine direction of ion movement and/or osmotic gradients.

Plasma

• similar in composition to interstitial

• has protein anions

Instrastitial

• has lots of potassium, phosphates, and even more protein anions than plasma

• Needs lots of salts outside of the cell

Kidney

• key excretory organ

• functional unit is the nephron

• main function is to regulate the composition and volume of the blood plasma, by selectively removing solutes and water from the plasma

• Adjust the U/P ratio up and down to regulate fluid balance in the body

Nephron

• create urine from blood plasma

  • discharge urine in collecting ducts

• Human kidneys contain over one million _____

True

True or False? The urine/plasma (u/p) ration reflects kidney function.

U/P Ratio

• the ratio of urine and plasma osmotic pressures

• in many animals U/P cannot be higher than 1.0

When U/P is <1.0

• the kidneys are making dilute urine; the plasma is becoming more concentrated

When U/P is >1.0

• The kidneys are making concentrated urine; the plasma is becoming more dilute

True

True or False? Mammals, birds and insects are the only animals that can make urine with U/P > 1.0

True

True or False? Some desert mammals can achieve osmotic U/P ratios as high as 10 or 20

False; ability to produce concentrated urine is important to prevent dehydration

True or False? For groups that live on land, concentrated urine does not need to be produced.

Nitrogenous Waste Excretion

• Carbohydrates and fat end up as water and CO2 and are easily excreted

• Protein and nucleic acid breakdown also produce nitrogenous waste, which can be toxic

Ammonia (NH3)

• is very toxic

• Aquatic organisms can excrete this quickly so it is not a problem

  • Are Ammonotelic, eliminate nitrogenous waste as ______

• Terrestrial animals cannot eliminate _____ quick enough to prevent toxicity

Animals Convert NH3 (Ammonia)

• to urea or uric acid

  • requires ATP (disadvantage)

    • But allows enough time for renal excretion without toxicity

Iso-osmotic

Some have body fluids that are ______ to their environment - Same osmotic pressure

Hyper Osmotic

If body fluids have higher osmotic pressure than the environment

Hypo-Osmotic

is body fluids have lower osmotic pressure than the enviornment

Osmotic Conformer

Allow internal environment to change; tolerate consequences

Osmotic Regulator

maintain internal environment; accept metabolic rates

True

True or False? Water balance and dehydration are the greatest challenges for terrestrial animals

Humidic Animals

body coverings are highly permeable to water, so they lose water by evaporation (millipedes, centipedes, land snails, most amphibians)

Xeric Animals

body coverings precent high rates of water lose (birds, lizards, mammals, insects, spiders)

Blood Filtration in Nephrons

• Bowman’s capsule containing a cluster of capillaries glomerulus

• Blood pressure forces fluid, containing small molecules and ions from glomerulus into Bowman’s capsule

• Proteins and cells remain in the glomerulus (blood)

• Very large amount of filtrate is produced

• Works like a coffee maker

Proximal Convoluted Tubule (PCT)

• In the Nephron

• active transport removes sodium and chloride

• as salt is removed, osmosis starts to remove water

• This retunes most of the filtrate to the blood / body