BIOL1202 Final

Understand the evolution of the vertebrates and how they differ from the invertebrates.

From Cambrian period (invertebrates) —> vertebrates (356 MYA)

Have a series of bones that make up backbone

Do all chordates have a backbone?

No, 2 invertebrates (urochordates, Cephalochordates) and vertebrates

What are the 4 traits that all chordates have and what role do they play?

1. Notochord: longitudinal rod between digestive tube and nerve cord for skeletal support

2. Dorsal hollow nerve cord: forms the central nervous system from ectoderm rolled into tube and placed dorsal to notochord

3. Pharyngeal slits: used for filter feeding and gas exchange. grooves on surface of pharynx developing into slits open to outside of body. For suspension feeding (invertebrates), gas-exchange (non-limbed vertebrates), in ear, neck, and head for tetrapods. (ex. jaw in humans)

4. Post-anal tail: aids in movement containing skeletal elements.

Lancelets (cephalocordata)

Suspension feeders that keep chordate body plan in adulthood.

Tunicates/sea squirts (Urochordata)

resemble chordata during larval stage (larva —> adulthood =metamorphosis which is the reabsorption of the tail and notochord). They draw in water and filter food particles and shoot water through excurrent siphon when attacked.

Mynxini (Hagfishes)

• jawless vertebrates with reduced vertebrae and flexible cartilage rod from notochord.

• small brain, eyes, ears, and nasal opening and tooth-like structures in mouth.

• Bottom dwelling (eat dead/decaying things)

• Produce slime against predators

• Better to swim with

Petromyzontida (Lampreys)

Jawless vertebrates that use a sucker to clamp its mouth onto live fish/humans. They live as larvae for years, then mature, reproduce, and die within a few days. They have a notochord and a cartilaginous skeleton

Lateral line in fish

rows of organs sensitive to vibrations helping fish detect movement in the water and catch prey

Name for jawed vertebrates

gnathostomes

Chondrichthyes

Skeletal structure made of cartilage

Sharks, rays, ratfishes

Spiral valve in sharks

short digestive tract that increases surface area and slows passage of food.

Oviparous vs Ovoviviparous vs Viviparous

• Oviparous: eggs hatch outside mother’s body. internal or external fertilization. egg yolk provides nutrition to embryo. ex. birds/reptiles

• Ovoviviparous: eggs are retained in oviduct and born after hatching in uterus. internal fertilization. nutrients in yolk content of egg sacs. ex. sharks, rays, snakes, and aquatic species.

• Viviparous: develop in uterus and nourished by mother through placenta and born alive. internal fertilization. ex: humans and most animals

Swim Bladder

An air sac that is used like an internal balloon to rise or deepen to control buoyancy. Found in bony fish. Only found in bony fish

Actinopterygii (ray-finned fishes)

• Fins supported by long, flexible rays that are modified for maneuvering and defense.

• negatively impacted by dams

• Originated during Silurian period

What fish was thought to be extinct then found in 1938

Coelacenths (Actinistia), coast of South Africa

Tetrapod adaptation

1. four limbs and feet with digits

2. a neck for separate movement of the head

3. fusion of the pelvic girdle to backbone

4. absence of gills (except for aquatic)

5. ears for airborne sounds

Dipnoi

linage of lobe-fins that are called lungfishes with lungs.

Amphibians

1. Urodela (salamanders) with tails

2. Frogs (anura) without tails

3. Caecilians (apoda) without legs

Urodela (salamanders)

amphibian with tail

most live on land throughout their entire life

Retention of juvenile features word (common in salamanders)

Pedomorphosis

Anura (frogs)

Lack tails and have powerful hind legs for locomotion on land

Leathery skinned frogs are called toads

Apoda (caecilians)

legless, nearly blind earthworms

Ectothermic vs endothermic

• Ectothermic: absorb heat externally and regulate temperature through behavioral adaptations (ex. most reptiles)

• Endothermic: maintain body temperature through metabolism (ex. birds)

Lepidosaurs

• Lineage of the diapsid (have a pair of holes on each side of skull allowing muscle to pass and attach to jaw)

• Also includes legless living things such as snakes

• ex. lizards, tuataras

Archosaur

Lineage of the diapsid (have a pair of holes on each side of skull allowing muscle to pass and attach to jaw)

ex. turtles, crocodiles, and dinosaurs

Pterosaurs

Tetrapods with flapping flight that went extinct by 66 MYA

Toxins vs Poison

• Toxins: chemical substance produced in living cells (viruses/proteins/peptides)

• Poison: substance that causes illness or death when absorbed (mercury, pufferish)

Bird adaptation

Wings with keratin feathers, lack of a urinary bladder, single ovary, no teeth

Mammal characters

1. mammary glands for milk production

2. Hair and fat layer under skin for insulation

3. kidneys for conserving water

4. endothermy and high metabolic

5. efficient respiratory and circulatory systems

6. large brain-to-body-size ratio

7. extensive parental care

8. differentiated teeth

Monotremes

• Mammalia

• Egg-laying mammals

• ex. echindae and platypus

Marsupiuals

• ex. opossums, kanagroos, koalas

• completes embryonic development while in pouch called marsuipum

Eutherians

• more complex placenta than marsupials

• placental mammals

Anatomy vs Physiology

• Anatomy: biological form of an organism

• Physiology: the biological functions of an organism

• shows how function and form are related

Importance of Surface area (2D): Volume (3D)

• rate of exchange is proportional to surface area

• amount of exchange material is proportional of volume

4 types of animal tissues

1. epithelial: outside of body

2. connective: scattered throughout extracellular matrix

   • collagenous fibers: strength/flexibility

   • reticular fibers: join connective and adjacent tissues

   • elastic fibers: stretch and snap back to original

3. muscle: responsible for body movements containing actin and myosin

4. nervous: receipt, processing, and transmission of information

   • neurons: transmit nerve impulses

   • glial cells: support cells

Connective Tissue

Loose tissue: underlines tissues and holds organs in place

Fibrous tissue: In tendons and ligaments

Bone: mineralized and forms skeleton

Adipose tissue: stores fat for insulation and fuel

Blood: composed of blood cells and cell fragments in blood plasma

Cartilage is a strong and flexible support material

Endocrine System + Nervous System

Endocrine: signals hormones into bloodstream

Nervous: transmits info between specific locations

Work together to coordinate and control in a body

Regulator/Conformer

• Regulator: controls internal change when their is external fluctuation

• Conformer: allows internal conditions to vary with external changes

Homeostasis

• the maintenance of a steady state and internal balance regardless of external environments

• Fluctuations are a stimulus and are detected by a sensor to trigger a response to return to set point

• Ex: body temperature, blood PH, and glucose concentration

Feedback mechanisms

1. Negative: returns variable to normal range (ex. ripening)

2. positive feedback: amplifies stimulus and doesn’t contribute to homeostasis

Circadian rhythm

governs physiological changes and occurs every 24 hours

Acclimatization

a temporary change during animal’s lifetime. this is what adjusts changes for homeostasis. ex. variation of insulation for seasonal changes in birds and antifreeze compounds to prevent ice for other animals in subzero conditions

Thermoregulatory processes

1. thermoregulation: maintain temp in normal range

2. endothermic: generate heat by metabolism (ex. birds, walrus, human)

   • more energetically expensive

3. Ectothermic: gain heat from external sources (fish, amphibians, reptiles)

   • tolerate greater variation in internal temperature

How do organisms exchange heat

1. Radiation

2. Evaporation

3. Convection

4. Conduction

5 adaptations for thermoregulation

1. insulation: countercurrent exchange transfers heat between fluids in opposite direction to reduce heat loss

2. circulatory adaptations: alter flow near body surface in vasodilation (blood flow increases) and vasoconstriction

3. cooling by evaporative heat loss: evaporation of water from skin (ex. sweating or panting)

4. behavioral responses: seek warm/cool places

5. adjusting metabolic heat production: increased metabolism or shivering to generate heat.

   • some can use brown fat that is a tissue specialized for rapid heat production

What part of the brain plays a role in thermoregulation

The hypothalamus, triggers heat loss/generating mechanisms

metabolism relationship to thermoregulation

• Metabolic rate: the sum of energy used in a unit of time

• Basal metabolic rate (BMR): metabolic rate of endotherm at rest at comfortable temperature

• Standard metabolic rate (SMR): metabolic rate of ectotherm at rest at comfy temperature —→ usually lower than endotherms

Relationship between size and metabolic rate

metabolic rate is proportional body mass to the power of 3/4.

Smaller animals have higher metabolic rates per gram

higher metabolic rate = higher oxygen delivery, breathing rate, heart rate, and relative blood volume

Torpor vs Hibernation vs Estivation

• Torpor: decreased activity and metabolism to save energy and avoid certain conditions

• Hibernation: a long-term torpor for winter and food scarcity

• Estivation: summer torpor to survive high temperatures and scarce water

Carnivore vs Omnivore vs Herbivore

• Carnivore: eat other animals

• Omnivore: regularly consume animals and plants/algae

• Herbivore: eat plants and algae

Essential amino acids

• 9 amino acids obtained from food

• meat, eggs, and cheese (complete proteins)

• plants (incomplete…lacking in 1+ of the amino acids)

Essential Fatty Acids

Obtained from diet including unsaturated fatty acids

Vitamins

• organic molecules required in the diet in small amounts

• 13 vitamins are essential

  • Fat-soluble: A, D, E, K… stored in body for long time and are a greater risk

  • Water-soluble: C, B

Minerals

• Inorganic nutrients in small amounts

• Need 200 mg/day (major ones…moderate amounts of Fe and F, and trace amounts of Co, Cu and others)

• large amounts can upset homeostasis and could cause cancer

essential vs nonessential amino acid

Essential amino acids cannot be synthesized by the body and must be obtained from the diet, while nonessential amino acids can be produced by the body.

Food desert meaning

urban area that is difficult to buy/afford good-quality fresh food

Undernourishment

• Diet without enough chemical energy

• Causes break down of own proteins, use up stored fat and carbohydrates, lose muscle mass, suffer protein deficiency, or even death

Substrate Feeders vs Fluid Feeders vs Bulk Feeders

• Substrate: live on food source

• Fluid: suck nutrient-rich fluid from living host (ex. leech)

• Bulk: eat large pieces of food

Digestion vs Absorption vs Elimination

• Digestion: breaking food into molecules small enough to absorb, chewing etc.

• Absorption: uptake of small molecules by body cells

• Elimination: passage of undigested material out of digestive system

Intracellular vs Extracellular digestion

• Intra: particles engulfed by phagocytosis and pinocytosis

  • Sponges

• Extra: breakdown of food outside of cells

gastrovascular canal vs alimentary

• Gastro: in animals with simple body plans. Both digestion and distribution

• Alimentary canal complete tube with both anus and tail in more complex animals

Accessory glands

• glands that secrete digestive glands through ducts into the alimentary canal.

• ex. mammalian, salivary (amylase), pancreas, and liver

Swallowing

• Epiglottis blocks entry to trachea

• bolus guided to larynx then to esophagus

• peristalsis moves it into the stomach

Peristalsis

Rhythmic contractions of muscles in the esophagus canal to move food to stomach

Sphicters

• Regulate movement of material between compartments

• Regulates entry into small intestine and prevents from entering esophagus

• Failure to function can cause acid reflux or heartburn

• Located in between the esophagus and stomach, and between the stomach and small intestine.

processing of particle from beginning to end and what enzymes

no answer :(

Small vs Large intestine roles

Small: Hydrolysis of macromolecules

Large: complete recovery of water and makes wastes solid to move through colon and store in the rectum until they are eliminated through the anus

How surface area is related to digestion

no answer :(

Dentition

• an animals assortment of teeth, reflecting their diet

• Carnivores have canines, herbivores do not

• How many teeth do human have: 32

Mutualistic Adaptations

Some intestinal bacteria produces vitamins and also regulate the development of the intestinal epithelium and the function of the immune system you’re born with

Microbiome

A collection of microorganisms living on the body

(picture with pie charts)

Mutualistic adaptations in herbivores

Location: Fermentation chambers

Organism: microorganisms that digest cellulose

BMI

Underweight: 18.5 or lower

Normal weight: 18.5 to 24.9

Overweight: 25 to 29.9

Obese: 30 to 39.9

Morbidly obese 40 or higher

Glucose homeostasis

• Involves insulin and glucagon to regulate breakdown of glycogen into glucose

• Maintains stable blood sugar levels in the body.

• Its feedback system is a negative feedback loop

• Diabetes: deficiency of insulin and unable to take up enough glucose for metabolism

  • Type 1: Destroying of beta cells in pancreas

  • Type 2: Failure to respond normally to insulin

Regulation of satiety

Hormones that regulate long and short term appetites

• Ghrelin: triggers hunger before meals

• Insulin and PYY to suppress appetite

• Leptin: regulates body fat levels

Open vs Closed Circulatory System

• Open: uses circulatory fluid called hemolymph to bathe organs

• Closed: blood is confined to vessels

  • Ex. Humans (cardiovascular system)

Single vs Double Circulation

• Single: blood passes through 2 capillary beds before returning,

  • ex. fish

• Double: Higher blood pressure —> deoxygenated and oxygenated are separated

  • ex. amphibians, reptiles, and mammals

Intermittent breather meaning

Long periods without gas exchange or relying on gas exchange. Happens in amphibians

What are the two values of blood pressure

Systolic and diastolic pressure