final exam animal physiology comprehensive set

Gas solubility

↑ with pressure; ↓ with temperature.

Mammals vs Birds ventilation

Mammals = tidal ventilation; birds = unidirectional.

Respiratory surfaces

Use passive diffusion.

Birds oxygen maximization

Maximize O₂ via cross-current flow.

Opercular pumping

A method of fish respiration.

Ram ventilation

Swim with mouth open.

Partial pressure

Subtract water vapor pressure first.

Adaptation

Heritable trait increasing survival & reproduction.

First defense vs environment

Behavior.

Stenothermal

Narrow temperature range.

Eurythermal

Wide temperature range.

Ectotherm metabolic rate

↑ with temperature & digestion.

TNZ

Range where basal metabolism maintains body temperature.

Small endotherms

High heat loss, narrow TNZ.

Endotherms

High metabolic rate, internally regulated, homeothermic.

Ectotherms

Low metabolic rate, environment-driven, poikilothermic.

Torpor

Short-term metabolic drop.

Estivation

Warm/dry dormancy.

Brown fat

Nonshivering thermogenesis.

Piloerection

Insulation.

Adaptive hyperthermia

Allow body temperature to rise to reduce water loss.

Behavioral cold tolerance

Burrowing, basking, posture changes.

Blood pressure in feet

Higher due to gravity.

Aids to return blood

Valves, vasoconstriction, tight skin (NOT countercurrent).

Myogenic heart

Beats without neural stimulus.

Fish heart structure

2 chambers.

Amphibian heart structure

3 chambers.

Reptile heart structure

3 with partial septum.

Crocodilian heart structure

4 chambers.

Bird/Mammal heart structure

4 chambers.

O₂ in ETC

Final electron acceptor.

Foregut fermenters

Digest low-quality food effectively.

Endocrine system

Slow, long-lasting, bloodstream, broadcast.

Nervous system

Fast, point-to-point, electrical.

Fight/flight response

Sympathetic.

Sensory pathway

Sensory → CNS → motor output.

Dorsal spinal cord damage

Results in loss of sensation.

Hormone interactions

Synergism (amplify), permissiveness (requires another), antagonism (oppose).

Steroid hormones

Lipid-soluble (testosterone, estrogen).

Peptide hormones

Many amino acids (insulin).

Amine hormones

Simple (adrenaline).

Functional hormones

Metabolism, stress, contraction, reproduction.

Major endocrine organs

Hypothalamus-pituitary: master regulation.

Pineal gland

Produces melatonin (circadian).

Thyroid gland

Regulates metabolism.

Thymus gland

Involved in immune maturation.

Pancreas

Produces insulin/glucagon.

Gonads

Produce sex hormones & gametes.

Reproductive goal

Survive + reproduce.

Natal philopatry benefits

Proven habitat success.

Precocial vs Altricial

Precocial = developed at birth; altricial = helpless.

Reproductive strategies

Semelparity: one big event, many offspring, death.

Iteroparity

Repeated reproduction.

Parthenogenesis

Females only.

Sequential hermaphroditism

Change sex.

Brood parasitism

Lay eggs in another's nest.

Ovoviviparity

Internal eggs, yolk nutrition.

Parental care

External fertilization → high paternity certainty → more male care.

HPG Axis

Controls reproduction via GnRH → LH/FSH → sex steroids.

Menstrual cycle

Follicular = rising estrogen + follicle growth.

Migration activation

Often activates reproduction via environmental cues.

Navigation types

Route/trail following = cues left behind.

Piloting

Using landmarks.

Path integration

Internal tracking.

Compass navigation

Using sun/stars/magnetic.

Map-and-compass navigation

Position + direction.

Early arrival mismatch

Can lead to chick starvation.

Climate risk for reptiles

With TSD: skewed sex ratios, population collapse.

What is reproduction?

A complex physiological process regulated by hormones, essential for species continuation, and varies across different animal taxa.

What is the Hypothalamic-Pituitary-Gonadal (HPG) Axis?

A key regulatory system in both male and female reproductive physiology involving hormones such as GnRH, FSH, LH, Testosterone, Estrogen, and Progesterone.

What is spermatogenesis?

The process of sperm production in males, involving Sertoli and Leydig cells.

What are the primary phases of the female reproductive cycle?

Follicular and luteal phases, including oogenesis and the ovulation process.

What is the difference between estrous and menstrual cycles?

Estrous cycles occur in some mammals, while menstrual cycles are characteristic of others, with specific hormonal fluctuations.

What is parthenogenesis?

A form of asexual reproduction where females produce offspring without male fertilization, exemplified by whiptail lizards.

What is sequential hermaphroditism?

A reproductive strategy where an animal changes sex during its lifetime, such as clownfish starting as males and becoming females.

What is brood parasitism?

A reproductive strategy where one species relies on another to raise its young, as seen in the common cuckoo.

What is semelparous reproduction?

A reproductive strategy where reproduction occurs once in an organism's lifetime, often producing many offspring at once.

What is iteroparous reproduction?

A reproductive strategy where reproduction occurs multiple times throughout an organism's lifetime, allowing for higher investment in offspring care.

What is embryonic diapause?

A reproductive strategy where embryonic development is arrested or slowed, observed in various species including some mammals.

What are precocial and altricial young?

Precocial young are relatively mature and mobile at birth, while altricial young are born helpless and require extensive parental care.

What is the 'Mafia Hypothesis' in parental care?

A theory suggesting that parents may adopt young that are not their own due to the risk of losing their own offspring if they do not.

What are the three hypotheses explaining why parental care is often provided by females?

1. Low reliability of paternity, 2. Order of gamete release, 3. Association with young.

How does photoperiod affect animal reproduction?

Day length can regulate breeding timing by triggering hormonal changes, influencing reproductive cycles in many species.

What is temperature-dependent sex determination (TSD)?

A mechanism in some reptiles where the temperature during egg incubation determines the sex of the offspring.

How do pheromones influence reproduction?

Pheromones are chemical signals that can synchronize estrous cycles or attract mates, affecting reproductive behaviors.

What impact does resource availability have on reproduction?

Access to food and nesting materials can directly affect reproductive success, influencing the number of offspring produced.

How does social structure influence breeding in animal species?

Social hierarchies often dictate who gets to breed, as seen in species like wolves and naked mole rats.

What are some modern challenges to animal and human reproduction?

Climate change, habitat fragmentation, endocrine disrupting chemicals, conservation breeding programs, and assisted reproductive technologies.

Sensory neurons:

bring info to CNS.

Motor neurons:

carry commands from CNS.

endogenous rhythms

Internal cycles (not limited to 24 hours).

Nervous System

Uses electrical impulses and neurotransmitters.

Nervous System Responses

Fast, specific, short-lived responses.

Point-to-Point Signaling

Signaling from neurons to synapses to target.

Endocrine System

Uses chemical messengers (hormones) released into bloodstream.

Endocrine System Effects

Slower, longer-lasting effects.

Wide Broadcast

Hormones can affect multiple organs/tissues.

Hormone Targets

Hormones can have multiple targets and cyclic secretion patterns.

Hormonal Interactions

Hormones may interact synergistically, antagonistically, or permissively.

Central Nervous System (CNS)

Brain + spinal cord → integrates & processes info.