Animal physiology (IB)

Animal Physiology

The study of the functions and processes of living animals, focusing on organ, tissue, cell, and system interactions that sustain life.

Homeostasis

The maintenance of a stable internal environment within an organism despite external changes.

Negative Feedback

A response that counteracts changes in a system, such as sweating to cool the body when temperature rises.

Positive Feedback

A response that amplifies a change; for example, during childbirth, oxytocin release intensifies uterine contractions.

Set Point

The ideal value of a physiological parameter, such as a body temperature around 37°C.

Adaptation

The ability of animals to adjust to their environments over time.

Circulatory System

Delivers oxygen, nutrients, and hormones while removing waste products from the body.

Pulmonary Circulation

The pathway where blood flows from the heart to the lungs and back for gas exchange.

Systemic Circulation

The pathway where blood is pumped from the heart to the body, delivering oxygen and nutrients.

Plasma

The liquid component of blood that carries nutrients, hormones, and waste products.

Red Blood Cells

Blood cells that contain hemoglobin, which binds to oxygen for transport throughout the body.

White Blood Cells

Blood cells that are part of the immune system, helping to fight infections.

Platelets

Cell fragments in the blood that play a crucial role in blood clotting.

Respiratory System

The system that facilitates gas exchange, absorbing oxygen and expelling carbon dioxide.

Ventilation

The process of moving air into and out of the lungs.

Diffusion

The movement of oxygen from the alveoli into the blood and carbon dioxide from the blood into the alveoli.

Gills

Respiratory structures in aquatic animals that extract oxygen from water.

Lungs

Respiratory organs in terrestrial animals that extract oxygen from air.

Tracheae

A system of tubes in insects that deliver oxygen directly to tissues.

Digestive System

The system that breaks down food into absorbable nutrients and removes undigested waste.

Mechanical Digestion

The physical breakdown of food, such as through chewing.

Chemical Digestion

The enzymatic breakdown of food into smaller molecules.

Absorption

The process where nutrients are taken up in the small intestine, while water and salts are absorbed in the large intestine.

Excretory System

The system that removes metabolic waste products and helps maintain water and electrolyte balance.

Nephron

The functional unit of the kidney responsible for filtering blood and forming urine.

Ultrafiltration

The process where blood pressure forces water and solutes into the nephron.

Reabsorption

The process in the kidneys where useful substances like glucose and water are reabsorbed back into the blood.

Secretion

The process by which waste products are secreted into the urine.

Musculoskeletal System

The system that provides structure, supports the body, and facilitates movement.

Muscle Types

Includes skeletal (voluntary), smooth (involuntary), and cardiac (involuntary) muscles.

Bone Structure

Bones are made of collagen and calcium salts, providing protection and acting as levers for movement.

Nervous System

The system that coordinates body activities, processes sensory information, and sends signals to muscles and organs.

Central Nervous System (CNS)

The part of the nervous system consisting of the brain and spinal cord, which process information.

Peripheral Nervous System (PNS)

The part of the nervous system including nerves that connect the CNS to the rest of the body.

Neurotransmitters

Chemicals that facilitate communication between neurons.

Action Potentials

Electrical impulses that travel along neurons to enable rapid communication.

Synapse

The junction between two neurons where neurotransmitters are released.

Endocrine System

The system that regulates growth, metabolism, and reproduction through hormone secretion.

Pituitary Gland

Gland that secretes growth hormone and regulates other endocrine glands.

Thyroid Gland

Gland that secretes hormones that regulate metabolism.

Adrenal Glands

Glands that secrete adrenaline and cortisol, involved in stress responses.

Male Reproductive System

System responsible for producing sperm and testosterone, delivering sperm into the female reproductive tract.

Female Reproductive System

System responsible for producing eggs and estrogen, facilitating implantation and development of the fertilized egg.

Fertilization

The fusion of sperm and egg to form a zygote, which undergoes development.

Nervous and Endocrine System Interactions

The nervous system provides rapid responses, while the endocrine system offers slower hormonal responses.

Thermoregulation

The process by which animals maintain their body temperature within a narrow range.

Innate Immunity

Non-specific defenses like skin and phagocytes that provide immediate protection against pathogens.

Adaptive Immunity

Specific immune responses to pathogens, involving T cells and B cells.

Inflammation

A response to infection or injury that results in increased blood flow, immune cell activation, and tissue repair.

Energy Metabolism

Biochemical processes that convert food into energy, including catabolism and anabolism.

Aerobic Respiration

A process that uses oxygen to break down glucose, producing a large amount of ATP.

Anaerobic Respiration

A process that occurs without oxygen, producing less ATP and resulting in byproducts like lactic acid.

Dietary Adaptations for Herbivores

Specialized teeth and a large cecum for fermenting plant material.

Dietary Adaptations for Carnivores

Sharp teeth for tearing meat and a shorter digestive tract.

Dietary Adaptations for Omnivores

Variety of teeth and digestive enzymes to process both plant and animal matter.