STAAR Review 8 Interactions between animal systems Interactions
STAAR Review 8 • Interactions between animal systems • Interactions between plant systems • Homeostasis • Response to external stimuli
Animal Systems Eleven major organ systems: System Function(s) Skeletal Structural support Muscular Movement Integumentary (skin) Barrier from external environment Circulatory/Cardiovascul Transport molecules throughout body ar Respiratory Exchange carbon dioxide & oxygen Digestive Break down food molecules Excretory/Urinary Remove waste products from blood Immune Destroy pathogens that enter body Nervous Send regulatory messages throughout body Endocrine Produce hormones that regulate vital processes
Regulation Regulated body conditions include: • Body temperature • Heart and respiration rates • Molecule concentrations in blood
Body Temperature • Constant internal temperature required to maintain optimal function of cellular processes • Negative feedback loop: – Receptors in skin and brain monitor temperature – High temperature – brain signals sweat glands to cool body down – Low temperature – brain signals muscles to contract (shiver) to warm body up
Body Temperature Organ systems involved: System Functions Integumentary Skin contains temperature receptors & sweat glands Muscular Muscle contractions (shivering) Nervous Brain interprets input from temperature receptors and signals effectors to adjust body temperature
Heart and Respiration Rates • Heart rate – number of • Example: Exercise times heart contracts – Cells utilize oxygen faster per minute – Blood pressure rises to • Respiration rate – meet increased oxygen number of breaths per demand minute – Heart and respiration rates increase • Body varies these rates based on oxygen needs of body cells
Heart and Respiration Rates Organ systems involved: System Functions Circulatory Heart varies heart rate according to signals from brain Respirator y Lungs vary respiration rate according to signals from brain Nervous Monitors blood pressure and oxygen levels Sends signals to heart and lungs to adjust heart and respiration rates
Molecule Concentrations in Blood • Body monitors molecule concentrations in blood to ensure appropriate delivery to and from cells • Regulated concentrations include: – Water balance – Blood sugar • Utilizes hormones sent through blood
Molecule Concentrations in Blood Organ systems involved: System Functions Endocrine Hormone levels regulate molecule concentrations in blood Nervous Receives input from receptors Signals endocrine glands to alter hormone production Excretory Kidneys remove excess water from blood Integumentary Skin contributes to water balance (sweating) Digestive Liver adjusts glucose level in blood to regulate blood sugar Circulatory Blood requires appropriate concentration of molecules Blood transports hormones
Nutrient Absorption • Nutrient absorption – passage of broken down food molecules through intestinal walls into bloodstream to be delivered to body cells Two processes: • Digestion • Absorption
Nutrient Absorption Organ systems involved: System Functions Digestive Mouth, stomach, and small intestine digest large food molecules Small intestine is site of absorption Muscular Muscle contractions push food through digestive tract Muscle contractions in stomach aid mechanical digestion Circulator y Blood vessels absorb nutrients through intestinal walls Blood transports absorbed nutrients to cells throughout body
Defense Against Injury Organ systems involved: System Functions Integumentary Skin provides physical barrier to foreign objects Skeletal Skeleton protect internal organs Muscular Muscle reflexes allow quick reactions Nervous Sensory receptors detect changes in environment Brain sends signals to muscles
Defense Against Illness Organ systems involved: System Functions Integumentar y Skin, hair and mucus provide physical barriers to pathogens Respiratory Nasal mucus and hairs, coughing and sneezing provide physical barriers to pathogens Digestive Stomach acids kill pathogens in food molecules Circulatory Blood transports defensive molecules, white blood cells, and antibodies to site of pathogen Immune Phagocytes and lymphocytes attack and destroy pathogens Adaptive response leads to immune memory
Plant Systems – Shoot system – aboveground – Root system – belowground Shoot system • Organ systems: – Dermal – barrier – Ground – metabolic functions – Vascular – transport Root system • Tissue systems: Tissues Dermal Ground Vascular
Interactions Among Plant Systems Organ and tissue systems interact to carry out vital functions • Transport • Reproduction • Response
Transport • Movement of needed materials throughout plant • Major function of vascular tissue – Xylem – transports water and minerals – Phloem – transports glucose – Both transport hormones
Interactions Among Plant Systems Interactions during transport • Root system – Absorbs water and minerals • Shoot system – Ground tissue produces glucose through photosynthesis • Both organ systems – Produce hormones – Vascular tissue transports all materials throughout the plant
Reproduction Vegetative propagation – offspring produced from part of a plant organ • Asexual Image by Roberto MM [GFDL] Pollination – offspring produced via pollinated seeds • Sexual
Reproduction by Pollination • Flower – organ that produces seeds • Fruit – develops around fertilized ovule(s) • Seed – fertilized ovule (embryo) and stored food (cotyledon) surrounded by a protective seed coat
Interactions Among Plant Systems Interactions during reproduction • Vegetative propagation – Shoot and root systems: part of an organ produces a new plant • Pollination – Shoot system: flowers are the site of seed pollination and fruit development – Shoot and root systems: produce hormones, transported by the vascular tissue, that regulate flower budding, fruit ripening and seed growth
Response • Tropisms – plant’s hormonal growth response toward or away from an external stimulus • Examples: – Phototropism – stem and leaves grow toward a light source – Positive gravitropism – roots grow toward gravity (downward) – Negative gravitropism – stem and leaves grow away from gravity (upward)
Interactions Among Plant Systems Interactions during response • Root system – Grows toward gravity • Shoot system – Grows toward light and/or away from gravity • Both systems – Produce hormones – Transported hormones
Homeostasis – maintaining a stable, internal environment • Essential for life • Involves body systems working together • Involves monitoring levels of variables and correcting changes – – – Body temperature Blood glucose Water potential O 2 and CO 2 concentrations Blood p. H
Negative Feedback Mechanisms Negative Feedback Mechanism – control system (loop) that monitors and corrects changes to maintain homeostasis • Regulation is in a negative, or reverse, direction – Ex: body temperature rises, body acts to cause body temperature to drop
Body Temperature Regulation
Blood Glucose Regulation of blood glucose (sugar) • Involves negative feedback loop • Rise in glucose stimulates secretion of insulin – Insulin – hormone that lowers blood glucose levels
Blood Glucose Regulation
Comparison of Feedback Mechanisms Negative Feedback: • Maintains homeostasis • Corrects change • Regulation is in reverse direction • Examples: – Body temperature regulation – Blood glucose regulation Positive Feedback: • Leaves homeostasis • Increases change • Regulation is in forward direction • Examples: – Blood clotting – Contractions during childbirth
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