C3.1 Integration Of Body Systems

Question 1

Hierarchy of organization in a multicellular organism

Answer 1

Tissues, organs, body systems, organisms

Question 2

Interactions between and within levels of organization result in…

Answer 2

Emergent properties

Question 3

Hormonal signalling type of signal and route

Answer 3

Chemical, in the blood

Question 4

Nervous signalling type of signal and route

Answer 4

Electrical, in neurons

Question 5

Types of response to hormonal signalling

Answer 5

Growth, development, reproduction, changes to metabolic rate, mood etc.

Question 6

Types of response to nervous signalling

Answer 6

Contraction of muscles, contraction of smooth muscle (e.g. gut), change to the rate of cardiac muscle contraction, secretion by glands

Question 7

Speed of response of hormonal signalling

Answer 7

Slower

Question 8

Speed of response of nervous signalling

Answer 8

Very rapid

Question 9

Duration of response, hormonal vs nervous signalling

Answer 9

H: Long duration, until hormone has been broken down. N: short duration, unless nerve impulses are sent repeatedly

Question 10

What is the brain (as an organ)

Answer 10

Integrating organ that receives information, processes it, stores some of it and sends instructions to coordinate life processes

Question 11

What is the spinal cord, where is it and what does it do

Answer 11

Integrating centre for unconscious processes, grey matter inside the vertebral column (backbone), receives information from neurons and pattern of neurons and synapses determine what decisions are made (REFLEXES)

Question 12

Features of unconscious processes

Answer 12

Can happen while asleep, involuntary, controlled by brain and spinal cord, (e.g. peristalsis in intestine, saliva secretion)

Question 13

Features of conscious processes

Answer 13

Only happen when awake, voluntary, controlled by cerebral hemispheres of the brain, (e.g. putting food into the mouth, chewing)

Question 14

Where are receptor cells and what do they do

Answer 14

In skin and sense organs, detect changes in the external environment –> pass the impulses to sensory neurons (some receptor cells are inside to detect e.g. blood pressure)

Question 15

What are chemoreceptors

Answer 15

In the walls of blood vessels, monitor concentrations of oxygen, co2 and glucose

Question 16

Signals from receptors and nerve endings are conveyed to __ by __

Answer 16

the central nervous system, sensory neurons

Question 17

The brain receives all the signals from___ while the spinal cord receives signals__

Answer 17

The main sense organs located in the head – from other organs in the body including skin and muscles

Question 18

What do the cerebral hemispheres (e.g. motor cortex) of the brain do?

Answer 18

CHs play a role in the conscious control of striated muscles, MC can send nerve impulses to any striated muscle in the body

Question 19

What are striated muscles?

Answer 19

Attached to the bone, maintain posture and is used for locomotion

Question 20

Motor neurons in the process of muscle contraction

Answer 20

Located in grey matter, MN dendrites receive signals from interneurons, one axon leads out of the brain and down the spinal cord –> forms a synapse with 2nd MN whose axon leads to striated muscle

Question 21

A nerve is a__ enclosed in __. Most contain both __ and __ neurons

Answer 21

bundle of nerve fibres, a protective sheath. Sensory, motor.

Question 22

Reflex action

Answer 22

Rapid, involuntary response to a specific stimulus. Simplest type of coordination by the nervous system as signals pass through the LEAST amount of neurons –> prevents harm to the body

Question 23

5 stages of REFLEX

Answer 23

1. Receptor cells (or nerve endings in pain and heat) 2. Sensory neurons deliver signals as nerve impulses via long axons 3. Interneurons in grey matter process and make decisions 4. Motor neurons receive signals via synapses with IN and pass it along axon out of CNS 5. Effectors carry out response to stimulus

Question 24

Role of cerebellum

Answer 24

Important in control of skeletal muscle contraction and balance (fine-tunes timing), allows precise control of movements and helps with maintaining posture, helps with activities requiring motor memory (e.g. riding a bike)

Question 25

Circadian rhythms

Answer 25

Rhythms in behaviour that fit humans’ 24h cycle, controlled by internal system

Question 26

Circadian rhythms depend on __

Answer 26

two groups of cells in the hypothalamus called the suprachiasmatic nuclei (SCN) which set a daily rhythm – melatonin causes sleep-wake cycle

Question 27

What is epinephrine and what does it do?

Answer 27

Adrenaline is secreted by adrenal glands and prepares body for physical activity.

Question 28

Effect of adrenaline on target cells

Answer 28

Striated muscle fibres and liver convert stored glycogen to glucose, bronchioles dilate easing ventilation, gas exchange increased by cells in brainstem controlling intercostal muscles and diaphragm, pacemaker speeds up heart rate, atrioles dilate (more blood to muscles and less to gut etc.)

Question 29

Hypothalamus

Answer 29

A small region in the brain that is important in integration of body systems. Links nervous system to endocrine system via PITUITARY GLAND

Question 30

Pituitary gland parts

Answer 30

Anterior (growth, thyroid stimulating, prolactin hormones) and Posterior (antidiuretic (control of blood vessels) hormone and oxytocin)

Question 31

Signals from the cardiovascular centre in the brain reach the SAN (pacemaker) TWO ways:

Answer 31

1. Signals from the sympatetic nerve for increase of HR 2. Signals from vagus nerve to decrease HR

Question 32

Ventilation rate followed by sensory output from chemoreceptors

Answer 32

Chemoreceptors monitor blood pH, o2 and co2 concentrations and alert respiratory centre to act

Question 33

Peristalsis

Answer 33

is the wave of contraction and relaxation in the wall of the gut that moves food from mouth to anus, controlled by enteric nervous system (ENS)

Question 34

Peristaltic muscle structure

Answer 34

Outer wall is longitudinal muscle, inner wall is circular muscle covered in lining (mucosa)

Question 35

Two parts in the gut movements that are not involuntary

Answer 35

1. swallowing 2. defecation (pooping)