nervous system

Question 1

what is the nervous system organization in cnidarians?

Answer 1

these animals are the simplest organisms with nervous systems. they possess a nerve net composed of interconnected neurons. unlike more complex organisms, they lack a central control organ. Instead, impulses can travel in both directions, spreading throughout the nerve net.

Question 2

what is the nervous system organization in echinoderms?

Answer 2

they have a central control structure called a nerve ring that signals radial nerves and signal muscles

Question 3

what is the nervous system organization in bilateria?

Answer 3

There is considerable variation within the phylum Platyhelminthes. For example, in planarians, we find the simplest clearly defined central nervous system (CNS). They possess a brain and eyespots located at the anterior end. Their nervous system has a ladder-like structure, consisting of two longitudinal nerve cords with transverse nerve “rungs.”

Question 4

what is the nervous system organization for annelids and arthropods?

Answer 4

they have more complex brian, they have a ganglia which is segmentally arranged clusters of neurons,

Question 5

what is the nervous system organization for vertebrates?

Answer 5

the brain and spinal cord make up the CNS and the nerves and ganglia make up the PNS

Question 6

how does nervous system effect lifestyle?

Answer 6

chitin are slow moving and have a simple nervous system while squid are fast moving and have a more complex nervous system

Question 7

what are adult glial cells?

Answer 7

these cells have several important functions. In the central nervous system (CNS), oligodendrocytes are responsible for myelination, which involves wrapping axons with a fatty substance called myelin. In the peripheral nervous system (PNS), Schwann cells perform a similar function, providing myelination to axons.

Question 8

what are radial glia cells?

Answer 8

they form new tracks in the developing embryo, newly formed neurons migrate from neural tube along tracks

Question 9

what makes up the CNS?

Answer 9

the brain, which is the central control organ, and the spinal cord which is the link between the brain and rest of NS.

Question 10

what are the functions of the spinal cord?

Answer 10

transmits impulses to/from brain, controls reflex actions which are rapid involuntary responses to a stimulus (knee jerk reflex)

Question 11

what makes up the spinal cord?

Answer 11

the spinal cord is dorsal within the spine (goes along neck/back), it has a small central canal with fluid, gray matter surrounds the canal and white matter surrounds the gray

Question 12

what is the peripheral nervous system (PNS)?

Answer 12

Nervous tissue that is not part of the central nervous system (CNS) plays a crucial role in transmitting signals to and from the CNS. This includes sensory receptors, which detect stimuli from the environment, and nerves, which carry these signals to the CNS for processing and interpretation.

Question 13

what are sensory receptors?

Answer 13

part of the PNS, they are used for the detection of stimuli: visual, auditory, and chemical

Question 14

what are nerves?

Answer 14

Cranial nerves originate from the hind part of the brain and innervate the head and face. In contrast, spinal nerves originate from the spinal cord and innervate the entire body.

Question 15

what are the two functional components of the PNS?

Answer 15

afferent neurons and efferent neurons

Question 16

what are afferent neuron?

Answer 16

also known as sensory neurons, detect stimuli from the external environment or internal body conditions and send signals to the CNS for processing

Question 17

what are efferent neurons?

Answer 17

also known as motor neurons, type of nerve cell that carries signals from the central nervous system (CNS) to muscles or glands. They are responsible for transmitting commands from the brain or spinal cord. there are two components, the motor system which has control over skeletal muscle (voluntary and reflexes) and the automatic nervous system which are our glands, heart, and smooth muscle (not consciously controlled movement)

Question 18

what is the pathway of a signal?

Answer 18

stimulus -> sensory receptor -> afferent neuron -> CNS -> efferent neuron -> motor/automonic system -> effector

Question 19

what is the parasympathetic division?

Answer 19

rest and digest

Question 20

what is the sympathetic division?

Answer 20

fight or flight

Question 21

how does the brain develop?

Answer 21

starts as a neural tube, a single tube of tissue, as development progresses, the anterior (front) part of the neural tube folds and expands to form the various regions of the brain. The posterior (back) part of the neural tube remains relatively straight and becomes the spinal cord.

Question 22

what is the cerebrum?

Answer 22

the most prominent part of the brain, it is responsible for voluntary movement, learning, emotion, memory, and perception

Question 23

how is the brain divided?

Answer 23

the brain consists of two hemispheres, the right and left, each responsible for various functions including perception and motor control. these hemispheres are connected by a bundle of nerve fibers called the corpus callosum, which allows for communication between the two halves of the brain.

Question 24

what is the cerebellum?

Answer 24

located at the back of the brain and is primarily responsible for coordinating movement and balance. It plays a crucial role in fine motor skills and coordination, helping to control the position of joints and the length of muscles. Additionally, integrates sensory information from the ears and eyes to help maintain balance and posture. Damage can result in permanent loss of coordination and motor skills.

Question 25

what is the diecenphalon?

Answer 25

a region in the brain that includes the thalamus, which acts as a relay center for sensory information destined for the cerebrum, ensuring it reaches the correct areas for processing. Additionally, the hypothalamus, another structure in this region, regulates the pituitary gland and is involved in controlling hunger, thirst, sexual behavior, and emotional responses such as rage.

Question 26

what is the brainstem?

Answer 26

region that includes the midbrain, pons, medulla, and oblongata

Question 27

what is the function of the midbrain?

Answer 27

found in the brainstem, receives, integrates, and routes sensory info

Question 28

what is the function of the pons?

Answer 28

found in the brainstem, respiratory and sleep centers

Question 29

what is the function of the medulla?

Answer 29

found in the brainstem, continuous with spinal cord, basic life functions such as respiration, heartbeat, BP, swallowing, coughing, vomit