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Explain the negative feedback system for drop in blood pressure
A drop in blood pressure is detected
The medulla oblongata in the brain receives this signal
The medulla oblongata stimulates the nerve pathway
The nerve pathway signals the heart to increase its rate
The nerve pathway also signals arterioles to constrict
Increased heart rate and arteriolar constriction rise blood pressure
The rise in blood pressure is detected inhibiting further stimulation of the heart and arterioles
Blood pressure returns to normal
Explain a positive feedback look for the suckling by the baby during lactation
The suckling of the baby is sensed by the nerve endings
The hypothalamus see this
It releases oxytocin and the milk duct contractions
Milk is ejected
Increased suckling
Only stops when suckling stops ( baby is full)
What is thermoregulation
Maintenance of the body temperature within a range that enables cells to function efficiently
What are ectotherms
An animal that is dependent on external sources of body heat
What is an endotherm
An animal that is dependent on or capable of the internal generation of heat
What is hypothermia
A condition in which the bodies core temperature falls below the normal range
Why is freezing dangerous for cells
It can cause crystals to form, which may puncture cell membranes and lead to cell damage or death.
What is the source, target and action of ADH
Source- pituitary gland
Target-kidneys
Action- water reabsorption
What is the source, target and action of aldosterone
Source- adrenal gland
Target- kidneys
Action- enhances renal function
What is the source, target and action of insulin
Source- beta cells islets of langerhans
Targets- liver
Action- decreases blood sugar levels
What is the source, target and action of glucagon
Source- alpha cells islets of langerhans
Targets- liver
Action- raising blood sugar
What is the source, target and action of epinephrine and adrenaline
Source- adrenal medulla
Target- muscle, lungs, heart, and blood vessels
Action- fight or flight
What is the source, target and action of cortisol
Source- adrenal gland (adrenal cortex)
Target- every cell and organ in the body
Action- converts amino acids to glucose and breaks down fats
What is the source, target and action of ACTH
Source- anterior pituitary gland
Targets- adrenal cortex
Action- stimulates cortisol which regulates metabolism
What is the source, target and action of thyroid hormone
Source- thyroid gland
Target- brain, liver, skin
Action- regulates metabolism and growth
What is the source target and action of TSH
Source- anterior pituitary gland
Targets- thyroid gland
Action- tells your thyroid how much thyroid hormone to make
What is the source, target and action of TRH
Source- cell bodies of the hypothalamus
Target- Anterior pituitary gland
Action- stimulate cells in the anterior pituitary gland to release TSH
What is the source target and action of calcitonin?
source-Thyroid gland
Target- Bones
Action-lowers blood calcium levels
What is the source target and action of PTH?
Source-Parathyroid gland
Target-Bones
Action-Increases blood calcium levels
What is the source target an action of growth hormone?
Source-Anterior pituitary gland
Target-Liver and muscles and bones
Action-Stimulates bones and tissue growth
What is the source target in action of prostaglandins?
Source-All tissues and organs
Targets-You tissues
Action-Mediates inflammation and pain
What is the source target in action of Anabolic steroids
Source-Synthetic versions
Targets-Muscle cells
Action-Promotes muscle growth and maculation
What is the source target in action of EPO?
Source-Kidneys
Targets-Bone marrow
Action-Boost red blood cell production
What is the source target in action of testosterone?
Source- interstitial Cells
Target-Reproductive tissues
Action-development of male reproductive organs
What is the source target in action of FSH?
Source-Anterior pituitary gland
Targets-follicle
Action-Maturation of sex cells in female
What is the source target in action of LH?
Source-Anterior pituitary gland
Target-Corpus Luteum
Action-Triggers, ovulation, and progesterone
What is the source target in action of estrogen?
source-Ovaries
Target-Reproductive organs
Action-Female reproductive development and regulates menstrual cycle
What is the source target in action of progesterone?
Source-Corpus luteum
Target-Uterus
Action-Prepares uterus for pregnancy
What is the source target in action of prolactin?
source-Anterior pituitary gland
Targets-Mammary glands
Action-Milk reproduction
What is the source target in action of oxytocin?
Source-Posterior pituitary gland
Target-Uterus and mammary gland
Action-Stimulates uterine contractions during childbirth and milk production
What is a source target action of MSH?
Source-Anterior pituitary gland
Targets-Skin
Action-Stimulates melanin production
What is homeostasis?
The ability of a cell or organism to maintain a stable internal environment when outside conditions change
What is negative feedback
A change in some variable triggers mechanics that reverse the change
What is positive feedback?
A change in some variable triggers mechanisms that amplify the change
What are the two major systems of homeostasis?
The endocrine system and the nervous system
What is the endocrine system?
The endocrine system is slow communication messages travel by means of chemical hormones from a source to a target. It involves their source target in action.
What is the nervous system?
The nervous system is fast communication with high-speed nerve impulses that are conveyed along. Nerve cells called neurons.
What is a gland? What are the type types of glands?
It is a secretary organ
Exocrine glands and endocrine glands
What are exocrine glands?
They have ducks through which secretion travels an example is sweat, mucus, tears, digestive enzymes
What is an endocrine gland?
It is ductless glands, and it produces hormones and secretes them into the bloodstream
What are the three things that define an animal hormone?
It is a specific molecule synthesized and secreted by an endocrine gland
It is released into the circulatory system
It travels via the blood to another area of the body, where it elect specific biological responses from target cells which have receptors for the hormone
What are receptors?
Proteins within the target cell or on its surface
Specific for certain hormones
Hormones bind to receptors molecules and it is the hormone/receptor complex that triggers the effect
What are the three general classes based on their chemical structure of hormones?
Steroid hormones, amino acid derivatives and polypeptides
What are steroid hormones?
Includes the sex hormones
Fat soluble
Cholesterol is the precursor
examples include estrogen, progesterone, and testosterone
What are amino acid derivatives?
Hormones derived from amino acids, Especially tyrosine
Water soluble
Smaller than a steroid molecule
Example is Epinephrin and adrenaline
What are polypeptides?
The most diverse
Chains of amino acid
Example as insulin
What are the three principles governing hormone activity?
Hormones can act at very low concentrations
A given hormone can affect different target cells in an animal differently or very in effects from one species to another
A hormone trigger specific changes in a target cell by one of two general Mechanisms
A hormone can Enter the nucleus of the target cell and influence the expression of cells genes
A hormone can attach to the cell surface and influence activity within the cell through cytoplasmic intended call second messenger
How do steroid hormones enter the cell?
Steroid hormone from the bloodstream arrives at the target and passes easily through the cell membrane because it is lipid soluble
The steroid hormone is then able to enter the nucleus through the nuclear membrane
Once in the nucleus, the hormone will then combined with a receptor molecule from hormone receptor complex
The hormone receptor complex well, then, combined with an acceptor molecule, located in the chromatin and form a receptor acceptor complex
The acceptor is associated with the DNA/gene which will activate or turn on the gene
The gene is then copied from DNA into a working copy called mRNA
The working copy of mRNA goes from the nucleus into the cytoplasm where it is translated or converted into a sequence of amino acids producing the first second third levels of protein structure
What are the anterior lobes two steps to hormones?
Releasing factors are secreted
Target sells synthesize appropriate hormone in response to releasing factor
What happens during short term stress response?
Increase heart rate
Increase blood pressure
Liver converts glycogen to glucose and releases glucose to the blood
Dilation of bronchioles
Decreased digestive system activity
Decreased urine output
Changes in blood flow patterns
Increase alertness
What is the long-term effects of stress caused by aldosterone?
Retention of sodium and water by kidneys
Increase blood volume in blood pressure
What are the long-term affects of cortisol on stress response?
Increase blood sugar
Proteins and fats broken down for energy
What are the functions of the testes?
Produce sperm cells
Produce the hormone testosterone
What is the function of seminiferous tubes?
Produce immature, sperm cells
What is the function of seminal vesicles?
Secretes fructose into the semen, which provide provides energy for the sperm
What is the function of the prostate gland?
Secretes and alkaline buffer into the cement to protect the sperm from the acidic environment of the vagina
What is the function of cowpers gland?
Secrete mucus, rich fluids into the semen that may protect the sperm from acids in the urethra
What is the function of the urethra?
Carries semen during ejaculation
Carries urine from the bladder to the exterior of the body
What is the function of the penis?
Deposit sperm into the vagina during ejaculation
Contains the urethra
What is the function of ovaries?
Produce the hormones, Oestrogen and progesterone
Sites of over development and ovulation
What is the function of the fallopian tubes?
Carries the ovum from the ovary to the uterus
Usually the site of fertilization
what is the function of the fimbria
Sweeps the ovum into the oviduct following ovulation
What is the function of the uterus?
Pear shaped organ in which the embryo and foetus develop
Involved in menstruation
What is the function of the cervix?
Separates the vagina from the uterus
Holds the foetus in place during pregnancy
Dilate during birth to allow the foetus to leave the uterus
What is the function of the vagina?
Extends from the cervix to the external environment
Provides a passageway for sperm and menstrual flow
Functions as the birth canal
What happens when there’s no embryo
The corpus luteum stops making progesterone and estrogen, and the endometrium stops developing and breaks down
What are the four Stages in the menstrual cycle
Flow
Follicular
Ovulation
Luteal
What happens during the flow phase? And how long does it last?
Menstruation the endometrium is shed through the vagina and last one to five days
What happens during the follicular phase?
Follicles containing eggs develop in ovaries and the endometrium begins to develop FSH from the anterior pituitary gland helps follicles develop this increases oestrogen this process last 6 to 13 days
What happens during ovulation?
One egg cell burst from the follicle in ovary and enters oviduct Towards the uterus, LH is produced from the pituitary gland. This happens on day 14.
What happens during the luteal phase
Follicle turns into yellow body from LH oestrogen is produced and so is progesterone if pregnancy doesn’t occur the endometrium is maintained this happens on day 15 to 28
What are the steps in menstruation?
Anterior pituitary releases FSH
FSH stimulates follicles to grow
As follicle grows cell of follicle releases, estrogen, larger amounts of secreted oestrogen increases
Oestrogen stimulates the endometrium to begin to develop
High levels of oestrogen feedback to pituitary to turn off FSH
Anterior pituitary, then secretes LH
LH promotes ovulation of the fully developed follicle
Corpus selenium continues to secrete oestrogen as well as progesterone
Progesterone maintains endometrium
SH when no fertilization takes place egg dies, and LH secretion stops
Without any LH corpus lithium cannot be maintained the progesterone secretion will stop
With progesterone stops menstruation begins
What takes place during the transport of epithelium
Filtration between the glamorous and Bowmans capsule
Reabsorption good materials are made from the Filtrate/nephron back into the bloodstream
Secretion the bad waste or access materials are removed from the blood into the filtrate
What are the two parts of the nervous system?
Central nervous system and peripheral nervous system
What does the Central nervous system involve
The brain and the spinal cord
What does the peripheral nervous system involve?
Somatic nerves, and autonomic nerves
What are The somatic nerves
Voluntary sensor and motor responses
What is the autonomic nerves?
Involuntary sympathetic, which is your fight or flight response and your parasympathetic, which is your calm, relaxed response
What are neurons?
The functional unit of the nervous system
What are the three groups of neurons?
The sensory neurons which are photo receptors in the eyes, fear the afferent neurons
Inter neurons, they link neurons within the body. They are called association neurons.
Motor neurons, they are linked to muscles also called efferent neurons
What are the events of the reflex arc
Stimulus causes action potential in the sensory receptor
Message travels along sensory dentries
Message travels along sensory axon
Message reaches and turn on dendrite
Message splits one to brain one to motor neuron dendrite
Message travels along motor neuron axon
Message causes muscles to contract
What is an action potential?
Is an all or none event
Is unidirectional
Has the same amplitude each time?
What is the process of action potential?
The action potential arrives at the terminal button
The membrane will start to become leaky to calcium ions
Calcium ions, move towards the neurotransmitters in vesicles to help the neurotransmitters fuse with the cell membrane of the terminal button of the pre-synoptic cell
The vesicle fuses with the cell membrane, allowing the neurotransmitter to exit into the synaptic gap via exocytosis
The neurotransmitter will then diffuse across the synaptic gap
The neurotransmitter will bind with a specific cell membrane receptor, and the postsynaptic cell
If the neurotransmitter is excitatory it will lead to a graded potential in the postsynaptic cell if the neurotransmitter is inhibitory, it will lead to the hyperpolarization of the post synaptic cell
What is nerve impulse theory?
The wave of depolarization sweeps the length of the axon ending at the terminal button. There is a short refractory period of several milliseconds during which the normal ion distribution is reestablished an impulse cannot be initiated during this. Period.
What is the pituitary gland?
The master gland, it secretes hormones that influence a wide range of functions from body growth to human reproduction
What is a thalamus?
A relay station for all sensory input
What is the hypothalamus?
Governs the autonomic nervous system, and the pituitary gland
Body temperature
Appetite
Thirst
What is the frontal lobe?
The front of the brain responsible for personality, decision-making planning, and problem-solving
What is the occipital lobe?
The back of the brain responsible for vision
What is the corpus Callosum
Connect left and right hemisphere
Allows left, and right hemisphere to communicate
What is the pons
Relay station to and from the cerebellum
What is the medulla oblongata?
Responsible for breathing, heart rate and blood pressure
What is the cerebellum?
Responsible for balancing coordination
What is the temporal lobe
Hearing auditory cortex memory
What is the Parietal lobe
Pressure temperature
3-D battle spatial Perception
Limb awareness
Silent areas
What is the hippocampus?
Gives rise to emotions and allows us to feel other emotions and stories memories
What is the reticular formation?
The primary regulator and consciousness
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