Biological systems Flashcards
List the layers found in a blood sample when put into a centrifuge.
Plasma, buffy coat layer (thrombocytes and leucocytes), erythrocytes
What is the difference between systemic and pulmonary circulation.
Systemic pumps blood around the body, pulmonary pumps blood to the lungs.
What is the function of the vena cava?
Takes blood from the body to the right atrium.
What is the function of the chordae tendinea?
Anchors the atrio-ventricular valves.
What do atrio-ventricular valves do?
Separate the atrium and ventricles to prevent backflow.
What do coronary vessels do?
Provide the heart with its own blood supply.
What is the function of semilunar valves?
They prevent backflow in the ventricles.
What is epithelial tissue?
Tightly packed cells with one side exposed to air and the other side a basement membrane. It covers the outside of the body and lines internal organs.
What is the purpose of epithelial tissue?
Barrier against mechanical injury, invasive microorganisms and fluid loss. Also provides a surface for absorption, excretion and transport of molecules.
What are the three types of epithelial tissue and what are the different thickness types known as?
Squamous, cuboidal and columnar. 1 layer=simple. more than 1 layer=stratified, pseudostratified=1 layer disguised as 2
What is the layer sometimes found on top of epithelial tissue known as and what does it do?
Cilia, used to catch pathogens and helps with movement.
What is the difference between mechanical and cellular respiration?
Mechanical is the process of breathing, taking in oxygen and releasing carbon dioxide. Cellular is the process by which the body receives energy.
What 7 structures make up the respiratory system?
Nose, pharynx, larynx, trachea, bronchi and bronchioles, alveoli.
What are turbinate bones and what is their function?
fine scrolls of bone, highly vascular and lined with ciliated mucous epithelial tissue. Responsible for filtering out dust and other foreign matter as well as moistening the air.
What are sinuses and what do they do?
Air filled cavity. Lightens the skull and allows the area of the skull used for muscle attachment to be larger. Also used for heat exchange and sites for mucous secretion.
What are the three divisions of the pharynx?
nasopharynx, oropharynx, laryngopharynx.
List the order of the 4 structures of the urinary system.
Kidneys, ureters, bladder, urethra.
What does ADH stand for?
Anti diuretic hormone.
What do ADHs do?
Control the kidneys. The brain detects any change in water concentration and allows the kidneys to absorb more or less water.
What is the term for a ripe ovarian follicle?
Graafian follicle.
What are the 7 parts of the female reproductive system?
Ovary, uterine tube (fallopian tube), uterus (horn and body), cervix, vagina, vestibule, vulva.
The ovary is attached to the abdominal wall by the…
Mesovarium.
What’s the difference between spontaneous ovulation and induced ovulation?
Spontaneous=independent of mating. Induced=ovulation induced/caused by mating
Part of the mesovarium forms a pocket like structure known as…
The ovarian bursa.
The funnel shaped end of the ovarian tube is called the…
Infundibulum.
What can be found in the uterine tube that propels ova towards the uterine horns?
Cilia.
What is another term for mating?
Copulation.
What are the 3 layers of the uterus?
Endometrium, myometrium, mesometrium.
What forms at the site of a ruptured follicle and produces progesterone?
Corpus leuteum.
Each ripe follicle contains…
A large amount of fluid and one ovum.
Parturition is another term for what?
Giving birth.
Name the 6 main hormones associated with the female reproductive system.
Oestrogen, FSH, LH, oxytocin, progesterone, prolactin.
For roughly how long does a dog ovulate and how long is their oestrous cycle?
Ovulate 4-13 days, cycle is approx 90 days
How many chromosomes do dogs have?
78
What does FSH stand for?
Follicle stimulating hormone.
Where is progesterone released from and what does progesterone do?
Released from corpus luteum and function is to promote and maintain early pregnancy.
What are the 5 steps of an oestrous cycle?
Pro-oestrous, oestrous, metoestrous, dioestrous, anoestrous.
Give 3 functions of the testes.
Produce sperm, produce fluid for transportation, secrete testosterone.
What is the main difference between a dog and cats Penis?
That cats glans penis is covered in barbs that elicit a pain reflex in the female to induce ovulation.
What are the 3 types of cells found in the testes and what are their functions?
Spermatogenic-transform to sperm, sertoli-nurse cells for sperm, cells of leydig-produce testosterone.
What are the 3 sections of the epididymis?
Head (caput), body (corpus), tail (doubles back as vas deferens).
What glands are only found in male cats, not dogs and what is their function?
Bulbourethral (Cowper’s) glands. Like the prostate, make contribution to seminal fluid.
What is the glans penis?
Distal end of penis. Urethral fossa protrudes slightly with urethral opening central.
What is the function of the vas deferens?
During ejaculation, sperm and fluid produced in seminiferous tubules propell along epididymis and up the vas deferens which joins with the urethra.
What is the epididymis?
Long convulated tube which connects efferent ducts of testes to vas deferens.
Give 3 functions of the oestrous cycle.
Produce ova, prepare tract to receive ova, initiate behavioural patterns, stimulate female to stand still and allow mating.
What is the placenta and what is its function?
Temporary organ made up of veins and embryonic tissue. Allows nutrient uptake, thermoregulation, waste elimination and gas exchange.
What is the prostate gland?
Bi-lobed and lies on the floor of the penis, surrounding the urethra. Like the bulbourethral glands, it makes a contribution to seminal fluid.
What is the prepuce?
Covers and protects, lined with a mucous membrane, and is well supplied with lubricating glands. Pushed back during mating to reveal the glans penis.
What is the os penis?
Tunnel shaped bone within the glans penis which aids in the entry of the vagina during early mating when erection is only partially complete.
What is the purpose of seminal fluid?
Increases the volume of ejaculate, provides the correct environment for the sperm and neutralises the acidity of urine.
What 8 bones make up the forelimbs?
Scapula, clavicle, humerus, radius, ulna, carpal bones, metacarpal bones, phalanges
What 8 bones make up the hindlimbs?
Pelvis, femur, patella, tibia, fibula, tarsal bones, metatarsal bones, phalanges
What are the 3 components of the skull?
Cranium, nasal cavities, jaw
What are the 4 components of the axial skeleton?
Skull, vertebrae, ribs, sternum
Where is the thymus located, and what is its function?
Below thyroid gland, beneath the sternum. Promotes the development of T-lymphocytes. Also produces hormones that promote growth and maturation.
What is the pituitary gland also known as and what are its two sections?
Known as the master gland, made up of the anterior and posterior pituitary glands
What 3 hormones are released by the thyroid gland?
Thyroxin (T4), tri-iodothyronine (T3), thyrocalcitonin
What 2 hormones are stored in the posterior pituitary gland?
Anti diuretic hormone, oxytocin
What 7 hormones are secreted by the anterior pituitary gland?
FSH, ACTH, Somatotrophin, TSH, LH, ICSH, Prolactin (FASTLIP)
What hormone is secreted by the parathyroid gland and what does it do?
Parathormone, stimulates calcium reabsorption from bones and promotes calcium uptake
List the 5 sections of the vertebrae in order from head to tail.
Cervical, thoracic, lumbar, sacrum, coccygeal.
Provide the function of the layers of the heart.
Myocardium-muscle layer. Pericardium-serous sac that surrounds the heart to protect it and keep it in place. Epicardium-lines the outer layer of the heart. Endocardium-lines the inner walls of the heart
What’s the difference between arteries, veins, and capillaries?
Arteries-oxygenated blood, carry blood away from the heart. Veins-deoxygenated blood, carry blood towards the heart. Capillaries-thin walled, link arteries and carry either oxygenated or deoxygenated blood
What are the three structures of the hindbrain?
Cerebellum, pons, medulla
What are the three structures of the forebrain?
Thalamus, hypothalamus, cerebral cortex
What is the purpose of the midbrain?
‘Net’ of neurons which make up the reticular formation which receives and transmits motor and sensory info, deciding what you’re aware of such as your nose in your view
What are the 4 different nerves in the peripheral nervous system?
Sensory, motor, autonomic, glia
What’s the difference between afferent and efferent nerves?
Afferent nerves (sensory) carry impulses to the central nervous system from the peripheral nervous system. Efferent nerves (motor) carry impulses from the central nervous system to the rest of the body
Give 2 examples of body functions controlled by autonomic nerves.
Heart rate, blood pressure, digestion, thermoregulation
What is synaptic transmission?
How messages are sent- a neurotransmitter (chemical) between two nerves allows electrical impulses to cross to the next nerve
What is the voluntary nervous system?
Part of the PNS, including sensory and motor nerves, transmits info from external stimuli and receives info from the central nervous system, telling us to move AKA somatic nervous system
What is the autonomic nervous system?
Includes autonomic nerves, which provide involuntary control of certain functions. Includes the sympathetic and parasympathetic nervous systems
What is the sympathetic nervous system?
Fight, flight, or freeze-causes an increased heart rate, respiratory rate, and flow to muscles and reduced digestion, excretion and urination
What is the parasympathetic nervous system?
Allows you to relax and return to normal after a fight, flight or freeze response. Causes reduced heart rate and more efficient digestion and bowel movements
What are the three structures of the outer ear (in most species)?
Pinna, ear canal, tympanic membrane
What are the three auditory ossicles and what are they also known as?
Malleus, incus, stapes. AKA hammer, anvil, stirrups
What is the function of the cochlea?
Spiral shaped membrane, picks up vibrations and converts them into electrical signals
What is the function of the organ of corti?
Hair like structures along the corti bundle together at the end of the cochlea to form the cochlea nerve which sends impulses to the brain
What is the function of the soft palate?
Closes off the airway during swallowing
What is the external structure of the nose?
External nares (nostrils) surrounded by rhinarium (nose pad) leading to nasal chambers, separated by cartilaginous septum and filled with fine scrolls of bone called ethmoturbinates.
How do animals smell?
Chemicals responsible for smell, they dissolve in the mucous of the nasal cavity. Sensory nerve fibres carry the sensation to olfactory bulbs
What is the vomeronasal organ also known as?
The Jacobson’s organ
What is the function of the Jacobson’s organ?
Lined with olfactory mucosa, carries info via olfactory nerve which travels to accessory olfactory bulb and then to the hypothalamus which contains sensory chemoreceptors-Causes flehmen response/Bruce effect
What is the sclera?
Fibrous connective layer, holds the shape of the eye (the white of the eye)
What is the cornea?
Fibrous connective tissue, allows proper focus on light-window like and avascular (no blood vessels)
What is the ciliary body?
Muscle ring which surrounds the lens and controls its shape. Suspensory ligaments hold the lens in place
What is the iris?
Smooth coloured muscle, can contract and expand
What is the pupil?
Opening in the iris, allows light through, changing shape to allow more or less light in (small in bright, larger in low)
What is the lens?
Made up of collagen, along with specialised elongated cells and epithelium. Projects light and focusses light onto retina. The lens can change shape and focus appropriately
What is the choroid?
Vascular layer of the eye, supplies the eye with blood, providing nutrition
What is the retina?
Nervous tissue, takes up 2/3 of eye. Absorbs light, creates electrical impulses/messages and sends them to the brain
What’s the difference between rods and cones?
Rods are responsible for night and peripheral vision. Cones provide detailed vision and colour perception
Where are most cones found?
The fovea, a natural depression on the surface of the eye, defines the centre of the retina and is the region of the eye with the highest visual activity
What is the optic disc?
Ganglion cell axons leave the eyeballs here. All photoreceptors and accessory cells are pushed aside so the axons can penetrate the choroid and the sclera. It creates a hole in vision, a blind spot which is covered by the other eye
What are optic nerves?
Carries visual messages from the retina to the brain
What are the three layers of the skin?
epidermis, dermis, subcutaneous/hyperdermis
Give 3 examples of special senses.
Platypus bill, lateral line, vibrissae, electroreception, jacobsons organ, echolocation
Provide 2 functions of the lymphatic system
Return excess fluid to circulation (circulatory), filter out foreign materials such as bacteria, produce lymphocytes (immunity), transport digested fats (digestion)
Name the three lymphatic organs.
Spleen, thymus, tonsils
What is the name for the lymph nodes found in the neck?
Submandibular lymph nodes
What is the function of the lymph nodes?
Destroy and remove bacteria via lymphocytes and filter foreign bodies from the lymph (fluid)
What cells can be found in the lymph nodes, which are responsible for the filtering of lymph?
Phagocytic cells
Where is erythropoietin produced and what is its function?
Produced in kidneys in response to hypoxia (low oxygen). Stimulates erythropoeitis in bone marrow
What structure within the kidneys is responsible for filtering blood?
Nephrons
What happens if an animals kidneys do not function properly?
Harmful toxins build up in the animals body, causing lethargy, vomiting, and anorexia
What’s the main difference between bronchi and bronchioles?
When the cartilaginous tissue disappears, brochi become bronchioles
What is the function of the alveoli?
Gaseous exhange
What two structures within the ears are responsible for balance?
Semi-circular canals and the otolith organs
What is the eustachian tube?
Connects the middle ear to the back of the throat. Opens during swallowing to allow air into the middle ear, making the pressure on either side of the tympanic membrane the same
Describe what happens during pro-oestrous.
Presence of bloody discharge, FSH released to stimulate the maturation of follicles and the production of oestrogen.
Describe what happens during oestrous.
Ovulation occurs, FSH levels decrease and LH levels increase, causing the Graafian follicles to rupture.
Describe what happens during metoestrous and dioestrous.
Formation of the corpus luteum, producing progesterone, still detectable oestrogen but levels will decrease unless pregnancy occurs. The corpus luteum then decreases in size and stops producing progesterone.
What is the name for the lymph nodes found in the armpit area?
Axillary lymph nodes
What is the name for the lymph nodes found in the upper thigh?
Popliteal lymph nodes
What’s the difference between positive and negative feedback mechanisms?
Positive feedback amplifies a changing condition, stimulating (e.g. contractions during birth), negative feedback returns a changing condition back to its target set point, preventative (e.g. blood glucose levels).
What is pyometra?
An infection of the uterus, usually caused by E.coli
What are the two sinuses?
Frontal and maxillary
Where are alveoli contained within the lungs?
Alveolar ducts
What is the pulmonary pleura?
A serous membrane that covers the lungs, enclosed in the plural cavity and contains nothing but a vacuum and serous fluid. Essential to provide smooth movement between the lungs and thoracic wall.
What are the five components of the lymphatic system, not including lymphatic organs?
Lymphatic vessels, lymphatic capillaries, lymphatic ducts, lymphatic tissues, lymph nodes
What is the function of plasma?
Mainly made of water and surrounds the blood cells, carrying them around the body. Helps maintain blood pressure and regulates body temperature.
What is the function of purkinje fibres?
Located in the endocardium, involved in contraction of the heart and a last minute pace maker
Describe the structure and function of the spinal cord.
A long bundle of nerves, protected by the vertebrae. Surrounded by cerebrospinal fluid, acting like a cushion, providing nutrients to the spinal cord and removing waste. Acts as a highway for messages.
What is the function of the cerebellum?
Controls coordination, balance, and movement
What is the function of the pons?
Plays a part in controlling respiration, signals travel along this into and out of the brain
What is the function of the medulla?
Maintains autonomic functions such as heart rate and digestion
What is the function of the hypothalamus?
Links the central nervous system and the endocrine system. Responsible for the homeostasis of temperature, heart rate etc.
What is the function of the cerebral cortex?
Contributes to alertness, intelligence, memory and temperament
