Biology written exam part 3 Flashcards
(34 cards)
Which is the first line of defense (immune system)?
- The skin
- Mucus lining
What is active immunity?
is due to the production of antibodies by the organism, after the body´s defenses have been exposed to antigens (natural or by injections)
What is passive immunity?
gained antibodies from another source than the own body (e.g. from mother to child via injection)
What is the role of Antigen-presenting- cells (APC-cell)?
their role is to engulf foreign particles present fragments of these antigens on their surface as flags so that they can be recognized by T-cells
What happens first to pathogens when they enter the body?
When a pathogen enters the body it is phagocyted by a macrophage, digested and antigen-proteins from it are placed on the surface of the macrophage = antigen presentation
What is the function of the urinary sistem?
The urinary tract is the body’s drainage system for removing urine, which is composed of wastes and extra fluid. In order for normal urination to occur, all body parts in the urinary tract need to work together in the correct order
What is the function of the kidneys?
The kidneys are two bean-shaped organs, each about the size of a fist. They are located just below the rib cage, one on each side of the spine. Every day, the kidneys filter about 120 to 150 quarts of blood to produce about 1 to 2 quarts of urine.
What is the function of the Ureter?
Ureters are the thin tubes of muscle—one on each side of the bladder—that carry urine from each of the kidneys to the bladder.
What is the function of the Bladder?
The bladder, located in the pelvis between the pelvic bones, is a hollow, muscular, balloon-shaped organ that expands as it fills with urine. Although a person does not control kidney function, a person does control when the bladder empties. The bladder stores urine until the person finds an appropriate time and place to urinate. A normal bladder acts like a reservoir and can hold 1.5 to 2 cups of urine. How often a person needs to urinate depends on how quickly the kidneys produce the urine that fills the bladder. The muscles of the bladder wall remain relaxed while the bladder fills with urine. As the bladder fills to capacity, signals sent to the brain tell a person to find a toilet soon. During urination, the bladder empties through the urethra, located at the bottom of the bladder. There are 3 sets of muscles involved in this process.
How does the transmission of information in the nervous system work?
- Nerve impulses from the receptor cells, sensory neurons, are send to the central nervous system with the help of neurons.
- The dendrites receive the neurotransmitters by endocytosis and send the impulse further to the axon and then to the end plates of the neuron.
- At the endplates calcium ions are entering the endplates, which pushes the vesicles with the neutron transmitters to be releases at the synapse by exocytosis.
What is the role of the brain?
Much of the brain’s job involves receiving information from the rest of the body, interpreting that information, and then guiding the body’s response to it. E.g. pain, light, sound and blood pH etc
What is the function of the cerebrum?
It handles memory, speech, the senses, emotional response, and more. It is divided into several sections called lobes
What is the function of the cerebrellum?
It controls motor function, the body’s ability to balance, and its ability to interpret information sent to the brain by the eyes, ears, and other sensory organs.
What is the function of the hypothalamus?
is the part of the brain responsible for hormone production. The hormones produced by this area of the brain govern body temperature, thirst, hunger, sleep, circadian rhythm, moods, sex drive, and the release of other hormones in the body. This area of the brain controls the pituitary gland and other glands in the body.
What are the types of sensation in humans?
- Smell
- Taste
- Feel (sense)
- Hear
- sight
What is the function of the cornea?
helps focus the light that enters the eye
What is the function of the iris?
controls the amount of light that enters
What is the function of the Pupil?
dim light the pupil is wide open so as much light as possible enters while in bright light the pupils contract to protect the retina from damage by excess light
What is the function of the lens?
bends the light
What is the function of the aqueous and vitreous humours?
maintains the shape of the eyeball and help press the retina firmly against the choroid so clear images are seen.
What is the function of the blind spot?
there are no rod and cone cells, see nothing
What is the function of the obtic nerve?
send the information of the eyes to the brain
What is the function of the Fovea?
the area of sharpest vision
What is the function of the sclera?
is a tough fibrous layer that protects the eyeball and gives it rigidity
