Past exam questions Flashcards
The testes produce the hormone testosterone, which has the following
functions?
1.Development of male secondary sexual characteristics, such as
beard, pubic hair, deep voice and a muscular body.
2. Stimulates the maturation of sperm cells.
Name the accessory glands of the male reproductive system and
give ONE function of each.
-Seminal vesicle which produces a fluid that contains nutrients for the sperm cells, so that they have energy to swim.
-Prostate gland produces an alkaline fluid that neutralises
acids produced in the vagina, so that sperm cells are
protected.
Cowper’s gland produces mucus that helps with the
movementof sperm cells.
Explain the role of the nucleus of the sperm cell in fertilisation
The nucleus contains 23 chromosomes (n), and fuses
with the nucleus of an egg cell, which also contains 23
chromosomes (n). The result is a zygote with
46 chromosomes (2n).
Name all the parts of the sperm cell that are responsible for
movement. State what the function of each part is.
Mitochondria provide energy for swimming.
Tail moves in a whip-like fashion to propel the sperm cell
forwards.
DNA replication occurs during …
interphase
The structure in the ear that equalises the pressure on either side of the eardrum
Eustachian tube
Measurement of the total amount of carbon dioxide emissions of an individual, a defined population or a company per year
carbon footprint
The type of pollution caused when water is released into a river after being heated in power stations or industries
thermal pollution
The watery fluid that supports the cornea and the front chamber of the eye
aqueous fluid
The hormone produced by the Graafian follicle
oestrogen
The hormone responsible for the formation of the corpus luteum
luteinising hormone
The receptors in the ear that detect changes in the direction and speed of any movement of the body
cristae
hormone which stimulates the secretion of thyroxin
thyroid stimulating hormone
The type of fertilisation associated with viviparous reproduction
internal
The series of changes that take place in the shape of the lens and the eyeball in response to the distance of an object from the eye
accomodation
Name the process by which male gametes in humans are formed through meiosis.
spermatogenesis
describe mendels law of segregation
for each allele received you will get one characteristic
Name TWO processes occurring during the 1st meiotic division that contribute to the genetic variation of cells
random assortment of chromosomes and crossing over
what is the function of the epididymis
store sperm cells
what are the consequences for reproduction of the sperm duct is damaged
-Sperm cells will not pass to urethra to fertilize the egg
and hence he will not be able to have children
Explain why it would still be possible for an HIV positive man to infect another person during sexual intercourse after the sperm duct is surgically cut.
The HI virus may still be passed on during sexual intercourse
through the secretions of the accessory glands
Describe how the different parts of the ear and brain allow for hearing to occur.
Sound waves are directed by the pinna
- through the auditory canal
- to the tympanic membrane/ eardrum
- causing it to vibrate
- The vibrations of the tympanic membrane are transferred to the ossicles in
the middle ear
- which eventually causes the oval window to vibrate
- This sets up pressure waves in the perilymph
- Pressure waves are then transferred to the endolymph in the cochlea
- This stimulates the Organ of Corti
- in the cochlea
- to convert this stimulus into a nerve impulse
- *which is then transported along the auditory nerve
- *to the cerebrum
- *where the sound is interpreted
What is a reflex action?
A reflex action is a rapid, automatic response to a stimulus
State the significance of the functional connection at the synapse.
It ensures that the impulse moves in one direction only
Name TWO hormones that have the opposite effect to that of insulin.
Adrenalin and glucagon
Define homeostasis.
the process by which the human body is able to maintain a constant internal enviroment
