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Male reproductive cells are called _____
sperm
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Sperm are _______ than female sex cells and can ____.
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Sperm ___ have a food store
dont
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Female reproductive cells are called ___ cells
egg
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Eggs are ______ than sperm and _____ move by themselves.
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Eggs ____ a food store
have
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Fertilisation takes place when one male _____ fuses with one female _____. A fertilised ___ is produced.
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For fertilisation to occur the sperm must be able to _____ the egg
reach
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In fish the females lay their ____ in the water and the males deposit their ____ sperm next to the eggs. This is known as _______ fertilisation because it takes place _______ the female's body.
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________ fertilisation takes place inside the female's body, therefore the sperm must be _____ inside the female's body.
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Internal fertilistion is important to land-living animals because there is no ______ environment into which eggs and sperm can be released.
watery
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In animals that use internal fertilisation, the male produces a liquid containing sperm which is ________ inside the female's body during ______
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Sperm are produced in _____
testes
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During mating the sperm pass along the _____ ____ to the penis, which deposits the sperm inside the female's body.
sperm duct
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Eggs are produced in the ____ and are released into the ______.
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The embryo develops in the _____
uterus
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Sperm enter the female's body via the ______
vagina
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After fertilisation the fertilised egg develops into an ______
embryo
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In fish the fertilisation egg is protected by a _____ _______ and the embryo obtains its food from the enclosed ___
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In mammals fertilisation occurs in the ______
oviduct
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The fertilisated egg passes down the oviduct to the uterus where it becomes attached to the ____ of the ______.
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As the embryo continues to develop, a fluid-filled bag called the ______ ___ protects it.
amniotic sac
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The embryo receives nutrients from its mother's _____
blood
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Blood coming from the embryo to the placenta carried waste substances like _______. These waste substances pass into the mother's _____ and are carried away.
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Oxygen and digested food pass into the embryo's blood from the mother's blood in the ________
placenta
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In fish, the young are born with a ____ ___ attached, which they use for food until they can find their own. They _____ receive any parental support.
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When young mammals are born, they are ________ on their parents at first for care and protection. Their mothers provide them with ____
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The ______ the degree of care and protection provided by parents, the _____ eggs and young need to be produced.
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In animals like fish, parents provide very _____ care or protection during the processes of fertilisation and development.
little
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Fish must produce ____ eggs to ensure that enough are fertilised and that enough young survive to keep the species from becoming ______
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In mammals parents provide ____ care and protection, so _____ eggs and young need to be produced.
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