Lab #3

Our bodies want to make ________.

Around the world, about ________ new babies get made every day.

From a _______ ____, you built a body that has 100 trillion cells.

At least some blame for the urge to reproduce can go to this...._____.

If humans were all clones, we'd have the exact same ______ ______ and one successful parasite could wipe us all out. Fortunately, there's ____.

When there's sex, there's ________ and when it comes to survival of the fittest, ______ has a definite advantage.

The tubes in the testes can stretch out to cover ___________. What are they called?

A man can produce ______ new sperm every second, 100 million every day, 2 trillion over a lifetime.

Each sperm is carrying a unique ______ package.

How does this genetic activity happen? By a process called _______.

We have _______ genes spread out over 46 chromosomes.

The more _______, the better the odds are that someone will survive to create a new generation.

Melinda created _______________ when she was a fetus in her mother's womb.

At the age of 31, she may only have a few __________ eggs left.

The egg is swept along the felopian tube by muscular contraction and the action of ______.

If the egg is not fertilized within a few _____, it will die.

The sperm travel along a ___ inch tube looping into the abdomen and penis.

The semen is only about a teaspoon but contains ____ million sperm.

Even in a healthy man, ___% of sperm are less than perfect.

For a few days a month around ovulation, the mucus plug over the cervix becomes ______.

It is estimated that ____% of all fertilized eggs fail to develop.

About 5 days after fertilization, the dividing cells arrive in ______, about 100 small cells trapped within the zona.

The Blastocyst burrows into the uterine lining searching for ______________.

2 weeks after conception, the blastocyst is the size of a _________.

Gastrulation is the process of the blastocyst changing into an _______.

3 weeks after fertilization, the embryo is less than a ___th of an inch.

At 4.5 weeks the embryo is 1/5 of an inch long, has a ___, a large developing brain and eye.

If all DNA in a single cell were unwound, it would be __ft long.

At 7 weeks old, boy and girl embryos look ________, inside and out.

A gene on the Y chromosome called ____ turns on for a day or two setting off a chain of events leading to testes.

2 months after fertilization, the embryo now called a _____, is just over an inch and less than a third of an ounce.

The Placenta's underside has 1000's of _____ which lie in pools of the mom's blood.

(true/false) The mother's blood normally never mixes with the blood of the fetus.
True False

The fetus's heart beasts _____ as fast as adults.

Most of the bones in the fetus start as __________.

After 5 months the fetus can ____.

At week 8 the fetus is ___ inch long with fingers and toes. At 12 weeks it is 3 inches, at 16 weeks it is 5 inches.

During the last __________, all organs are in place and they mostly need to grow.

During the 6th month, genes order the manufacture of a fatty covering for the neurons called _______.

Human births are far more dangerous due to the brain being 3x larger than other primates and humans have a ______ pelvis for walking.