A sac containing the testes.
what does blood do to the penis?
It causes an erection.
How many eggs does the female ovary contain?
2 million egg cells
How many sperm does a male typically produce daily?
several hundred million
The male sex hormone.
A common viral STD
What penetrates an egg?
During fertilization, enzymes at the tip of the head of the sperm help penetrate it.
Where are sperm produced?
In the testes and seminal vesicles.
Where are mitochondria located?
In the midpeice of the sperm.
After puberty, how many and how often are eggs produced?
Only one is produced and about every month.
Is what a developing human is called from 8 weeks till birth.
where are sperm cells never found?
what is the structure specialized for fetal development?
What is the period of time from zygote formation till birth?
What is the Endocrine gland?
a ductless glass that secrete into the blood stream.
Adrenal glands are located where?
Above the Kidneys
what changed the early atmosphere by giving off oxygen?
the determining of the age of a rock.
what was amino acids gathered into , which was the first step to cellular organization?
Organisms safely lived on land after what?
After the ozone formed.
what was the major structure change that made living on land possible
Prokaryotes that lack peptidoglycon in their cell walls are called what?
3 successful kingdoms that evolved from protists.
Fungi, plants, and Animals
First vertebrates on land.
What did reptiles evolve from?
Evolution occurs from what?
Strong evidence of evolution occurs from what?
is a source of evolution
why are fossils often used as evidence of evolution?
it shows how organisms change with he passage of time.
What may geographic isolation lead to?
Divergence and speciation.
The passageways throught which the ovum travels
A series of divisions which the zygote goes through in the first week of fertilization
Estrogen and Progesterone
The female sex hormones
six days after fertilization, the blastocyst burrows into the uterine lining.
A sexually transmitted disease can be treated and cured with antibiotics if they are what?
caused by Bacteria
Why was ozone imprtant in enabling organisms to live on land?
It protects us from ultraviolet radiation.
What was the first multi-cellular organisms to colonize the land?
What is the Endosymbiotic theory?
the theory that proposes how eukaryotic cells arose from prokaryotic cells. mitochondria and chloroplasts was thought to be prokaryotic cells at one time.
Larger prokaryotic cells engulfed mitochondria and chlroplasts and the formed mutualistic relationship resulting in out first eukaryotic cells.
Where the sperm matures and become mobile.
vas deferens and the scrotum
where sperm are deposited in the female system by.
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