The start of the 20th century was the continuation of the Restoration, which began when Alfonso XII became king in 1874. Alfonso XII died in 1885.
Alfonso XII and his second wife María Cristina. By F. Barcia Viet. Sevilla (Los Borbones) [Public domain], via Wikimedia Commons
Spain was ruled by his wife María Cristina until Alfonso XIII turned 16 in 1902.
Alfonso XIII. By Christian Franzen [Public domain], via Wikimedia Commons.
During Alfonso XIII's reign Spain experienced political and social conflict.
The Liberals and Conservatives continued to take turns in government. Republican parties, the Socialist party and nationalist parties in Cataluña and Pais Vasco opposed them.
There were many strikes, workers demanded better working conditions.
Spain was involved in military conflict in its new colonies in Morocco.
In 1923 there was a military coup. General Primo de Rivera established a dictatorship with Alfonso XIII's support:
The constitution was suspended, the king lost most of his powers.
Political parties became illegal.
Freedom of press was limited by censorship.
Alfonso XII y Miguel Primo de Rivera. Bundesarchiv, Bild 102-09411 / Unknown / CC-BY-SA 3.0 [CC BY-SA 3.0 de (http://creativecommons.org/licenses/by-sa/3.0/de/deed.en)], via Wikimedia Commons
At first Primo de Rivera was supported by many people. Later on he had the opposition from the army and from Alfonso XIII. Primo de Rivera resigned in 1930.
In 1931 the Republicans and the Socialists won the municipal elections and the Second Republic began. Manuel Azaña became president.
Medical advances can help at specific stages of reproduction. Fertilisation: In-vitro fertilisation is a procedure that involves joining the male and female reproductive cells outside the woman's body, in a laboratory. If fertilisation occurs, the zygote is placed inside the woman's uterus.
Birth: one of the problems which can occur during birth is the breech birth, doctors usually perform a Cesarean section. They extract the fetus through a small cut they open through the lower abdomen and the wall of the uterus, instead of through the mother's vagina.
Click on this photo to watch a video about Cesarean Section.
Pregnancy: during pregnancy specialist doctors check the mother and the fetus health. They analyse blood and urine samples to detect infections in the fetus. To detect problems (abnormalities) in the fetus, doctors analyse amniotic fluid extracted from the amniotic sac. This procedure is known as amniocentesis. They also use an ultrasound scan to check the developing organs and bones in the fetus and its growth as well.
A man and a woman have sexual intercourse. The man deposits his semen in the woman's vagina. The sperm cells swim into the uterus and up the fallopian tubes, where one of them will fertilise the female egg cell. When a sperm cell joins with an egg cell in the fallopian tube, they form
a new cell called a zygote(click here to watch a video about fertilisation).The zygote that results goes into the uterus. as it travels, it divides many times to form a group of cells called an embryo, and finally it develops into a fetus.
8 cell embryo at day 3. By ekem, Courtesy: RWJMS IVF Program [Public domain], via Wikimedia Commons.
Fetus 3 months. By National Museum of Health and Medicine [Public domain], via Wikimedia Commons.
PREGNANCY
Pregnancy is the period of time between the fertilisation of an egg cell and the birth of a baby.
The placenta provides the fetus with oxygen and nutrients from the mother's blood. It also takes away carbon dioxide and waste that the fetus produces.
The fetus is connected to the placenta by the umbilical cord.
The amniotic sac contains a liquid called amniotic fluid. This liquid supports
the fetus and protects it.
Placenta and umbilical cord. By Gray38.png: User Magnus Manske on en.wikipedia derivative work: Amada44 talk to me (Gray38.png) [Public domain, Public domain, Public domain or Public domain], via Wikimedia Commons
During birth (click on the word birth to watch a video) the walls of the uterus start to contract.
Then the cervix gets wider to enable baby to come out of the uterus. Next the
amniotic sac breaks and the contractions push the baby into the vaginal canal.
Once the baby is outside the mother's body he starts to breathe and the doctor cuts the umbilical cord. Finally the amniotic sac, the placenta and the rest of the umbilical cord are expelled.
During puberty a girl's ovaries start to release eggs. every 28 days a mature egg cell is released from one of the ovaries, it travels down a fallopian tube to the uterus. It stays here for some days waiting to be fertilised. If the egg is not fertilised it leaves the body with blood and tissue. This is called the menstrual cycle.
The female reproductive system is formed by external sex organs and internal sex organs (located inside the pelvis).
The ovaries produce egg cells. There is one ovary on each side of the uterus.
The uterus is where a fertilised egg cell develops into a fetus.
The fallopian tubes connect the ovary with the uterus. The egg cell travels along them.
The cervix is the narrow part of the uterus that leads to the vagina.
The vagina is a muscular canal that leads from the vulva (the external organ) to the uterus.
Female Reproductive System, by CDC, Mysid [Public domain], via Wikimedia Commons
There are two types of human reproductive cells which are called gametes: the female egg cell (ovum) and the male sperm cell (spermatozoon). A female egg is round and much larger than a sperm cell. A sperm cell has a small head and a long tail which helps it to move around.
Egg cell, Henry Vandyke Carter
[Public domain], via Wikimedia Commons
Sperm cells, By Bobjgalindo (Own work) [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC BY-SA 4.0-3.0-2.5-2.0-1.0 (http://creativecommons.org/licenses/by-sa/4.0-3.0-2.5-2.0-1.0)], via Wikimedia Commons
Sperm cell and egg cell fusing, via Wikipedia.
Reproduction can be sexual or asexual.
In sexual reproduction the male and the female gametes combine to produce a fetus and contains DNA from each one.
The differences between male and female bodies are called sex characteristics. Primary sex characteristics are the differences between the male and the female reproductive organs. Secondary sex characteristics aren't directly related to reproduction (facial hair...).
