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Human Biology and Evolution Humans are Alive The earliest human life form can
be traced back more than 3.5 billion years ago. Humans are said to be
descendants of a single celled ancestor. Although they are different in size and
shape all basic functions are alike. The more complex the organization of the
cell became the more successful and developed it became. As these single celled
organisms developed they became known as pre-humans. We share many
characteristics with these pre-humans. Some of these characteristics include the
masters of heredity DNA and RNA as well as proteins composed of amino acids,
membranes or bound cells and lastly controlled cell division or mitosis, key to
the daughter cells. Kingdoms are Alive The diversity of kingdoms is arranged
into kingdoms that classify organisms from simple to complex. The traditional
five kingdoms are Prokaryote, Protoctista, Fungi, Plantae, and Anamalia.
Prokaryote is a bacterium that lacks nuclear membrane. Protoctista is a
heterogeneous grouping that combines a great diversity of forms. Fungi are known
for being important agents of composition they include yeast and mushroom.
Plantae, are categorized as plants that use sunlight to convert to energy.
Lastly Anamalia, Anamalial members are multicellular and fully mobile, they
obtain their nutrients from other living things. Our Place in Nature Humans are
hierarchically classified into a series of increasingly specific groups. They
range from the Kingdom Animalia to the Genus Homo, the Homo Sapiens appears to
be its only living representative Kingdom: Animalia Phylum: Chordata Subphylum:
Vertabrata Class: Mammalia Family: Hominidfae Genus: Homo Our Place in time Over
a considerably large span of geological time life on earth has changed
drastically. Humans and their close relatives are the most recent arrivals in
the Tertiary period. The periods range Precambrian which was over 56 million
years ago to Quaternary which was 1.8 million years ago to present. In this
chart you will be able to see all periods ranging from Precambrian to
Quaternary. TABLE PERIOD AGE (MILLIONS OF YEARS) SOME IMPORTANT EVENTS IN THE
HISTORY OF LIFE Quaternary 0.01 1.8 Historic time ice ages; humans appear
Tertiary 5 65 Apelike ancestors of humans appear major radiation of mammals,
birds, and pollinating insects Cretaceous 144 Flowering plants appear; dinosaurs
and many groups of organisms become instinct at end of period Jurassic 208
Gymnosperms continue as dominant plants; dinosaurs dominant; first birds
Triassic 245 Gymnosperms dominate landscapes; first dinosaurs and mammals
Permian 286 Radiation of reptiles; origins of mammal-like reptiles and most
modern orders of insects Carboniferous 360 Extensive forests of vascular plants;
first seed plants; origin of reptiles; amphibians dominant Devonian 408
Diversification of bony fishes; first amphibians and insects Silurian 438
Diversity of jawless vertebrates; colonization of land by Plants and anthropods;
origins of vascular plants Ordovician 505 First vertebrates (jawless fishes);
Marine algae abundant Cambrian 544 Origin of most invertebrate phyla; Diverse
algae Precambrian 700 4600 Origin of first animals Approximate origin of the
earth Biosystem’s the Movie I viewed a video illustrating the senses through
modern dance. The video was very graphic and detailed and showed a virtual tour
of the organs. First I observed how deoxidized blood travel through the heart
chambers to the lungs to get oxidized this was done through the cardiovascular
system.
Then I observed three parts of the nervous system, the ear, eye and the
brain. I then took a tour through the urinary system, the digestive system,
respiratory system and finally the musculoskeloton system, which concluded the
film. Humans are Vertebrates Humans are placed in the subphylum vertebrata. The
category vertebrata contains all animals with a backbone. This group contains
diverse animals such as fish, amphibians, reptiles, birds and mammals. Most of
our familiar body systems are shared with vertebrates. Musculoskeletal System A
skeleton family of four and a dog in a living room watching baseball illustrated
the musculoskeletal system. The baseball game was actually an informational
video on the joints and muscles of the upper body. Circulatory System The
circulatory system has three main components, the lymphatic system, capillaries
and blood.
The lymphatic system transports intercellular fluid through the
circulatory system. Capillaries are microscopic blood vessels whose wall is only
one cell in thickness. They carry blood opulent in oxygen and nutrients to all
tissues in the body. Urinary System The kidney in the urinary system regulates
the chemical composition of the blood thus also regulating the chemical
composition of the body tissues. The functional unit of the kidney is known as a nephron and it absorbs much of the soluble nutrient molecules, certain mineral
ions and some water. This mixture is also referred to as urine. The urinary
bladder then collects this urine from the ureter and stores it for periodic
excretion from the body. Endocrine System The endocrine system consists of a
number of discrete glands located on various points in the body. The endocrine
glands lack ducts, therefore they “communicate” amongst each other chemically.
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