May 25, 2018

Biology: Birds

What Is a Bird?
Source: Wikipedia
A bird is an endothermic vertebrate that has feathers and a four-chambered heart, and lays eggs. Birds have scales on their feet and legs, most birds can fly.

The bodies of birds are adapted for flight.
The bones of a bird's forelimbs form wings. Many of a bird's bones are nearly hollow.
Flying birds have large chest muscles that move the wings.
Feathers are a major adaptation that help birds fly.

Feathers

Source: Bird Academy
Feathers are a major adaptation that help birds fly.

A contour feather is one of the large feathers that give shape to a bird's body. The long contour feathers that extend beyond the body on the wings and tail are called flight feathers. When a bird flies, these feathers help it balance and steer.

Down feathers are specialized to trap heat and keep the bird warm. Down feathers are found right next to a bird's skin.
Down feathers are soft and flexible.

Food
Source: dixonapbio-taxonomywiki-2016
Birds have no teeth. To capture, grip, and handle food, birds primarily use their bills.

Many birds have an internal storage tank, or crop, that allows them to store food inside the body after swallowing it.

Delivering Oxygen to Cells

Birds have a system of air sacs in their body that connects to the lungs. The air sacs enable birds to extract much more oxygen from each breath of air than other animals can.

Birds have hearts with four chambers - two atria and two ventricles.

Nervous System and Senses

In order to fly, birds must have very quick reactions

A bird can react quickly because of its well-developed brain and finely tuned senses of sight and hearing.

Diversity of Birds

In addition to adaptations for flight, birds have adaptations - such as the shapes of their legs, claws, and bills - for living in widely diverse environments.

May 24, 2018

Biology: Reptiles

Protection from Drying Out

A reptile is an ectothermic vertebrate that has lungs and scaly skin.

Reptile can spend their entire lives on dry land.

About 7000 kinds of reptiles are alive today, but they are only a tiny fraction of a group that once dominated the land.

The eggs, skin, and kidneys of reptiles are adapted to conserve water.



An Egg With a Shell

A reptile's egg has a shell and membranes that protect the developing embryo and help keep it from drying out. Reptiles lay their eggs on dry land. Reptile eggs are soft and leathery.


Skin and Kidneys

Reptile have dry, tough skins covered with scales. This scaly skin protects reptiles and helps keep water in their bodies.

The kidneys of reptiles concentrate the urine so that they lose very little water.


Obtaining Oxygen from the Air

Most reptiles breathe entirely with lungs.

The hearts of most reptiles have three chambers - two atria one ventricle.


Lizards

Source: San Diego ZOO
Most reptiles alive today are either lizards or snakes.

Both have skin covered with overlapping scales.

They shed their skins and live in warm areas.

Lizards have four legs, usually with claws on the toes.

They have long tails, slender bodies, movable eyelids and external ears.

A few lizards, are herbivores that eat leaves. Most lizards are carnivores that capture food by jumping at it.

Snakes

Source: San Diego ZOO
Snakes are able to live in almost every sort of habitat, from deserts to swamps.

Snakes have no legs, eyelids, or external ears, and most snakes have only one lung.

Snakes move by contracting, or shortening, bands of muscles that are connected to their ribs and back bones.

All snakes are carnivores.

The bones of a snake's skull can move to let the snake swallow an animal much larger in diameter than itself.

Turtles

Source: San Diego ZOO
A turtle is a reptile whose body is covered by a protective shell, which is made from the turtle's ribs and backbone.

The bony plates of the shell are covered by large scales made from the same material as the skin's scales.

The largest turtles are carnivores.


Alligators and Crocodiles

Source: San Diego ZOO
Alligators have broad, rounded snouts, with only a few teeth visible.

Crocodiles have pointed snouts, and you can see most of their teeth. Both alligators and crocodiles spend much of their days resting in the sun or lying in the water.

Alligators have broad, rounded snouts, with only a few teeth visible.

Crocodiles have pointed snouts, and you can see most of their teeth. Both alligators and crocodiles spend much of their days resting in the sun or lying in the water.

Alligators and crocodiles are carnivores that hunt mostly at night.

Unlike most other reptiles, crocodiles and alligators care for their eggs and newly hatched young. For as long as a year, mother stays near her young.

May 22, 2018

Chemia: Kwas Siarkowy (IV)

Source: Chemia - Gimnazjum 
SO₂ + H₂O ⟶ H₂SO₃

Właściwości fizyczne
  • ciecz
  • bezbarwny
Właściwości chemiczne
  • nieorganiczny kwas tlenowy
  • ma właściwości bielące
  • nietrwały - łatwo ulega rozkładowi
  • ma charakterystyczny zapach tlenku siarki (IV)
  • trujący

Znaczenie i zastosowania tlenku siarki (IV)
i kwasu siarkowego (IV)

Przemysł włókienniczy i papierniczy 
Kwas siarkowy (IV) i tlenek siarki (IV) mają właściwości bielące, dlatego kwas siarkowy (IV) stosuje się np. do bielenia wełny i papieru.

Przemysł chemiczny
H₂SO₃ stosuje się do produkcji innych kwasów: HCl, H₃PO₄, HF.

Rolnictwo
Kwas siarkowy (IV) wykorzystuje się do produkcji nawozów sztucznych.

Dezynfekcja
Właściwości bakteriobójcze H₂SO₃ są wykorzystywane w dezynfekcji beczek przeznaczonych do przechowywania wina lub kiszonek oraz pomieszczeń gospodarczych (np. piwnic) i hodowlanych (np. stajni, kurników).

Chemia: Kwas Siarkowy (VI)

Source: Chemia - Gimnazjum 

SO₃ + H₂O ⟶ H₂SO₄

Tlenek kwasowy 
- najczęściej tlenek niemetalu, który w reakcji z wodą tworzy kwas. Wartościowość niemetalu w kwasie i w tym tlenku jest taka sama.

Kwas tlenowy - kwas, którego cząsteczka zawiera atomy tlenu.


Właściwości fizyczne
  • oleista ciecz
  • bezbarwny
  • ma gęstość większą od gęstości wody
  • higroskopijny 
Właściwości chemiczne
  • nieorganiczny kwas tlenowy
  • bezwonny
  • żrący
  • zwęgla substancje organiczne

Zastosowania kwasu siarkowego (VI)

Akumulator ołowiowy
Elektrolitem jest roztwór H₂SO₄.

Przemysł farmaceutyczny
Przy użyciu H₂SO₄ produkuje się wiele leków, np. polopirynę.

Tworzywa sztuczne
Włókno, do którego produkcji wykorzystuje się kwas siarkowy (VI), to jedwab sztuczny. Wytwarza się z niego najdelikatniejsze tkaniny. Trudno je odróżnić od tkanin z jedwabiu naturalnego.

Motoryzacja
Karoserie samochodów przed malowaniem oczyszcza się roztworem H₂SO₄.

Przemysł petrochemiczny
H₂SO₄ jest używany do oczyszczania olejów, nafty i parafiny oraz do osuszania gazów.

Środki czystości
H₂SO₄ stosuje się do produkcji środków piorących i myjących.

May 11, 2018

Chemia: Kwas Siarkowodorowy

Source: Chemia - Gimnazjum
H₂ + S ⟶ H₂S

Właściwości fizyczne
  • ciecz
  • bezbarwny
Właściwości chemiczne
  • nieorganiczny kwas beztlenowy
  • wydziela ostry zapach zgniłych jaj
  • trujący

Zastosowania siarkowodoru i kwasu siarkowodorowego

medycyna 
W uzdrowiskach, np. w Szczawnicy i Krynicy Zdroju, kwas siarkowodorowy jest składnikiem wód leczniczych.

przemysł chemiczny 
Siarkowodór jest stosowany do produkcji siarki.

przemysł kosmetyczny
Kwas siarkowodorowy wykorzystuje się do produkcji depilatorów chemicznych.

laboratoria chemiczne 
H₂S(ag) stosuje się do wykrywania jonów niektórych metali.

May 10, 2018

English: Verbs

Mind Map created by Jas C-W with GoConqr

Biology: Amphibians

Gills to Lungs

Source: National Geographic Kids
An amphibian is an ectothermic vertebrate that spends its early life in water.
Amphibian (double life)

After beginning their life in water, most amphibians spend their adulthood on land, returning to water to reproduce.

Most amphibians lay their eggs in water. Amphibian eggs hatch into larvae that swim and have gills for obtaining oxygen. As they undergo metamorphosis and become adults, most amphibians lose their gills and acquire lungs. Adult amphibians also obtain oxygen and get rid of carbon dioxide through their thin, moist skin.


Amphibian Circulation

Source: Natural History on the Net
The hearts of most amphibians have three inner spaces, or chambers. The two upper chambers of the heart, called atria, receive blood.
From the atria, blood moves into the lower chamber, the ventricle, which pumps blood out to the lungs and body.


Reproduction and Development

Source: Education.com
Most amphibians undergo metamorphosis. Hind legs appear first, accompanied by changes in the skeleton, circulatory system, and digestive system. Later the front legs appear. At about the same time, tadpole loses its gills and starts to breathe with its lungs.

Getting Around on Land

Most adult amphibians have strong skeletons and muscular limbs adapted for movement on land. Amphibians were the first vertebrates to have legs.

Although most tadpoles are herbivores, most adult frogs and toads are predators that feed on insects or other small animals.

May 8, 2018

Biology: Fishes

A fish is a vertebrate that lives in the water and has fins, which are structures used for moving.
Most fishes are ectotherms, obtain oxygen through gills, and have scales.

Nearly half of all vertebrate species are fishes.


Obtaining Oxygen
Source: todayifoundout.com
Fishes get their oxygen from water. The water, which contains oxygen, moves through openings in the fish's throat region that lead to the gills.
As water flows over the gills, oxygen moves from the water into the fish's blood, while carbon dioxide, which is a waste product, moves out of the blood and into the water. After flowing over the gills, water leaves the fish by flowing out through slits beneath the gill covers.

Fishes have a closed circulatory system.
The heart  of a fish pumps blood in one continuous loop - from the heart to the gills, from the gills to the rest of the body, and back to the heart.



How Fishes Reproduce

Source: TES
Most fishes have external fertilization.
The eggs are fertilized outside of the female's body. The male hovers close to the female and spreads a cloud of sperm over the eggs as she releases them.

Internal fertilization, in which the eggs are fertilized inside the female's body. The young fish then develop inside her body.


Fishes Without Jaws
Source: Wikipedia
Biologists classify fishes into three major groups: jawless fishes, cartilaginous fishes, and bony fishes. They are distinguished from one another by the structure of their mouths and the types of skeletons they have.

Modern jawless fishes have no scales. Their skeletons are made of cartilage, and they do not have pairs of fins. Their mouths do not have jaws.
The mouths of jawless fishes have structures for scraping, stabbing, and sucking.

Hagfishes and lampreys are the only kinds of jawless fishes.
Many lampreys are parasites of other fishes.



Cartilaginous Fishes
Source: Wikipedia
Sharks, rays, and skates are cartilaginous fishes.

The skeletons of these fishes are made of cartilage.

They have jaws and pairs of fins. Pointed, toothlike scales cover their bodies.

Cartilaginous fishes are all carnivores.


Bony Fishes
Source: National Geographic 
Most familiar kinds of fishes have skeletons made of hard bone. Their bodies are covered with scales, and a pocket on each side of the head holds the fish's gills.

Most bony fishes have an organ called a swim bladder, an internal gas-filled sac that helps the fish stabilize its body at different depths.

A fish has greater buoyancy when the volume of gases in its swim bladder is large than when the gas volume is small. By adjusting its buoyancy as it moves in the water, a fish can float at different depths without using a large amount of energy.

May 7, 2018

Biology: Evolution of Vertebrates

The Chordate Phylum

Source: Encyclopedia Britannica 
Vertebrates are a subgroup in the phylum Chordata.
Chordates share these characteristics: at some point in their lives, they have a notochord, a nerve cord, and slits in their throat area.
Notochord is a flexible rod that supports the animal's back.

In vertebrates, part or all of the notochord is replaced by a backbone. A few vertebrates have backbones made of cartilage (a connective tissue that is softer than bone, but flexible and strong). Most vertebrates have backbones made of hard bone.

All chordates have a nerve cord that runs down their back.
The nerve cord is the connection between the brain and the nerves.
Chordates have slits in their throat area called pharyngeal slits. Fishes keep these slits as part of their gills for their entire lives, but in many vertebrates, including humans, pharyngeal slits disappear before birth.

The Backbone and Endoskeleton
Source: Slideplayer
A vertebrate's backbone is part of an endoskeleton, or internal skeleton. The endoskeleton supports and protects the body, help give it shape, and gives muscles a place to attach. In addition to the backbone, the vertebrate's endoskeleton includes the skull and ribs. The skull protects the brain and sense organs. The ribs attach to the vertebrae and protect the heart, lungs, and other internal organs.

Maintaining Body Temperature

Most fishes, amphibians, and reptiles have a body temperature that is close to the temperature of their environment. In contrast, birds and mammals have a stable body temperature that is typically much warmer than their environment.

ectotherms (cold blooded)

Source: Sheppard Software's
An animal whose body does not produce much internal heat - fishes, amphibians, and reptiles.

endotherm (warm blooded)

Source: Sheppard Software's
An animal whose body controls and regulates its temperature by controlling the internal heat it produces.
Endotherms also have other adaptations, such as fur or feathers and sweat glands, for maintaining their body temperature.

May 6, 2018

Biology: Echinoderms

The "Spiny Skinned" Animals

SlideShare
An echinoderm is a radially symmetrical invertebrate that lives on the ocean floor. Echinoderm means "spiny skinned".

The skin of most of these animals is supported by a spiny internal skeleton, or endoskeleton, made of plates that contain calcium.
Adult echinoderms have a unique kind of radial symmetry in which body parts, usually in multiples of five, are arranged like spokes on a wheel.

Have an  internal fluid system called a water vascular system.
Consists of fluid-filled tubes within the echinoderm's body.

Echinoderms do not have a head end where sense organs and nerve tissue are found.
They are adapted to respond to food, mates, or predators coming from any direction.

Most echinoderms are either male or female. Eggs are usually fertilized right in the seawater, after the female releases her eggs and the male releases his sperm. The fertilized eggs develop into tiny, swimming larvae that eventually undergo metamorphosis and become adult echinoderms.

Sea Stars

Source: National Geographic Kids
Sea stars are predators that eat mollusks, crabs, and even other echinoderms.

The sea stars grasps a clam with all five arms. Then it pulls on the tightly closed shells with its tube feet. When the shells open, the sea star forces its stomach out through its mouth and into the opening between the clam's shells. Digestive chemicals break down the clam's tissues, and the sea star sucks the partially digested body of its prey.

If a sea star loses an arm, it can grow a replacement. A few species of sea stars can even grow a whole animal from a single arm.

Some sea stars reproduce by splitting into many parts.