6.3 Baby: The First Nine Months and 6.4 Growing Up: Non-Human Animals

Baby: The First Nine Months

   1) When does the baby: (a) begin to move (b) open it eyes (c) begin to kick its mother so that she    notices?
   (a)The baby begins to move at 10 weeks (b) the baby begins to open its eyes at 26 weeks (c) the mother begins to feel the baby's kicks at 18 weeks

   2) When is the baby: (a) as long as a finger nail (b) as long as your foot?
   (a) The baby is about as long as your finger nail by two weeks (b) Babies are about as long as your foot by twelve weeks

   3) Babies which are born early are kept warm in incubators. Why?
       Babies premature need to be kept warm because there mechanism to maintain body temperature is still not functioning and they can't maintain proper body temperature, so they need an incubator

   5) Try to find out: why girls should be given injections to prevent them from getting German measles.
       Girls need to be given the injection before they reach puberty because if given during puberty it is not effective.

6.4 Growing Up: Non-Human Animals

   1) Which two things do all growing embryos need?
       All growing embryos need oxygen and food
   2) How does: (a) frog embryo get the oxygen it needs? (b) a human embryo get the oxygen it needs?
       (a) Frog embryos get their oxygen through the egg (b) A human embryo gets its oxygen through the blood pumped into its body through the umbilical cord
   3) (a) What is the yolk's job in the egg? (b) As the chicken grows, the egg's yolk gets smaller. Why?
       (a) The job of the yolk is to provide food for the growing embryo (b) The yolk gets smaller for two reasons; to make space for the chick, and because the chick has been feeding on it
   4) Make lists of animals which grow: (a) inside their mother (b) inside eggs which  the mother lays
       (a) elephant - human - dog - cat - mouse - whale - dolphin - giraffe
       (b) snake - sea turtle - sparrow - chickens - frogs - crocodile - ostrich - tuna
   5) Which animals produce embryos that grow that grow into larvae?
       Some animals include flies, beetles, frogs, cockroaches and butterflies
   6) Try to find out: how lizard embryos grow
       
       

Dissection of a Flower

Today we dissected a flower to see if we could find and photograph the different parts of the reproductive system, as this would help us visualize and understand how this system worked.

Here we see the female reproductive part, the pistil, and the different parts of it

Here we can see the inside of the ovary, although it it isn't very clear here, this is where the eggs should be

Here we see the male part of the flower, the stamen, where the pollen is produced

here we see the petal, which is a superficial part of the flower that is supposed to attract insects

Light Brainpop Summary

There are two types of light; natural light and artificial light. Artificial light is formed when matter gives off energy in the form of light rays. You can produce artificial light in two ways; 1) by heating something up e.g. the wick of a candle or 2) by running electricity through either a solid like a light bulb filaments or through a gas like neon, to produce light. The other type of light is natural light, and there a few different examples. The sun is a natural source of light, and is basically a ball of flame, which is again light in the form of heat. Some animals are also able to produce their own light through chemical reactions in their bodies. Light sources are emitted in a whole spectrum of radiation, called the electromagnetic spectrum, which is a spectrum of "all the possible frequencies of electromagnetic radiation" (Electromagnetic Spectrum, Wikiedia.org). Light can be thought of in two ways, either in waves with electromagnetic field, or sometimes in discreet packets of energy called photons. Because light is an electromagnetic wave, it can travel through space and does not need a medium to travel through. Light travels at roughly 300 k/s, or 299,792,458 m/s. Light travels in straight lines, but when it hits an object it reflects off, and that is why we can see things.

Light Reflecting off a Mirror

Flames Optical Illusion

This is the optical illusion we did in class, and although it seems that the flame is coming out of my hand, it is actually an optical illusion, we used a Plexiglas screen, and using the properties of mirrors, we were able to create this illusion. I was behind the screen, while the Bunsen burner was on the other side, and, because a reflected image appears the same distance behind the mirror as it is in front, you can move the Bunsen burner backwards or forwards, then the reflection also moves, and you can make the flame look like its coming out of anywhere. This effect has been used in many movies before computer graphics became as famous.

With a mirror what happens is that when light is reflected, it reflects at the same angle it came, and that is why you can see you self in a mirror. Also, because it reflects in this way, the image always seems to appear at the same distance:

Refraction and Diffraction

Refraction and diffraction 2 different properties of waves, that affect all types of waves. Light normally travels in straight a straight line as long as it is going through the same material. Once is begins going through a different material, it refracts, meaning that it bends, because it travels at a different speed through other materials than it does through air, due to the variation in density, and this causes images to appear bent or distorted. To measure this, we measure the angle of refraction, which is the angle at which a color of light is bent when being refracted. Different colors have different angles of refraction. A prism refracts all colors of light at different angles so that you can see them as a rainbow, as well as rain drops on a sunny day. Diffraction, on the other hand, is "the bending and spreading of waves around different obstacles" (Brainpop: Refraction and Diffraction). Diffraction is like radio waves radiating from a television base, or when you talk. The waves don't all travel in a straight line, but instead in all directions, so that they reach different places. Another example of diffraction is the passing of waves through a small hole. The waves on the other side will spread out. If there is more than one one hole, the waves spread out and overlap, creating a predictable interference pattern. Diffraction can be used, for example, to create x-ray images of small objects, or images of very distant ones.

Diffraction

Refraction

Waves Paragraph Summary

All waves do the same thing, transfer energy from one place to another, but there are two types of waves, mechanical and electromagnetic. All waves that need a medium to move through are called mechanical waves. These include sound waves, ocean waves and seismic wave. In mechanical waves, the medium may move but will return to its original position. Waves that need a medium to travel through cannot through travel a vacuum such as space, because they have nothing to move through. These waves work by moving energy from particle to particle, until they reach their destination. Electromagnetic waves, however, such as light, x-rays, and radio waves, do not need a medium to travel through, and can travel through empty space. That is why the sun's rays are able to travel to earth. Although these 2 types of waves are different, they can be measured in many of the same ways. The first type is a transverse wave, which are waves that carry energy by moving at right angles to the direction of the energy flow. Ocean waves, and most electromagnetic waves are have a transverse wave pattern. The highest point of a transverse wave is the crest, while the lowest point is called the trough. The distance between the middle of the wave and the crest is called the amplitude, which is used to measure how much energy the wave has, the larger the amplitude, the more energy the wave is carrying. To find a wave's wavelength, you either measure the distance between two adjacent crests, or to adjacent troughs. Another way of measuring transverse waves is by their frequency, which is the number of waves that pass a certain point in one second, and is usually measured in hertz. The other type of measuring waves is compressional waves, which move my displacing matter back and forth in the direction of the energy flow. Sound travels in this type of wave, by preforming a series of compressions that travel through the air.

Transverse Waves

Compressional Waves

Different Frequencies

The Behavior of Light

22.1 Shadows and Reflections

1. What evidence do you have that light travels in a straight line?

First of all, we can see that the shadow of an object is always in the opposite direction the light is coming from, and always continues with the light in a straight line. As well, light doesn’t bend around corners or stuff.

2.

3. When light is reflected in a mirror, what is special about the angle of the incident and reflected rays?

Their angles to the mirror are the same.

4. Where is the image when you look at something in a mirror?

It appears to be behind the mirror, because of the way light reflects off the mirrior

5. Light travels in straight lines. If you hide just around a corner so that you can’t see your friends, can they see you?

No, as long as you cannot see your friends, they cannot see you because light travels in straight lines, and if you are behind a wall, it will be blocked.

22.1 Reflections by Different Surfaces

1. What can you see in a completely dark room?

Nothing, because there is no light to reflect off anything

2. If you place a lamp in this dark room as a light source, explain how you now see: a) the lamp b) a piece of paper

a) You can see the lamp because it is a source of light, and produces its own light b) there is now a light source that can provide light to reflect off the paper so you can see it

3. What types of mirror could you sue for make-up or shaving? What would be the advantages of each type?

For shaving you might want to use a concave mirror, and the advantage here is that it will give you a magnified image so you can see If you missed anything, and for make-up you could use a convex mirror, and the advantage of that would be you able to see your whole face.

4. If a driver has one convex and one plane rear-view mirror, how would the images in each appear different?

The image in the plane mirror would appear unaltered, while the image in the convex mirror would appear smaller than normal

5. Why could you not use a concave mirror as a rear-view mirror?

Concave mirrors would show you anything that far off it would be smaller and upside down

6. List as many different uses as you can for plane, convex and concave mirrors

Plane: on dresser – rear-view – full size (one in stores)

Convex: rear-view – make-up – stores

Concave: Shaving – Medical - dental