Unit 2 final review

Question 1

Who was Anton van Leeuwenhoek?

Answer 1

Van Leeuwenhoek discovered the single-celled organisms and he called them “animalcules”.

Question 2

Who was Robert Hooke?

Answer 2

Robert Hooke used an improved compound microscope he had built to study the bark of a cork tree. In doing so he discovered and named the cell the building block of life

Question 3

two main hypotheses that was the basis of the “cell theory”?

Answer 3

1. All living things are composed of one or more cells.

2. Cells are the basic units of structure and function in all organisms.

Question 4

What is the Compound Light Microscope and what does it do?

Answer 4

Compound light microscopes have two lenses, which give greater power of magnification.

Question 5

Parts of a microscope

Answer 5

the eyepiece, tube, coarse adjustment knob, fine adjustment knob, arm, revolving nose piece, objective lens, stage, the condenser lens, the diaphragm, and the light source.

Question 6

What is the cell membrane?

Answer 6

It surrounds and protects the contents of the cell.

Question 7

What is the nucleus?

Answer 7

It controls the cell’s activities. It contains the chromosomes structures made of genetic material that directs a cell’s growth and reproduction.

Question 8

why do cells not grow very large?

Answer 8

A cell doesn’t grow too large because they need a constant supply of materials in order to stay alive.

Question 9

What does permeable mean?

Answer 9

a type of cell membrane that allows all substances to pass through.

Question 10

What is a tissue?

Answer 10

A group of cells that act together to perform a specific function.

Question 11

circulatory system

Answer 11

The body system made up of the heart, blood, and blood vessels. This system moves materials to and from the body cells.

Question 12

Respiratory system

Answer 12

The body system made up of the larynx, trachea, alveoles, bronchus, bronchioles, the lungs, and the diaphragm. The respiratory system brings oxygen to the body’s cells and removes wastes.

Question 13

What are villi?

Answer 13

Villi cover the surface of the small intestine and absorb the digested food.

Question 14

In millimetres what is the smallest object a human eye can see?

Answer 14

the human eye can see objects as small as 0.1 millimetres.

Question 15

Explain the difference between multicellular and unicellular organisms?

Answer 15

A multicellular cell is made up of many cells and the unicellular cell is only made up of one cell.

Question 16

What are the chloroplasts?

Answer 16

the structures inside the plant cell in which the process of photosynthesis takes place

Question 17

What does selectively permeable mean?

Answer 17

selectively permeable allows certain substances through while others cannot

Question 18

Diffusion definition

Answer 18

Movement of molecules from an area of higher concentration to an area of lower concentration.

Question 19

Osmosis definition

Answer 19

The diffusion of water (which usually has nutrients for the cell) spreads through a selectively permeable membrane.

Question 20

What is an organ?

Answer 20

A group of different tissues that work together to perform a certain function.

Question 21

What are systems?

Answer 21

a group of organs working together to perform a complex body function.

Question 22

Which structures connect the arteries and veins?

Answer 22

Capillaries connect to the arteries and veins

Question 23

transmission electron microscope

Answer 23

A microscope that uses an electron beam to study the internal structure of thinly sectioned specimens.

Question 24

What is the cell wall?

Answer 24

surrounds the cell membrane of the plant cell; provides support and shape.

Question 25

digestive system

Answer 25

Breaks down food into absorbable units that enter the blood for distribution to body cells. It is made of the

Question 26

What happens when you breathe out?

Answer 26

Breathing out (exhalation) get rid of the body’s wastes like carbon dioxide.

Question 27

Which vessels transport blood away from the heart and have a thick muscular wall?

Answer 27

The arteries transport blood away from the heart.

Question 28

What is the Scanning Electron Microscope and what does it do?

Answer 28

use beams of electrons instead of light. The electrons are bounced off the sample, then enlarged to form an image on a television screen or photographic plate.

Question 29

Explain why unicellular organisms are not simple?

Answer 29

Each has a way of moving, obtaining food, and carrying out all other functions essential for life.

Question 30

What is the cytoplasm?

Answer 30

it distributes materials such as oxygen (blood for the cells).

Question 31

What are vacuoles?

Answer 31

Storage places for the cells food, wastes and other substances that the cell does not need right away.

Question 32

Explain the differences between a plant and an animal cell.

Answer 32

1. The plant cell is more complex than an animal cell

2. The animal cell has a less thick cell membrane

Question 33

What does impermeable mean?

Answer 33

A type of cell membrane that does not allow any substances through.

Question 34

What happens when you breathe in?

Answer 34

Breathing in (inhalation) fills our lungs with oxygen-containing air.

Question 35

Which vessels transport blood toward the heart and have valves?

Answer 35

the veins transport blood toward the heart.

Question 36

Why is the circulatory system important to humans?

Answer 36

The circulatory system carries oxygen, nutrients, and hormones to cells, and removes waste products, like carbon dioxide.