Cells

Question 1

Define cells :

Answer 1

The smallest unit from all organism are made

Question 2

What are cells ?

Answer 2

Cells are what makes living organism . Cells are made when a fully grown cell divides . To see cells you need a microscope.

Question 3

What is an electron microscope?

Answer 3

An electron microscope is a type of microscope that uses a beam of electrons instead of light and can magnify 500,000 times . It can be used to see more detail in a cell

Question 4

Define electron micrograph :

Answer 4

An image made using an electron microscope

Question 5

Define cell membrane :

Answer 5

A very thin layer surrounding the cytoplasm of every cell ;it controls what enters and leaves the cell

Question 6

Define partially permeable:

Answer 6

Allows some molecules and ions to pass through it

Question 7

Define cell wall :

Answer 7

A tough layer outside the cell membrane ;found in the cell of plants ,fungi and bacteria

Question 8

Define fully permeable :

Answer 8

Allows all molecules and ions to pass through

Question 9

Define cytoplasm :

Answer 9

The jelly-like material that fills a cell

Question 10

Define metabolic reactions :

Answer 10

Chemical reactions that take place in living organisms

Question 11

Define vacuole :

Answer 11

A fluid-filled space inside a cell,seperate from the cytoplasm by cell membrane

Question 12

Define cell sap :

Answer 12

The fluid that fills the large vacuole in plant cell

Question 13

Define Vesicles :

Answer 13

A very small vacuole

Question 14

Define nucleus :

Answer 14

A structure containing DNA in the form of chromosomes

Question 15

Define Chromosomes:

Answer 15

A length of DNA found in the nucleus of a cell ;it contains genetic information in the form of many different genes

Question 16

Define DNA :

Answer 16

A molecule that contains genetic information,in the form of genes that controls the protein that are made in the cell

Question 17

Define chloroplast :

Answer 17

Small structures found inside some plant cells inside which photosynthesis takes place

Question 18

Define starch grains :

Answer 18

Tiny places of starch made of thousand of starch molecules that are stored in some plant cells

Question 19

Define mitochondria:

Answer 19

A small structure in the cell where aerobic respiration releases energy from glucose

Question 20

Define aerobic respiration :

Answer 20

Chemical reaction that takes place in mitochondria which uses oxygen to break down glucose and other nutrient molecules to release energy for the cell to use

Question 21

Define ribosome :

Answer 21

Very small structures in a cell that uses information on DNA to make protein molecules

Question 22

What is cell membrane ? What is its function ?

Answer 22

A cell membrane is a thin layer of protein and fat . Its function is to control what enters and exits the cell . It’s partially permeable . It lets some substances in but not all out. It separates the content of the cell from the outside . Found in plant,animal,bacteria cells

Question 23

What is the cell wall ? What is its function ?

Answer 23

The cell wall is a tough layer on the outside or the cell . In plant cell it is made from cellulose . Its function is to provide structure and support the cell . Cellulose forms strong cross-cross fibres that protect the cell . The cell wall also stops the cell from bursting if it absorbs a lot of water . It is fully permeable as it allows all molecules to pass through . It is found only in plant cells

Question 24

What is the cytoplasm ? What is its function ?

Answer 24

The cytoplasm is a jelly-like substance . 70% of it is water in many cells and many substances dissolve in it especially protein . Its function is to support the many metabolic reactions that take place in the cytoplasm while also providing structure and support to the cell. Found in plant,animal, bacteria cells

Question 25

What is the vacuole ? What is its function ?

Answer 25

The vacuole is a fluid-filled space inside a cell surrounding by a membrane . Plant cells have large vacuole which contain sugars , other solutions and cell sap . When full it presses out on the cells. Animal cells have vesicles , smaller vacuoles which contain water and nutrients . Its function is to store nutrients for further use . Found in plant,animal,bacteria cell .

Question 26

What is the nucleus ? What is its function ?

Answer 26

The nucleus is where genetic information is stored . The information is stored on chromosomes which are inherited from the organism’s parents . The chromosomes are made of DNA which determines what kind of proteins are made in the cell . Its fiction is to control the cells activity . Found in most cells .

Question 27

What is the Ribosome ? What is its function ?

Answer 27

Ribosome are tiny structures that can only be seen by an electron microscope. Its function is to make protein and help with protein synthesis. The DNA instructions links amino acids in a particular sequence. It’s found in plant,animal,bacteria cells .

Question 28

What are chloroplast ? What is its function ?

Answer 28

Chloroplast are small organelles that help plants perform photosynthesis. They contain a green pigment called chlorophyll which gives plants its colour. Its function is to absorb energy for the plant by photosynthesis. Chloroplast contain starch grains which are made by photosynthesis. Chloroplast are only found in plant cells

Question 29

What is mitochondria? What is its function ?

Answer 29

Mitochondria are the part of the cell where aerobic respiration happens . It can only be seen by an electron microscope. Its function is to provide respiration for the cell . Aerobic respiration is the main way cells get energy to stay alive . More energy a cell needs the more mitochondria the cell has . It is found in plants,animal cells .

Question 30

Define Bacteria :

Answer 30

Unicellular organism whose cells do not contain a nucleus

Question 31

Define prokaryotic cells :

Answer 31

Cells with no nucleus ;bacteria have prokaryotic cells

Question 32

Define plasmid :

Answer 32

Small circular molecules of DNA found in many prokaryotic cells in addition to the main much larger circle of DNA

Question 33

How does bacteria cells differ from plant and animal cells al cells ?

Answer 33

Bacteria have a cell wall but it it not made of cellulose . The function is the same to support the cell and stop it from bursting if it takes too much water . The cell membrane is present however is pushed tightly against the cell wall. The cytoplasm and ribosome is present and is the same . Bacteria does not have chloroplast or mitochondria.

Question 34

What is the most importantly difference between?

Answer 34

The most important difference is that bacteria cells do not have a nucleus . Bacteria cells are known as prokaryotic “pro “meaning before “karyotic” meaning nucleus. Prokaryotic cells appeared millions of years before cells with nuclei on earth .

Question 35

What does DNA in bacteria cells do ?

Answer 35

Instead of chromosomes in a nucleus . Bacteria have a circle of DNA called bacteria chromosomes. It provides instructions for making proteins .

Question 36

What are plasmids ? What are they used for ?

Answer 36

Bacterial cells have one or more smaller circles called plasmids. They are used for genetic modification of cells by scientists

Question 37

How do bacteria cells reproduce ?

Answer 37

Through the process of Binory fission . They elongate and the plasmid duplicates resulting in the clowning of the cell

Question 38

Define tissue :

Answer 38

A group or similar cells that work together to form a particular function

Question 39

Define organ :

Answer 39

A group of tissues that work together to perform a particular function

Question 40

Define organ system :

Answer 40

Several organs that work together to perform a particular function

Question 41

Define magnification :

Answer 41

How many times larger an image is than the actual object

Question 42

What are tissues ?

Answer 42

Cells that specialise in the same activity . An example of a group of cells is the layer of cells that line your stomach

Question 43

What are organs ?

Answer 43

A group or different tissues that work together is called an organ . For example your heart,kidney

Question 44

What are organ system ?

Answer 44

Several organs that work together is called an organ system. For example the heart is part of the circulatory system and the kidney is part of the endocrine system.

Question 45

What makes up an organism :

Answer 45

Organism -> Organ system -> organs -> tissues -> cells

Question 46

What is the formula for magnification ?

Answer 46

Size of image / size or actual object

Question 47

What are the two rules of magnification?

Answer 47

1. Always keep numbers in your calculations in the same unit . Good idea to convert the answer so all units are the same 2. Always write your answers with X in front ,magnification does not have a unit .