Cells

Question 1

What are the main features of all Animal Cell

Answer 1

They are multicellular
Their cells contain a nucleus with a distinct membrane
Their cells do not have cellulose cell walls
Their cells do not contain chloroplasts (so they are unable to carry out photosynthesis)
They feed on organic substances made by other living things
They often store carbohydrates as glycogen
They usually have nervous coordination
They are able to move from place to place

Question 2

What are the main Features of Plant Cell

Answer 2

They are multicellular
Their cells contain a nucleus with a distinct membrane
Their cells have cell walls made out of cellulose
Their cells contain chloroplasts (so they can carry out photosynthesis)
They feed by photosynthesis
They store carbohydrates as starch or sucrose
They do not have nervous coordination

Question 3

Define Nucleus

Answer 3

Contains the Genetic Material (DNA) which controls the activities of Cell

Question 4

Define Cytoplasm

Answer 4

A Gel like substance composed of water and dissolved solutes supports the internal structure of Cell
Site of many chemical reactions including Anearobic Respiration

Question 5

Define Cell Membrane

Answer 5

Holds the Cell together seperating the inside of the cell from the outside
Controls which substances can enter and leave the cell

Question 6

Define Ribosomes

Answer 6

Found in the cytoplasm site of the protein synthesis

Question 7

Define Mithochondrion

Answer 7

Site of most reactions involved in Aerobic Respiration where energy is released to fuel cellular processes
Cells with High Rates of metabolism (carrying out many different cell reactions) have significantly higher numbers of mithochondria than cells with fewer reactions taking place.

Question 8

Define Cell Wall

Answer 8

Made of Cellulose ( A polymer of glucose )
Gives the cell extra support, defining its shape

Question 9

Define Chloroplast

Answer 9

Contains a green chlorophyll pigments (to absorb light energy) and the enzymes needed for photosynthesis

Question 10

Explain the structure of Bacteria Cells

Answer 10

They are microscopic single-celled organisms
Possess a cell wall (made of peptidoglycan, not cellulose), cell membrane, cytoplasm and ribosomes
Lack a nucleus but contain a circular chromosome of DNA that floats in the cytoplasm
Plasmids are sometimes present - these are small rings of DNA (also floating in the cytoplasm) that contain extra genes to those found in the chromosomal DNA
They lack mitochondria, chloroplasts and other membrane-bound organelles found in animal and plant cells

Examples of bacteria include:
Lactobacillus (a rod-shaped bacterium used in the production of yoghurt from milk)
Pneumococcus (a spherical bacterium that acts as the pathogen causing pneumonia)

Question 11

Define Specialised Cell

Answer 11

pecialised cells are those which have developed certain characteristics in order to perform particular functions. These differences are controlled by genes in the nucleus

Question 12

What are the functions and Adaptations of Ciliated Cell

Answer 12

Functions: Movement of Mucus in the trachea and Bronchi
Adaptations: Extensions of the cytoplasm at the surface of the cell form hair like structures called Cilia which beat to move the mucus and trapped particles upto the throat

Question 13

What are the functions and Adaptations of Nerve Cell

Answer 13

Fuctions: Conduction of impulses
Adaptations: Long so that the nerves can run to and from the different parts of the body in central nervous system
The cells have extensions and branches so it can communicate with with other nerve cells, Muscles and glands
The axon ( extension of cytoplasm away from the cell body) is covered with a fatty sheath, which insulates the nerve cell and speeds up the nerve impulses