Chapter 2 - Organisation Of The Organism

Question 1

What is the difference between eukaryotes and prokaryotes and where are they found?

Answer 1

Eukaryotes are found in plants and animals and they are typically larger and contain nucleus, Ribosomes and mitochondria

Prokaryotes are found as bacteria cells and do not contain a nucleus, Ribosomes and mitochondria, They also do not contain a rough endoplasmic reticulum.

Question 2

How do you calculate the actual size of a specimen under a microscope?

Answer 2

image size/magnification

Question 3

Functions of eukaryotic cell structures and also additional ones in plant cells eg nucleus

Answer 3

Cell membrane - surrounds cell and controls entry and exit of substances

Cytoplasm - Jelly like substance in which reactions occur, contains structures such as Ribosomes and vesicles

Ribosomes - Site of protein synthesis

Rough endoplasmic reticulum - Surrounds nucleus and has Ribosomes attached

Mitochondria - Respiration takes place here for energy

Vesicles- used to transport materials in the cell

Nucleus and DNA - Contains genetic material in format of DNA for proteins

Vacuole - fluid filled sac containing mineral salts, sugars, amino acids, waste substances and pigment which color cell

Chloroplasts - site of photosynthesis

Cell wall - gives cell structure and stops it from bursting also controls entry and exit of substances.

Question 4

What are specialized cells?

Answer 4

Cells and tissues specialized to carry out a particular function

Question 5

Give some examples of specialized cells and what they do.

Answer 5

Ciliated cells - found lining trachea and have hair like projections called silia which move together to transport mucus, dust and bacteria upwards

Root hair cells - Have a large surface area

Xylem vessels - Used to transport water through plants. Made from dead hollowed cells with ends removed to make a tube, have a thick cell wall to give struture

Palisade mesophyl cells - Where photosynthesis occurs, tall and are closely packed and contain lots of chloroplasts, placed at top of leaf

Nerve cells - Nerve cells are adapted to rapidly transmit electrical impulses, myelinated to insulate to stop impulse weakening, contain lots of mitochondria,

Red blood cells - Contain hemoglobin which allows them to carry oxygen and have a special shape to allow rapid diffusion, no nucleus

Sperm cells - Have lots of mitochondria and a tail to move and Enzymes to penetrate egg cell

Question 6

Define tissue, organ, organ system and organelles?

Answer 6

Tissue - a group of cells with similar structure working together to perform a specific function

Organ - a structure made of tissues working together to carry out special functions

Organ system - A group of organs with related functions working together to perform body functions

Organelles - a structure within a cell