Cell Structure and function

Question 1

What makes up a cell?

Answer 1

Nucleus, Cytoplasm, Plasma membrane

Question 2

What is the function and structure of the nucleus?

Answer 2

functions:
control centre of the cell - controls protein synthesis
contains DNA - genetic material, blueprint for the activity of all cells
structure:
surrounded by nuclear envelope - nuclear pores allow movement of molecules in and out of the nucleus

Question 3

What is the nuclear envelope?

Answer 3

double layered membrane that separates the nucleus from the rest of the cell

Question 4

Ribosomes role and types

Answer 4

needed for protein synthesis
types: free ribosomes and membrane-bound ribosomes

Question 5

Difference between free ribosomes and membrane-bound ribosomes

Answer 5

free ribosomes are suspended in cytosol (cell solution) and make proteins that mostly function in the cytosol whereas membrane-bound ribosomes are bound to endoplasmic reticulum and creates proteins that mostly function in membrane or outside of the cell

Question 6

What does cytoplasm consist of?

Answer 6

1. Organelles “cellular organs” that are mostly surrounded by a membrane
2. Cytosol - a jelly like fluid
3. Inclusions - chemical substances e.g. pigments, stored nutrients

Question 7

What are the types of cytoplasm organelles?

Answer 7

1. endoplasmic reticulum
2. golgi apparatus
3. lysosomes
4. peroxisomes
5. mitochondria

Question 8

What is the Endoplasmic Reticulum and its types?

Answer 8

the ER is an extensive network of membranes joining the nucleus
two types: rough ER and smooth ER

Question 9

Rough Endoplasmic Reticulum

Answer 9

• is attached to the nucleus
• is covered in rough ribosomes
• makes proteins
• acts as a membrane factory by packaging and transporting proteins to the Golgi Apparatus in transport vesicles

Question 10

Smooth Endoplasmic Reticulum

Answer 10

• has specialised functions in particular cells
  e.g. detoxification (liver and kidneys)
  making steroid-based hormones (testes)
  releasing calcium for muscle contraction (skeletal and cardiac muscle)

Question 11

Golgi Apparatus function

Answer 11

• is a series of curved sacs
• accepts transport vesicles form the ER for further processing like a post office
• proteins are modified, sorted and shipped to their final destination such as outside the cell, to the various membranes, to the organelles

Question 12

Lysosomes and Peroxisomes

Answer 12

Membrane bound vesicles containing enzymes that bud off from the ER or golgi apparatus
Lysosomes - break down organic material inside the cell e.g bacteria
Peroxisomes - degrade toxic molecules inside the cell

Question 13

What are enzymes?

Answer 13

Molecules that speed up chemical reactions without being consumed by the reaction
- catalyst
- made up of proteins

Question 14

What are the 4 main tissue types and where are they?

Answer 14

1. Epithelia (external surface of the body, lining internal surfaces, glands)
2. Connective tissue (Bones, Cartilage, tendons, ligaments, adipose (fat) tissue, blood)
3. Muscle (cardiac muscle - involuntary,
   skeletal muscle - voluntary, smooth muscle - involuntary)
   Muscles are important for stabilizing and controlling our organs and movement.
4. Neural tissue (neurons, glia (neuroglia))
   Important for control and cell communication to your muscles

Question 15

Medial and Lateral
Superior and Inferior
Proximal and distal

Answer 15

Medial - towards midline of the body
Lateral - further from the midline of the body
Superior - towards your head
Inferior - towards the ground
Proximal - closer to the attachment of the limb
Distal - further away to the attachment of the limb

Question 16

Anterior (ventral) and Posterior (dorsal)
Superficial and Deep

Answer 16

Anterior - towards front of the body
Posterior - towards back of the body
Superficial - closer to the skin
Deep - deeper inside the body than the skin

Question 17

Sagittal Plane

Answer 17

Divides body into left and right
The midline is the median/midsagittal plane

Question 18

Frontal (coronal) Plane

Answer 18

Divides body into front and back (anterior and posterior)

Question 19

Transverse (horizontal) plane

Answer 19

Divides the body into superior and inferior (top and bottom)
- A transverse section is often called a cross section

Question 20

Explain the role of ribosomes in the production of proteins

Question 21

Mitochondria

Answer 21

Power plant of the cell
- important for producing energy (ATP)

Carries out aerobic cellular respiration
- nutrients in food converted to CO2 and H2O
- released energy is stored as ATP
basically energy in presence of oxygen - take nutrients from our food and as a result releases waste and water (CO2 and H2O)

Question 22

ATP

Answer 22

Adenosine Triphosphate
- the chemical bond between the last two phosphate groups is broken
- energy is released when terminal phosphate group is removed