Life at the Cellular Level Flashcards Preview

Science for Med Revision > Life at the Cellular Level > Flashcards

Flashcards in Life at the Cellular Level Deck (27):
1

Difference between passive and facilitated transport?

- Both require conc. gradients
- Facilitated needs carrier molecules

2

Define endocytosis

Invagination of the cell membrane to take in extracellular materials

3

Define exocytosis

- Vesicle produced
- Internally made proteins put inside vesicle
- Vesicle fuses with cell membrane and constituents move out

4

Role of an occluding/tight junction

- Waterproof
- Seals gap in-between cells
- Stops absorbed nutrients from returning in-between the cells

5

Role of adherens junction?

- Uses actin
- Connects two cells to each other to allow uniform movement

6

Role of desmosomes

- Uses intermediate filaments
- Connects two cells to each other to allow uniform movement and structure

7

Which of the two adhering junctions is stronger?

Desmosomes

8

Role of gap junctions

Allow communication between cells

9

What messenger molecules move through gap junctions

Small, water soluble

10

What is the name of the protein that makes the pores of the mitochondria?

Porin

11

What shape is mitochondrial DNA found?

Circular

12

3 things found in the nucleus?

- DNA
- Nucleoproteins
- RNA

13

Where is rRNA synthesised?

Nucleolus

14

Role of the rough ER?

- Protein modification and transport

15

Role of the golgi apparatus?

- Protein modification and packaging of complete polypeptides into vesicles
- Can synthesise complex polysaccharides

16

What is the role of the smooth ER?

Breaks down
- Drugs
- Glycogen
Synthesises
- Lipids

17

Role of lysosomes?

- Contain digestive enzymes so they don't digest the cell

18

Main functions of the cytoskeleton?

- Structure
- Motility
- Organisation of organelles
- Involved in cytoplasmic streaming

19

3 parts of the cytoskeleton?

- Actin
- Intermediate filaments
- Microtubules

20

What are intermediate filaments made of?

- Fibrous proteins

21

What are microtubules made of?

Tubulin

22

Name the 10 most common elements found in the body

- H
- O
- C
- N
- Ca
- Na
- Cl
- P
- S
- K

23

What do S groups allow to form

Disulphide bridges

24

What is configuration?

The FIXED arrangement of atoms in a molecule, either cis of trans

25

What are the 5 reactions that occur in the body?

- Breaking and forming C-C bonds
- REDOX
- Internal rearrangements
- Group transfers
- Condensation/hydrolysis

26

What is conformation?

- The PRECISE arrangement of atoms in a molecule with FREE ROTATION

27

What is the role of the peroxisome?

- Break down of FA's with chains longer than 22 C's
- Breaking down hydrogen peroxide