Cell Structure and Organsisation Flashcards

1
Q

What is the function of the nucleus?

A

It retains the genetic information (DNA) which codes for protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the nuclear envelope and its function?

A

A double membrane with pores to allow the transport of mRNA and ribosomes out of the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the function of the nucleolus?

A

To synthesise ribosomal RNA (rRNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the function of mitochondria?

A

To release energy in the form of ATP during aerobic respiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The inner membrane of a mitochondrion is folded inwards creating extensions called _______

A

Cristae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the function of cristae in a mitochondrion?

A

Increase the surface area for ATP synthesis to occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the function of ribosomes?

A

Site of protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the function of the rough endoplasmic reticulum?

A

Protein synthesis and transport of proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the function of the smooth endoplasmic reticulum?

A

Synthesis and transport of lipids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the 3 main functions of the Golgi apparatus?

A
  • modifying and packaging proteins into secretory vesicles for secretion from the cell
  • producing glycoprotein
  • forming lysosomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the function of lysosomes?

A
  • release hydrolytic (digestive) enzymes when the cell needs to break down worn out organelles
  • digest material that has been taken into the cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the 4 structural components of the cell membrane?

A
  • PHOSPHOLIPIDS (forming bilayer)
  • PROTEINS
  • CARBOHYDRATES (glycolipids and glycoproteins)
  • CHOLESTEROL (animal cells)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why is it called the fluid mosaic model?

A

FLUID: individual phospholipid molecules can move around relative to one another
MOSAIC: proteins embedded in the bilayer vary in size and are arranged in a random pattern

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Function of phospholipids in cell membrane

A

Form selective bilayer that allows non polar/uncharged molecules through but prevents the passage of polar/charged molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Function of extrinsic proteins in cell membrane

A

Associated with one layer only. May act as receptors for hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Function of intrinsic proteins in cell membrane

A

Act as channels to allow the passage of polar molecules eg glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Function of glycocalyx in cell membrane

A

Act as cell to cell recognition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Function of cholesterol in cell membrane

A

Controls membrane fluidity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the function of centrioles?

A

Animal cell only
During cell division, they migrate to opposite poles of the cell and form the spindle

20
Q

What are plasmodesmata and what is their function?

A

Narrow pores in the cell wall. Fine strands of cytoplasm pass through these connecting one cell to the next, allowing substances to move between them.

21
Q

Why do chloroplasts contain circular DNA?

A

For self replication

22
Q

What is the function of chloroplasts?

A

The site of photosynthesis

23
Q

What is the endosymbiotic theory?

A

Organelles such as chloroplasts and mitochondria were originally free living prokaryotic cells

24
Q

What is a prokaryote?

A

Single celled organisms lacking membrane bound organelles, such as nuclei, with DNA free in the cytoplasm

25
Q

What is a eukaryote?

A

Organism made of cells that have membrane bound organelles with DNA within the nucleus in the form of chromosomes

26
Q

Why is a virus not considered living?

A

They do not have organelles, enzymes, chromosomes or cytoplasm.

27
Q

What is the name of a virus that attacks bacteria?

A

Bacteriophages

28
Q

What is a virus made up of?

A

Nucleic acid, surrounded by a protein coat. Some have DNA while others contain RNA

29
Q

What 4 ways can viruses be transmitted?

A
  • aerosol
  • insect vectors
  • exchange of bodily fluids
  • bites
30
Q

What is the definition of an organism?

A

All the systems of the body working together make an organism, which is a discrete individual

31
Q

What does unicellular mean?

A

Single celled organisms which carry out all life functions within one cell

32
Q

What does multicellular mean?

A

Organisms consisting of many specialised cells which form tissues and organs, which have various structures and roles

33
Q

What is differentiation?

A

The process by which a stem cell becomes specialised into a specific type of cell

34
Q

What is division of labour?

A

The adaptation of different parts of an organism to carry out different functions. The more advanced the organism the greater the division of labour.

35
Q

Define a tissue

A

An aggregation of specialised cells carrying out a specific function

36
Q

What are the 4 primary tissue types in the human body?

A
  • Epithelial tissue
  • Muscle tissue
  • Connective tissue
  • Nerve tissue
37
Q

Name the 4 types of epithelial tissue and give an example of where they are found

A
  • Squamous epithelium (mouth, alveoli)
  • Cuboidal epithelium (kidney tubules, ducts of glands)
  • Columnar epithelium (stomach, intestines)
  • Ciliated columnar epithelium (trachea, oviduct)
38
Q

What are the 3 muscle tissue types?

A
  • Cardiac
  • Skeletal
  • Smooth
39
Q

Define an organ

A

An aggregation of several tissues that carry out a specific function for the whole organism

40
Q

Define an organ system

A

2 or more different organs working together to provide a common function

41
Q

What are the 5 plant tissues?

A
  • Xylem
  • Phloem
  • Palisade mesophyll
  • Spongy mesophyll
  • Upper epidermis
42
Q

What is the function of the xylem?

A

Transport of water and dissolved minerals

43
Q

What is the function of the phloem?

A

Transport of sucrose and amino acids (photosynthates)

44
Q

What is the function of the palisade mesophyll?

A

Photosynthesis

45
Q

What is the function of the spongy mesophyll?

A

Some photosynthesis, it provides air space for diffusion of gases in/out of the leaf

46
Q

What is the function of the upper epidermis?

A

Contains cells that are found on the top surface of a leaf, protected by a waterproof waxy cuticle

47
Q

Define chromatin (found in the nucleus)

A

Coils of DNA bound to histone proteins