Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > cell structure > Flashcards

cell structure Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What is a eukaryotic cell?

A
  • contains membrane enclosed organelles
  • have DNA in the firm of chromosomes in the nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is in the nucleus

A
  • nuclear envelope
  • nuclear pores
  • chromatin
  • nucleolus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the role of the nucleus

A
  • largest organelle
  • contains DNA, and genetic material
  • instructions for cellular processes
  • has hereditary information
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the nuclear envelope?

A
  • double membrane
  • protects the content of nucleus from damage in the cytoplasm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the nuclear pores?

A
  • allows substances to enter and leave the cell
  • mainly allows RNA out bc DNA is too big as well as enzymes and ribosomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are chromatin?

A
  • DNA wrapped around histones (proteins) which then condense to make chromosomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the nucleolus

A
  • area in Nucleus responsible for making ribosomes
  • composed of proteins and RNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the endoplasmic reticulum

A
  • made of a network of flattened sacs called cisternae
  • makes proteins, calcium storage, lipid metabolism, synthesis of carbs and lipids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the rough ER

A
  • main site of protein synthesis
  • lined with ribosomes => cause its roughness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the smooth ER

A
  • responsible for synthesis of carbohydrates and lipids
  • detoxification of drugs and toxins
  • synthesises lipids such as cholesterol and phospholipids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the mitochondria

A
  • the site of aerobic respiration and produces ATP
  • has a double membrane and contains own DNA
  • Inner membrane folds to form cristae => increases SA => more resp
  • releases energy
  • contains DNA and ribosomes for replication
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is ATP?

A

adenosine triphosphate

  • stores and releases energy for cellular processes through cellular respiration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the cell membrane made of?

A
  • also known as the plasma membrane
  • made of lipids and proteins and is formed by phospholipid belayer
  • it is partially permeable and controls what enters and leaves the cell
  • role in cell signalling = cells detect signals from other cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the golgi apparatus?

A
  • made of cisternae (flattened membranous sacs)
  • modifies and processes and packages proteins to be transported
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are Golgi vesicles

A
  • small membrane bound sacs, bud off Golgi apparatus
  • transport proteins and lipids to places within the cell or to cell membrane to be secreted
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are lysosomes?

A
  • specialised vesicles that contain enzymes (digestive and hydrolytic)
  • break down waste products
  • used in phagocytosis

-small organelles filled with enzymes

17
Q

What is the cytoskeleton?

A

a network of fibres extending throughout the cytoplasm

  • control cell structure and movement
18
Q

What does the cytoskeleton consist of?

A

microtubules, microfilaments, intermediate filaments, centrioles

19
Q

What are microfilaments?

A
  • threadlike structures/fibres made up of a protein called actin
  • contractile fibres needed for cytokinesis and cell movement
20
Q

What are microtubules

A

hollow structures made up of the protein tubulin, they maintain a cells shape

  • act as scaffolding
  • dictate shape
  • transport system for movement of vesicles and organelles
21
Q

what are intermediate fibres

A
  • fibres give mechanical strength to cells
  • help maintain their integrity.
22
Q

What are centrioles?

A
  • help organize cell division
  • formed from tubulin and located near the nucleus.
  • made of microtubules
  • two form centrosome = needed for organising spindles in cell division
  • in eukaryotic cells apart from flowering plants and fungi
23
Q

What is in a plant cell?

A
  • nucleus and its contents
  • Rough and Smooth ER
  • cell wall
  • cell membrane
  • vacuole
  • chloroplast
  • Golgi apparatus and vesicles
  • ribosomes
  • mitochondria
24
Q

What are chloroplasts?

A
  • have a double membrane
  • site of photosynthesis
  • contains chlorophyll in thylakoid = trap light
  • inner fluid is stroma
  • fluid filled membrane sacs are thylakoids
  • sacs stack on top of each other to form granum
  • photosynthesis takes place in grana and stroma
  • contains own DNA and ribosomes
25
Q

What is the vacuole?

A
  • membrane bound sac
  • membrane is called tonoplast = allows certain substances/molecules in
  • contributes to growth

— detoxification

  • cellular homeostasis
26
Q

describe the structure of mitochondria

A

Two phospholipid membranes:
- outer: smooth + permeable to small molecules
- inner: folded, site of electron transport chain, location of ATP synthase

Intermembrane space:
- low pH = high conc of protons
- conc gradient across inner membrane formed during oxidative phosphorylation

Matrix
- aqueous solution within the inner membranes
- Contains ribosomes, enzymes and circular mitochondrial DNA necessary for function

27
Q

what is division of labour?

A
  • when diff individuals/cells/tissues become specialised to perform complementary tasks that benefit the whole organism
  • describes specialised functions of cell organelles which come together to ensure cell is capable of surviving as well as performing role in body
28
Q

what endosymbiosis?

A
  • where one organism lives within another.
  • If the relationship is beneficial to both organisms the engulfed organism is not digested
  • to occur one organism must have engulfed the other by the process of endocytosis.
29
Q

what is endosymbiosis in relation to organelles?

A
  • theory that mitochondria, chloroplasts and other eukaryotic organelles were once free living prokaryotic bacteria
  • they were taken into the cell = endosymbiont = organism living inside another
  • lead to evolution of eukaryotic cells
  • larger anaerobically respiring prokaryote engulfed a smaller aerobically respiring prokaryote (not digested)
  • larger prokaryote has a competitive advantage = ready supply of ATP
  • gradually the cell evolved into the heterotrophic eukaryotes with mitochondria that are present today
  • during evolution, the heterotrophic eukaryotic cell engulfed a smaller photosynthetic prokaryote.
  • cell provided a competitive advantage as it supplied the heterotopic cell with an alternative source of energy, carbohydrates
  • Over time the photosynthetic prokaryote evolved into chloroplasts and the heterotrophic cells into autotrophic eukaryotic cells
30
Q

what is the evidence for endosymbiotic theory?

A
  • mitochondria and chloroplasts have similar size to other prokaryotic cells
  • they have double membranes
  • contains own circular non membrane bound DNA
  • both transcribe mRNA from their DNA

(bacteria and mitochondria + chloroplasts)

31
Q

what is the relationship between organelles in protein synthesis?

A
  • mRNA binds to ribosomes in rough ER and protein chains are made
  • can travel through cisternae - packaged into transport vesicles on cytosketeton
  • transported to cis-face of golgi body to be modified/packed in golgi vesicles
  • transported to trans face of glogi apparatus
  • secretory vesicles fuse with cell membrane to release proteins from cells - exocytosis
32
Q

what are the features of the cytoskeleton?

A

microtubules
microfilaments
centrioles
intermediate fibres

33
Q

what are the microtubules?

A
  • 25 nm in diameter
  • acts as scaffolding in cell to support cell shape
  • acts as tracts for organelle and vesicle movement using ATP
  • globular proteins to form tubes, formed from tublins
    - α and β tubulin combined to form
    dimers, the dimers are then joined into
    protofilaments
    - Thirteen protofilaments in a cylinder
    make a microtubule
  • make spindle fibres
  • make shape of cytoplasm
  • tiny cylinders
  • can attach to organelles and change length to cause movement
34
Q

what are the microfilaments?

A
  • used for cell movement + contraction in cytokinesis
  • made from contractile protein = actin
35
Q

what are intermediate fibres?

A
  • more permanent
  • mechanical strength and integrity
  • play role in cell structure
  • anchor organelles in place
36
Q

what would be a problem of defective cytoskeleton?

A

cells wont be able to move

Biology (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions