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Flashcards in GAMSAT ( High Value Bio Topics) Deck (33)
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1

 

Platelets

  • Thrombocytes (yellow blood cells)
  • very small, irregularly shaped clear cell fragments
    • Cells that do not have a nucleus containing DNA
  • 2-3µm in diameter
  • 5-9 day life span
  • help w/ clotting (through hemostasis) & by releasing threadlike fibres to form clots
  • low platelets (thrombopenia) - excessive bleeding 
  • High platelets - clots (thromosis) can form (thrombocytosis)

2

 

White Blood Cells

  • Leukocytes
  • immune system cells involved in defending the body against infectious disease & foreighn materials
  • 5 types of WBC
    1. Monocyte
    2. Eosinophil
    3. Basophil
    4. Lymphocyte
    5. Neutrophil
  • Produced in bone marrow
  • 3-4 day life span
  • Normal levels: 7000/microlitre of blood (1% of blood)
    • ↑ 7000 = leukocytosis  ↓7000 = leukopenia

3

 

Red Blood Cells

  • Erythrocytes
  • carry oxygen & collect CO2 through the use of hemoglobin
  • life span of 120 days
  • Protect healthy cells along w/ white blood cells

4

 

Heart Structure Info

  1. Left ventricle has thicker, more muscular walls than the right b/c it needs to contract more powerfully to pump blood around the body
  2. ventricles have thicker walls than atria b/c atria only have to push blood to ventricles
  3. the atrioventricular (AV) valves link the atria to the ventricles & stop blood flowing back into the heart after ventricles contract
  4. the semi-lunar (SL) valves link the ventricles to the pulmonary arteries & aorta & stop back flow
  5. the cords attach the atrio-ventricular valves to the ventricles to stop them being forced up into the atria w/ ventricular contraction

5

 

Human Circulatory System

- Diagram & names of blood vessles & arteries

6

 

Heart Structure

Diagram

7

Animal Cells

Mitochondrion (ia)

(description & function)

  • Description - usually oval shaped.
    • They have a double membrane - the inner one is folded to form cristae (crista).
    • Inside is the matrix, which contains enzymes involved in respiration
  • Function - the site of aerobic respiration.
    • They're found in large numbers in cells that are very active & require a lot of energy

8

 

Animal Cells

Microvilli

Description & Function

  • Description - Folds in the plasma membrane
  • Function - They're found on cells involved in processes like absorption,
    • such as epithelial cells in the small intestine.
    • They increase the surface area of the plasma membrane. 

9

 

Animal Cells

Golgi Apparatus

Description & Function

 

 

  • Description - a group of fluid-filled sacs

 

  • Function - It processes & packages new lipids & proteins
    • It also makes lysosomes

10

Animal Cells

Endoplasmic Reticulum (2 types)

Description & Function

  • Description - a system of membranes enclosing a fluid-filled space
    • Rough ER is covered in ribosomers
    • Smooth ER is not

 

  • Function
    • Smooth ER - synthesises & processes lipids
    • Rough ER - folds & processes proteins that have been made by ribosomes

11

Animal Cells

Ribosome

Description & Function

  • Description - a very small organelle that floats free in the cytoplasm or is attached to the rough endoplasmic reticulum

 

  • Function - The site where proteins are made

12

Animal Cell

Lysosome

Description & Function

  • Description - a rough organelle surrounded by a membrane w/ no clear internal structure

 

  • Function - contains digestive enzymes
    • These are kept separate from the cytoplasm by the surrounding membrane and can be used to digest invading cells or to break down worn out components of the cell

13

Animal Cell

Nucleus

Description & Function

  •  Description - a large organelle surrounded by a nuclear envelop (double membrane) which contains many pores
    • the nucleus contains chromatin & often a structure called the nucleolus

 

  • Function - Chromatin is made from proteins & DNA
    • The pores allow substances (RNA) to move between the nucleus & the cytoplasm
    • The nucleolus makes ribosomes

14

Animal Cells

Plasma Membrane

Description & Function

  • Description - membrace found on the surface of animal cells (and just inside the cell wall of plant cells)
    • made mainly of lipids & protein

 

  • Function - regulates the movement of substances into & out of the cell
    • it also has receptor molecules on it which allow it to respond to chemicals like hormones

15

Animal Cell 

  1. Plasma Membrane
  2. Rough Endoplasmic Reticulum (ER)
  3. Golgi Aparatus
  4. Cytoplasm
  5. Mitochondria
  6. Nucleus
  7. Nuclear Envelope
  8. Smooth Endoplasmic Reticulum
  9. Lysosome
  10. Ribosome

16

 

Cellular Transport

Active Transport

  • Moves substances against concentration gradients
    • Low concentration to high
  • Uses energy to move molecules & ions across membranes
  • Carrier proteins & co-transporters are used

17

Cellular Transport

Carrier proteins in Active transport

  • Process is the same as in facillitated diffussion
    • molecule attaches to protein, changes shape, moves across membrane, releases it
    • except that energy is used (from ATP) to move the solute against its concentration gradient

 

18

Cellular Transport

Co-transporters in active Transport

  • a type of carrier protein
  • they bind 2 molecules at one time
  • the concentration gradient of one of the molecules is used to move the other against its own concentration gradient

 

 

19

Cellular Transport

Facilitated Diffusion

  • some larger molecules (amino acids, glucose) & gharged atoms (chloride ions) can't diffuse directly through the phospholipid bilayer of the cell membrane
  • instead they diffuse through carrier proteins or protein channels in the cell membrane
  • they move down a concentration gradient so it is a passive process (no energy)

20

Cellular Transport

Carrier Proteins

  • move larger molecules in to or out of the cell down their concentration gradient
  • different carrier proteins facilitate the diffustion of different molecules
    1. large molecule attaches to a carrier protein in the membrane
    2. the protein changes shape
    3. releases the molecule on the opposite side of the membrane

21

Cellular Transport

Protein Channels

  • Form pores in the membrane for charged particles to diffuse through (down concentration gradient)
  • Different protein channels facilitate the fiddusion of different charged particles

22

Cellular Transport

Diffusion

  • The passive movement of Particles (no energy needed)
  • The net movement of particles (molecules or ions) from an area of higher concentration to one of lower concentration
    • They move both ways but net is from high to low until they are evenly distributed through out gas or liquid
  • Concentration Gradient - the path from higher to lower concentration. 
    • Particles move down the gradient
  • Particles can diffuse across the plasma membranes as long as they can move freely through the membrane

23

Cellular Transport

Rate of Diffusion

Depends on several Factors

  1. Concentration gradient - higher it is the faster the rate of diffusion
  2. Thickness of the sexhange surface - the thinner the surface the faster the rate
  3. Surface area - larger the surface area of the plasma membrane the faster the rate

*microvilli can increase the surface area by about 600 times*

24

Cellular Transport

Osmosis

  • The diffusion of water molecules across a partially permeable membrane (higher water potential to a lower one)
  • Plasm membranes are partially permeable & allow some small particles (like water) to pass through but not large solute molecules
  • Pure water has the highest water potential
    • all solutions have a lower water potential than pure water
  • 2 solutions w/ equal water potential are ISOTONIC

25

Cellular Transport

Water Potential

  • The likelihood of water molecules to diffuse out of/or into a solution

 

  • Pure water has the highest water potential

26

 

Meiosis

Cell division where diploid cells split into 4 halves

*Useful to have correct number of chromosomes when gametes fuse

  1. DNA unravels & replicates so there are 2 copies of each chromosomes called chromatids
  2. The DNA condenses to form double-armed chromosomes, made from, two sister chromatids
  3. Meiosis I (first division) - the chromosomes arrange themselves into homologous pairs
  4. These homologous pairs are then separated having the chromosome #
  5. Meiosis II (2nd division) - the pairs of sister chromatids that make up each chromosome are separated
  6. 4 haploid cells (gametes) that are genetically different from each other are produced
    • Chromatid cross over in Meiosis I

- homologous pairs of chromosomes come together & pair up. The chromatids twist around each other & bits of chromatids swap over

- Same # of genes but different combination of alleles

 

27

Mitosis

Info & Stages

  • In mitosis a parent cell divides to produce 2 genetically identical daughter cells containing an exact copy of the DNA of the parent cell
  • One continous process but described in 4 stages of division (with Interphase happening before mitosis)
  • Interphase
  1. Prophase
  2. Metaphase
  3. Anaphase
  4. Telophase

28

Mitosis

Interphase

- Technically before mitosis begins

  • The Cell carries out normal functions but also prepares to divide
    • the cells DNA is unravelled & replicated, to double its genetic content
    • The organelles are also replicated so it has spare ones & ATP content is increased (ATP provides the energy needed for cellular division)
    •  

29

Mitosis

Prophase

IPMAT - First stage of Mitosis (Interphase doesn't count)

  • The Chromosomes condense (shorter & fatter)
  • Tiny bundles of protein called centrioles start moving toward opposite ends of the cells, forming a network of protein fibres across the cell called the spindle
  • The nuclear envelope breaks down leaving the chromosomes free in cytoplasm

 

30

Mitosis

Metaphase

  • 2nd stage mitosis (IPMAT)
  • the chromosomes (2 chromatids each) line up along the middle of the cell & become attached to the spindle by their centromere
  •