Biology - Animal Cells, Tissues, Cancer

Question 1

Differences Between Animal and Plant Cells

Answer 1

Plant cells have cell walls, chloroplasts, and one large vacuole. Animal cells have centrioles and multiple small vacuoles.

Question 2

Cell Cycle

Answer 2

Interphase, Prophase, Metaphase, Anaphase, Telophase, Cytokinesis

Question 3

Interphase

Answer 3

90% of cell cycle
Growth 1: cell grows larger until surface area to volume ratio is unhealthy
Synthesis: DNA duplication
Growth 2: organelles needed for cell division are grown

Question 4

Prophase

Answer 4

DNA forms chromosomes (two chromatids joined at a centromere), nuclear membrane breaks down, centrioles move to opposite poles, spindle fibres begin to grow

Question 5

Metaphase

Answer 5

Chromosomes line up at middle, spindle fibres attach to centromeres

Question 6

Anaphase

Answer 6

Spindle fibres break apart chromatids and pull to opposite poles, forming daughter chromosomes

Question 7

Telophase

Answer 7

Daughter chromosomes become long and thin again (invisible), nuclear membranes begin to reappear, spindle fibres disappear

Question 8

Cytokinesis

Answer 8

Cytoplasm and all organelles divide between daughter cells, cell furrow/cell plate forms

Question 9

Apoptosis

Answer 9

Natural cell death
Different types of cells have different cell cycle lengths (skin cells: 14-28 days, red blood cells: 120 days)

Question 10

Why is cell division necessary?

Answer 10

Growth, Reproduction, Repair

Question 11

Cell Differentiation

Answer 11

The process of creating specialized cells:
- All cells start from zygote undergoing mitosis which forms blastocyte
- As embryo develops, cells change shape, form, and functions
- Daughter cells have the same DNA, but different genes may be turned on and off

Question 12

Factors Causing Specialization

Answer 12

1. Cytoplasm Differences: asymmetrical distribution of organelles and other factors in zygote
2. Environmental Conditions: variations in temperature and nutrients
3. Neighbouring Cells: substances can diffuse from nearby cells

Question 13

Abnormal Development

Answer 13

Cellular development impacted from chemical contamination of environment

Question 14

Stem Cells

Answer 14

Cells that can differentiate into different cell types

Question 15

Types of Stem Cells

Answer 15

1. Embryonic Stem Cells: from 5-7 day old embryos –> can differentiate into any cell type
2. Adult Stem Cells: exists in some tissues –> can only differentiate into specific cell types
3. Induced Pluripotent Stem Cells (iPSC): virus is injected into adult cells to insert additional genes –> can differentiate into any cell type

Question 16

Heirarchy of Structure in Animals

Answer 16

Specialized Cells –> Tissue –> Organs –> Organ Systems –> Organisms

Question 17

Tissue

Answer 17

Collection of similar cells that preform a specific function

Question 18

Epithelial Tissue

Answer 18

Lines the inner and outer surfaces of the body; forms a barrier by connecting cell membranes

Question 19

Muscular Tissue

Answer 19

Moves the body or organs by contracting and relaxing

Question 20

Connective Tissue

Answer 20

Strengthens, supports, and protects other tissues (cells are in extracellular matrix)

Question 21

Nervous Tissue

Answer 21

Made up of neurons with long projections that send and receive signals - coordinates body actions

Question 22

Cancer

Answer 22

The uncontrolled division and spread of abnormal cells

Question 23

Tumors

Answer 23

Mass of cells with no apparent function (benign, malignant, metastatic)

Question 24

Benign Tumors

Answer 24

Harmless, non-cancerous, doesn’t spread

Question 25

Malignant Tumors

Answer 25

Harmful, potential to spread through body through blood, lymph, or tissues

Question 26

Metastatic Tumors

Answer 26

Has travelled and grown into other areas

Question 27

Causes of Cancer

Answer 27

Accumulation of genetic changes and mutations that disrupt instructions given to cells to stop dividing (no apoptosis) - normal cells divide a set amount of time, cancerous cells divide indefinitely

Question 28

Cancer Treatments

Answer 28

Radiation: high energy waves that kill cancer cells
Chemotherapy: anticancer drugs that kill cancer cells
Surgery: physically removes cancer cells