Theory question 104
Reproduction in Animals(a) (i) Define asexual reproduction
(ii) Name two types of asexual reproduction which occur in animals giving one example in each case
(b) In a tabular form outline four differences between sexual and asexual reproduction
(c) Make a large, labelled diagram 8 – 10 cm long of the human spermatozoon to show its structure
(d) State one function each of any three organelles found in the spermatozoon
Show the model answer
(a)(i) Asexual reproduction is the production of new individuals from one parent without the formation and fusion of gametes.
(ii) Any two with matching example: binary fission – Amoeba, Paramecium; budding – Hydra; fragmentation/regeneration – Planaria, sponges; parthenogenesis – aphids, honey bee drones; multiple fission/schizogony – Plasmodium.
(b) Asexual vs sexual: one parent vs two parents; no gametes vs gametes formed; no meiosis vs meiosis; no fertilisation vs fertilisation forms a zygote; offspring identical to parent vs offspring vary; fast, many offspring vs slower, fewer offspring.
(c) Diagram 8–10 cm, bold lines, labelled: head, acrosome, nucleus, middle piece, mitochondria (spiral), tail/flagellum; title.
(d) Acrosome – has enzymes that dissolve the ovum membrane so the sperm can enter; nucleus – carries the haploid set of chromosomes (genes); mitochondria – release energy for swimming; tail – lashes to move the sperm.
Diagram must be large, labelled and titled.